PALEOLIMNOLOGICAL SURVEY of COMBUSTION PARTICLES from LAKES and PONDS in the EASTERN ARCTIC, NUNAVUT, CANADA an Exploratory Clas

Home , Agassiz Ice Cap, Belcher Islands, Flaherty Island, Isachsen, Lake Hazen

A PALEOLIMNOLOGICAL SURVEY OF COMBUSTION PARTICLES FROM LAKES AND PONDS IN THE EASTERN ARCTIC, NUNAVUT, CANADA

An Exploratory Classification, Inventory and Interpretation at Selected Sites

NANCY COLLEEN DOUBLEDAY

A thesis submitted to the Department of Biology in conformity with the requirements for the degree of Doctor of Philosophy

Queen's University Kingston, Ontario, Canada December 1999

Copyright@ Nancy C. Doubleday, 1999 National Library Bibliothèque nationale 1*1 of Canada du Canada Acquisitions and Acquisitions et Bibf iographic Services services bibliographiques 395 Wellington Street 395. rue Wellington Ottawa ON KIA ON4 Ottawa ON K1A ON4 Canada Canada Your lYe Vorre réfhœ

Our file Notre refdretua

The author has granted a non- L'auteur a accordé une licence non exclusive licence allowing the exclusive pemettant à la National Library of Canada to Bibliothèque nationale du Canada de reproduce, Ioan, distribute or sell reproduire, prêter, distribuer ou copies of this thesis in microform, vendre des copies de cette thèse sous paper or electronic formats. la forme de microfiche/nlm, de reproduction sur papier ou sur format électronique.

The author retains ownership of the L'auteur conserve la propriété du copyright in this thesis. Neither the droit d'auteur qui protège cette thèse. thesis nor substantial extracts fiom it Ni la thèse ni des extraits substantiels may be printed or othemise de celle-ci ne doivent être imprimés reproduced without the author's ou autrement reproduits sans son pemission. autorisation. ABSTRACT

Recently international attention has been directed to investigation of anthropogenic contaminants in various biotic and abiotic components of arctic ecosystems. Combustion of coai, biomass (charcoal), petroleum and waste play an important role in industrial emissions, and are associated with most hurnan activities. A fiinctional and artificial classification of combustion particles in the arctic environrnent has been developed and applied in an exploratory paleolimnological investigation of naturd and anthropogenic combustion particulates in lake and pond sediments. Combustion particle features are descrïbed and artificial and diagnostic keys are presented. Particle photographs are included as an aid to description and identification.

The study sites selected included lakes or ponds at Alert and Cape Herschel,

EIlesmere Island, and from the west and east coasts of Hudson Bay, Nunavut, C'mada, This broad transect begins approsimately 825 km fiom the North Pole and nins almost 3000 km from Alert to the Belcher Islands. The combustion particle spectra represented in sediments varied widely: with spheroidal carbonaceous and non-carbonaceous particles contributing

>90% at the most northerly sites at Alert, and with wood charcoal comprising - 60% of the combustion particles found at Hawk Lake, Keewatin, and 20 to 45% in the Belcher Island sediments. Recent sedirnent records showed a decline in the percentage relative abundance of combustion particles of ai1 types at the top of the core at Alert. A similar change was noted at Hawk Lake, where the particle maximum dated to the 1970s. At the Belcher

IsIands however, the particle maxima occurred at the surface in two of the three sites.

The detection of a range of combustion related particles at the sites studied suggests -.. 111 that these particles may have wider application both as proxies for, and as vectors of, contaminant transport and deposition. While Merwork is required on a wider spatial scale in order to draw conclusions about causal relationsliips, we can now Say that combustion particles do appear in the sediment records in the Eastern Arctic. More importantly, these particles display spatial and temporal variability that cmbe correlated cvith otl-ier environmental trends. CO-AUTHORSHIP

In Chapter 4, the data and analysis presented for the Lower Dumbell Lake core are from an earlier paper with Marianne Douglas and John Sm01 (Doubleday et al., l996).I am the author of this mmuscnpt.

The contributions of others to this research are described in the

Acknowledgements that folIow. ACKNOWLEDGEMENTS

1would like to thank Dr. Jolm P. Sm01 for the opportunity to return to the field of paleolimnology and to experience graduate research at the leading edge in a dynamic lab group. Your enthusiasm for arctic research is an inspiration. I would like to thank Dr.

Adele A. Crowder for giving me the opportunity to pursue doctoral studies and for sharing your knowledge in the field and in the Herbarium. Thank you both for your support through good times and bad. and for your guidance for a much longer time thm any of us anticipated. 1 would like to express my sincere appreciation to Dr. Geny Morris and Dr. Bob Gilbert, for your support and encouragement. Thank you al1 for your endurance, good advice and cheerfùl responses to requests for yet another Cornmittee

Meeting. You have al1 tauzht me by your esmiples. as well as with your words. It has been a prïvilege to be associated with you.

This project would not have been possible without the support of a number of people who helped at critical times.

1 thank M. S. V. Douglas and J. P. Srno1 for providing the unpublished 2'0 Pb data used in Chapter 6. The interpretation of this data was facilitated by S. Dixit, A. Dixit,

Brian Curnming and Andrew Paterson. Also in Chapter 6, the pollen and loss-on-ignition data were analysed by K. A. Moser and the diatom data were analysed by M. S. V.

Douglas and J. P. Smol.

I am grateful in particular to Dr. L. A. Barrie, of the Atmospheric Environment

Service, Environment Canada who provided support at the outset, to Drs. J. P. Johnson,

Jr., and J. K. Torrance of the Geography Department of Carleton University who vi permitted me to borrow lab space to be nearer my family; and to Drs. Bourgeois, Koerner and Fisher, of the Glaciology Group, Geological Survey of Canada, Energy, Mines and

Resources Canada, who kindly allowed me to use their facilities for a prolonged period at an important stage and who also assisted by providing sarnples. Thank you al1 for the

Sour generosity, wonderful stories and strong coffee.

Support for the fieldwork conducted by Smol, Douglas and Doubleday at Alert kvas provided by Polar Continental Shelf. the Department of National Defence, and the

Nortliern Scientific Training Grants Program. 1 wouId also like to thank the Base

Commander and staff of CFB Alert for their generous support.

My research was supported financially by a Tri-Council Eco-Research Doctoral

Fellowship, the Lorraine Allison SchoIarship awarded by the Arctic Institute of North

America. and a Queen's Graduate Award. Following nly academic appointment to the

Department of Geoçraphy & Environmental Studies at Carleton University, 1 received support for development of a research facility, which permitted me to complete this work.

The sarnples from Pond 5, Raised Beach Pond and Dry Pond in the Belchers that I used for this study were collected by Marianne Douglas and John Smol. Samples and 2'0

Pb data from Horseshoe Pond, Cape Herschel, were provided by W. Blake, (formerly of the Geological Survey of Canada), J. P. Sm01 and M. S. V. Douglas (1994). For Hawk

Lake, 1 used published "O Pb and PAH data of L. Lockhart (Muir et al., 1996). Hawk

Lake samples were provided by Lyle Lockhart, Fresh Water Institute, Winnipeg. I thank

John Glew, Barb Zeeb and Kate Duff for collecting some combustion samples in the field. Fly ash samples were also obtained thanks to Ontario Hydro and to Dr. Malhotra vii and his lab group at CANMET. I thank Drs. R. Koerner, D. Fisher and J. Bourgeois for collecting ice and snow samples as well as sharing your knowledge.

A number of people helped with scanning electron microscopy and 1would like to thank Marianne Douglas, Ray Haythornthwaite, and Peter Jones.

1 would like to th& Marianne Douglas and John Sm01 for expert field advice, and for your support at Alert. (Without you 1am sure I would still be stuck in one of those ponds!)

Support with sample freeze-drying was kindly provided by Dr. Roger McNeeIy, of the Geological Survey of Canada, and by Paul Hamilton of the Canadian Museum of

Nature. 1would like to thank Drs, Bill Schroeder and Julia Liu, and Alexandra

Stephenson of the Atmospheric Environment Service, for their generous assistance in obtaining snow samples from Alert.

I am also indebted to those who sliared their knowledge and expertise with me. In particular 1 would like to thank Dr. Dennis Gregor, who gave me the opportunity to leam about glaciology and environmental chemistry in the field, and to his associates Dr.

Andrew Peters, Neil Jones, and the Agassiz crew. In this regard, 1 would also like to thank Dr Fred Hopper for the use of air sampling equipment, and for an expert introduction to atmospheric black carbon studies. I would also like to thank Dr. Ken

Reimer and Dr. John Poland for their interest and encouragement at the outset. 1 would like to acknowledge the contributions made to my understanding of coal by the late P.A.

Hill.

The elegant line drawings of combustion particles illustrating the diagnostic key a*. Vlll in Chapter 3 were prepared by J. R. Glew, of PEARL, with the support of J. P. Srnol.

Thank you both.

A special tl~anksto Marianne Douglas, Barb Zeeb, Tamsin Laing, Brian Cumming

and Kate Liard, Ewan Reavie, Katherine Ruhland, and Sushi1 and Amna Dixit for your

friendship and good advice, and for "showing me the ropes". A big "thank you" to al1 of

the members of P.E.A.R.L.who have been so kind and who have always cheerfully made

room for one more.

The maps showing site locations in this thesis were prepared by W. W. Munroe,

with, in the case of the site rnap for Chapter 4 (Alert), the benefit of a base map prepared

by C. Earl, Cartographer, both of the Department of Geogaphy, Carleton University.

Two of the maps in Chapter 7 showing contaminant source areas are taken from the

Arctic Monitoring and Assessrnent Program Web Site, and are used courtesy of GRID-

Arendal. W.W. Munroe assisted with SSPS analysis. Paula Carty and Erin Turner, also of

the Department of Geography, Carleton University, assisted with the bibliographie

entries. In 1995 Elizabeth Jetchick of the Department of Geography, Carleton University

assisted with sample preparation and settinç up the new lab at Carleton. Thank you,

Elizabeth, for al1 your support.

1 thank Dr. Keny Abel of the Department of History , Carleton University, for sharing soon to be published data on historical records of fires in Northern Ontario and

Quebec.

1would like to thank Larry Boyle of the Geotechnical Centre of the Department of

Geography & Environmental Studies, Carleton University, for al1 of his expert advice and ix support. I am also grateful to Ann and Mikkel Schau for their friendship. I thank Mikkel for lending me his Vickers microscope? and for his thoughtful enthusiasm and encouragement.

Families members are al1 affected when a parent returns to school. 1 wouId like to thdmy husband for his understanding and support, for sharing his skills during cornputer crises. and for the lumps of coal. 1 would like to acknowledge the late Doris and

Buster Doubleday for their encouragement and support. 1 thank rny mother for believing in me and for living to see this. Most especially 1 mnt to thank Laura who has had to share her cliildhood with my project and has done so with such good grace. TABLE OF CONTENTS

.* ABSTRACT ...... ~.. II

CO-AUTHORSHIP ...... iv

ACKNO WLEDGEMENTS ...... v

TABLE OF CONTENTS ...... x

LIST OF TABLES ...... xv

LIST OF FIGURES ...... svi

LIST OF PLATES ...... xix ... ACRONYMS ...... xsvlli ... LIST OF ABBREVIATIONS ...... xxvii~ .- GLOSSARY OF SPECIALIZED TERMS ...... xxii

SPHEROID AL BLACK LACY COMBUSTION PARTICLE ...... xxv

CHAPTER 1: INTRODUCTION ...... 1

CHAPTER 2:REVIEW OF SELECTED LITERATURE RE: THE ARCTIC CONTAMINANTS PROBLEM, COMBUSTION PARTICULATES AND THE APPLICATION OF P ALEOLIMNOLOGICAI, APPROACHES ...... ,.. 5 Arctic contaminants as an international environmental issue ...... 5 Paleoecological studies and their relevance ...... 8 Combustion ...... 1O Combustion Processes ...... 1 1 Fuels: Classification in relation to fuel type and preparation ...... 12 Coal as hel ...... 14 Coal classification ...... 15 Coal mineral content and hazardous trace elernents ...... 17 Heavy oils 19 2-10. Combustion particles and classification ...... 19 2.11. Combustion products ...... 20 2.12. Formation ofcarbon and carbonaceous particles ...... -.....-.--...... 2 1 xi Combustion particle types ...... 22 Atmospheric transport of pollutants in the Arctic ...... 24 Effect on health, ecology and economy ...... 26 Combustion particles in the environment ...... 28 Emissions ...... 30 Long-range atmospheric transport and tracers ...... 31 Combustion particle characterization ...... 33

CHAPTER 3: ATLAS OF COMBUSTION PARTICLES: A PRELIMINARY SURVEY OF COMBUSTION PARTICLES AND APPROACH TO PALEOECOLOGICAL STUDY OF THESE PARTICLES iN LAKE AND POND SEDIMENT ...... 38 3.1. Introduction ...... 38 3 .2 . Microscopy of combustion particles ...... 40 3.3. Combustion particle formation ...... 45 3.4. Materials and Methods ...... 47 3.4.1. Reference Materials ...... 47 3-42Microscopy ...... 48 3 .4.3. Particle description: quantitative and qualitative aspects ...... 50 a) Particle enurneration and size classification of environmental sarnples ...... -30 b) Qualitative factors: functional and artificial particle classification and tenninology ...... 54 3 .4.4. The identification of hctional categories for classification ...... 56 3 .5 . Particle features indicative of combustion processes ...... 65 3.6. Results of the Combustion ParticIe Study ...... 67 3 -7.1. Results Part 1. Pliotographic Atlas of Combustion Particles for Paleoecological Studies ...... 68 3-72Atlas Section 1. Combustion Particle Types in Relation to Fuels and Bumers ...... -69 3 .7.2. (a) Wood combustion particles ...... 69 3 .7.2. (b) Coal combustion particles ...... 72 3 .7.2. (c) Oil combustion particles ...... 75 3 J.2. (d) Incinerator fly ash ...... 77 3 .7.2. (e) Stationary sources in the Arctic ...... 79 3.7.2. (f) Mobile sources in the Arctic ...... 82 3.7.3. Atlas Section 2. A Survey of Cotnbustion Particles from Lake and Pond Sedirnents at SeIected Sites in the Arctic ...... 85 3.7.3. (a) Alert Sites: Self Pond and Kirk Lake ...... 85 3.7.3 . (b) Horseshoe Pond ...... , ...... 89 3.7.3. (c) Hawk Lake, Keewatin ...... 90 3.7.3 . (d) The Belcher Islands: Dry Pond, Pond 5 and Raised Beach Pond ...... ,...... -...... 92

3.8. Results Part II Development of an Artificial Classification for Combustion Particles in Sediment ...... 94

... XI11 5.2.1. Horseshoe Pond, Cape Herschel ...... -...... , ...... 156 5.2.2 .Hawk Lake, Keewatin ...... 162 5.3. Methods ...... 166 5.3.1 .Sarnpling ...... 166 5.3 .2 . Microscopical methods ...... 168 5.3 .3 . Analytical and statistical methods ...... 168 5.4. Results ...... 169 5.4.1. Descriptions of combustion particles from Horseshoe Pond, Cape Herschel ...... 169 5.4.2. Descriptions of combustion particles from Hawk Lake, Keewatin ...... 174 5.5. Discussion ...... 186 5.6. Conciusion ...... 192

CHAPTER 6: COMBUSTION PARTICLE INVENTORIES AND PALEOENVIRONMENTAL RECONSTRUCTION OF LONG-RANGE TRANSPORT INFLUENCES: A CASE STUDY FROM THE BELCHER IS LANDS. NUNAVUT ...... 194

6.1 . Introduction ...... 194 6.2. Study Site Descriptions ...... 195 6.2.1. Raised Beach Pond ...... 197 6.2.2 . Pond 5 ...... 198 6.2.3. Dry Pond ...... 199 6.3. Methods ...... 199 6.3.1. Field and laboratory rnethods ...... 199 6.3 .2.Dating ...... 209 ?? 6.3 .J . Microscopical methods ...... 202 6.3 .4 . Statistical anaIyses ...... 202 6.4. Results ...... ,., ...... 203 6.4.1. Descriptions of combustion particles from Raised Beach Pond ...... 203 (a) Spheroidal carbonaceous black particle type (SPCBK) ...... 206 (b) Charcoal: total for al1 charcoal types (chtot) ...... 206 (c) Combustion particle spectra 6-42Descriptions of combustion particles from Pond 5 (a) Spheroidal carbonaceous black particle type (SPCBK) ...... 213 (b) Charcoal: total for al1 charcoal types (chtot) ...... 213 (c) Generic combustion particle distribution ...... 216 (d) Combustion particle size distributions ...... 216 6.4.3. Descriptions of combustion particles from Dry Pond ...... - ...... 220 6.5. Discussion ...... , ...... 229

CHAPTER 7 OVERVIEW. DISCUSSION. CONCLUSIONS AND RECOMMENDATIONS FOR FUTURE WORK ...... 230 APPENDIX 1 PARTICLE CATEGORY CODES FOR INTERPRETATION OF SPREADSHEETS ...... 289

APPENDIX 2 KEY TO PARTICLE CODES FOR OPERATIONAL CATEGOMES 292

APPENDIX 3 ...... 3.1. SYNOPTIC KEY TO COMBUSTION PARTICLES ...... 293 3.2. LABORATORY METHODS FLOW CHART ...... 302 3 -3. BRITISH STANDARD GRATICULE ....-...... - .-...--..-...... -.....-...... ----...... -...... 303 3.4. COMBUSTION PARTICLE CATEGORY DESCRIPTIONS ...... 304 3 S. NON-COMBUSTION CATEGORIES OF INTEREST ...... - ....309 APPENDIX 4 ALERT SITES REPORT ON FIELD WORK AT ALERT ...... 3 1O DATA FOR ALERT SITES ...... -...... -.. .. .-.-.-.---...... 3 15 APPENDIX 5 DATA FOR HORSHOE POND AND HAWK LAKE ...... 3 19

"O Pb DATA FROM HORSESHOE POND AND THE BELCHER ISLANDS SITES ...... 325L) APPENDIX 6 DATA FOR BELCHER ISLAND SITES ...... 3283 6.2 DRY POND ...... - ...... 336?? LIST OF TABLES

TABLE 3.1 . Colour codes for combustion particle description ...... 63

TABLE 3 .z. Significance of combustion particle features in Interpretation of environmental particle records in relation to transport, deposition and possible effects ..66

TABLE 3.3. Summa-y of site location data ...... ,...... 86

TABLE 3.4. Initial descriptive categories of combustion particles used for development of the artificial classification presented in Appendix 3.1 ...... 97

TABLE 3 .S.Combus:ion particle categories defined for the purpose of making particle counts from sarnples of lake and pond sediment...... 98

TABLE 4.1 Chronology of combustion-related activities at CFB Alert, Ellesmere Island ...... , ...... 15 1

TABLE 5.1 Hawk Lake, Keewatin. Sediment slices with depth in core (cm) and median age of slice, showing levels of polycyclic aromatic hydrocarbons (PAH) and mercury ...... 167

TABLE 6.1 Raised Beach Pond Sedimentation and Combustion Chronology ...... 223

TABLE 6.2 Pond 5 Sedimentation and Combustion Chronology ...... 224 xvi LIST OF FIGURES

FIGURE 1.1. Map showing location of lakes and ponds study sites from which samples were taken for this study of combustion particles frorn selected sites in Nunavut, in the Eastern Arctic, Canada ...... 4

FIGURE 3.1. Graphical key to combustion particles ...... 1O 1

FIGURE 4.1. Map of study sites at Alert, Ellesmere Island, Nunavut ...... 122

FIGURE 4.2 Self Pond, Alert, Ellesmere Island, Nunavut. (a) The relative abundance of the combustion particle types is displayed as a percentage of al1 of the combustion particles enumerated in the Self Pond samples. (b) Self Pond, Alert, Ellesmere Island, Nunavut. The distribution of al1 combustion particle types found in the Self Pond sarn?les with depth is given as a histogram ...... 136

FIGURE 4.3 (a) shows the distribution of the Self Pond charcoal fraction of the histograrn for total particles with depth, in an exaggerated fashion. (b) presents the distribution of the spheroidal carbonaceous black particles with depth, as a percentage of the total combustion particle distribution for Self Pond. It should be noted that the scale on the x- asis has been changed by a factor of two, in order to emphasize the shape of the profile for this class of particles in the core ...... 138

FIGURE 4.4 Kirk Lake(a) displays the relative abundance of the combustion particle types as a percentage of al1 of the combustion particles enumerated in the Kirk Lake core. This histogram highlights the contributions from the spheroidal carbonaceous black (62%) and charcoal(30%) particle types. The remaining 8% of the total combustion particle load is composed of non-black spheroidal type particles and diesel-type particles which are classified as "combustion, amorphous, opaque" (cmamop). Figure 4.4 (b) presents a histogram of total combustion particle occurrence wvith depth in the Kirk Lake core. The core was sectioned continuously at 0.5 cm intervals behveen the top of the core and the bottom. The values on the y-axis correspond to the endpoint of each sarnpling interval, one subsarnple being analysed at each interval ...... 139

FIGURE 4.5. Kirk Lake, Alert, Nunavut. (a) The distribution of spheroidal carbonaceous black particles (SPCBK) is shown as a proportion of the total combustion particle occurrence, represented by the sarnples analysed from the Kirk Lake core. (b) The relative abundance of the charcoal particle distribution with depth (cm) is shown ...... 143

FIGURE 4.6. Lower Dumbell Lake, Alert, Nunavut. Histograrn showing the percentage relative abundance of soot type and charcoal particles with depth (cm) ...... 144

FIGURE 4.7 Self Pond, Alert, Ellesmere Island, Nunavut. The non-spheroidal carbonaceous black component of the particle record known to be associated with mixed xvii burning includes spheroidal non-black (SPNBK), combustion arnorphous opaque (cmamop) and combustion mixed opaque and non-opaque (cmmix) types, with a peak in relative abundance in the region of 2.5 to 3 .O cm depth...... 149

FIGURE 5.1 Site map of Horseshoe Pond, Cape Herschel, Ellesmere Island, Nunavut ...... 159

FIGURE 5.2 Horseshoe Pond, Ellesmere Island, Nunavut. Estimated aged of sediments frorn Horseshoe Pond Core 17 (BS-78-26) using U OP^ decay rates plotted with depth. (Smol & DougIas. unpublished data) ...... 161

FIGURE 5.3- Site map of Hawk Lake, Keewatin, Nunavut ...... 163

FIGURE 5. 4. (a). Horseshoe Pond, Cape Herschel, Ellesmere Island, Nunavut. Histogram showing percentage relative abundance for al1 combustion particles observed by type. (b) Histogram showing percentage relative abundance for al1 combustion particles observed by super-categorïes including "total combustion opaque" ("cmtot"), combustion generic" ("cmgen"), and total charcoal" (abbreviated as "chtot") ...... 17 1

FIGURE 5.5. Horseshoe Pond, Cape Herschel, Ellesmere Island, Nunavut. (a) Histogram showing changes in relative abundance for al1 combustion particles recorded, expressed as a percentage relative abundance with depth (cm). (b). Histogram showing changes in relative abundance with depth in the core (cm) as a prosy for changes in the temporal distribution of spheroidal carbonaceous black particles (SPCBK) with depth, expressed as a percentage relative abundance ...... 173

FIGURE 5.6. Horseshoe Pond, Cape Herschel, Ellesmere Island, Nunavut. Relative abundance of total charcoal ~4thdepth (cm), as a percentage of total combustion particles enumerated ...... 175

FIGUEE 5.7. Figure 5.7. (a), (b) and (c) Horseshoe Pond, Cape Herschel, Ellesmere Island, Nunavut. Results of the particle size class analysis for Horseshoe Pond. (a) Histogram of size class distribution of total combustion particles enumerated. Size distribution pattern of al1 the combustion particles enumerated in the Horseshoe Pond core sarnples for al1 types. (b) Relative abundance of charcoal by size class as a percentage of the total combustion particles enumerated. (c) Relative abundance of spheroidal black carbonaceous particles (SPCBK) as a percentage of the total combustion particles enumerated...... ,., ...... 176

FIGURE 5.8. Hawk Lake, Keewatin, Nunavut. Histograrns of the total combustion particle content in the sarnples analysed are presented. Figure 5.8. (a) shows the relative abundance of combustion particles by type as a percentage of the total in al1 classes, with subclasses broken dom for class 5, the opaque combustion particles. Figure 5.8. (b) xviii presents the sarne information, but for ease of cornparison with the Horseshoe Pond result in Figure 5.4. (a) shows the sum of al1 subclasses of class 5, opaque combustion particles ...... ,...... 178

FIGURE 5.9. Hawk Lake, Keewatin, Nunavut. Histogram showing the distribution of al1 combustion particles of al1 types found in the Hawk Lake sediment core samples with depth (cm), as a percentage of the total particles enumerated...... 180

FIGURE 5.10. Hawk Lake, Keewatin, Nunavut. Distribution of SPCBK type particles with depth in the core (cm), as a percentage of total of al1 combustion particles enumerated. Note that the scale of the horizontal mis has been expanded for emphasis. (b) Distribution of al1 charcoal type particles with deptli (cm), in the core as a percentage of tota1 combustion particles enumerated for a11 types. Note that the horizontal scale is reduced from that in (a) ...... 182

FIGURE 5.11. Hawk Lake, Keewatin, Nunavut. (a) Distribution of al1 classes of generic combustion particle types (crntot=cmgen+cmmop+cmRN+cmmix), with depth (cm) as a percentage of total combustion partides enumerated. (b) Distribution of the sum of al1 classes of opaque combustion particle types (cmoptot=cmtot-cmmix), with depth as a percentage of total combustion particles enumerated...... 184

FIGURE 5.12. (a), (b) and (c). Hawk Lake, Keewatin, Nunavut. Results of the particle size class analysis. Histogram of size class distribution of total combustion particles enumerated. (a) Size distribution pattern of al1 the combustion particles enumerated in the Hawk Lake core samples for al1 types. (b) Relative abundance of charcoa1 by size class distribution of the total combustion particles enumerated. (c) Relative abundance of spheroidal black carbonaceous particles (SPCBK) as a percentage of the totaI combustion particles enumerated ...... 185

FIGURE 6.1. Site location map of Raised Beach Pond, Pond 5 and Dry Pond, Belcher Islands, Hudson Bay, Nunavut...... -196

FIGURE 6.2. Raised Beach Pond, Belcher Islands, Hudson Bay. Histogram of the total distribution of combustion particles in al1 samples from Raised Beach Pond by particle type ...... 205

FIGURE 6.3. Raised Beach Pond, Belcher Islands, Hudson Bay. Total distribution of combustion particles of al1 types and OP^ dates ...... 207

FiGURE 6.4 Raised Beach Pond, Belcher Islands, Hudson Bay. Spheroidal carbonaceous black particle (SPCBK) type and P OP^ dates ...... 208

FIGURE 6.5. Raised Beach Pond, Belcher Islands, Hudson Bay, Nunavut. Histogram showing total distribution of charcoal particles of a11 types for al1 sarnples analyzed .... 210 FIGURE 6.6. Pond 5, Belcher Islands, Hudson Bay, Nunavut. Histogram showing the relative abundance of combustion particles by type, as a percentage of the total combustion particles enurnerated in the Pond 5 sarnples ...... -214

FIGURE 6.7. Pond 5, Belcher Islands, Hudson Bay, Nunavut. Histogram of the distribution of the total combustion particle load of al1 types with depth at Pond 5, as well as inferred OP^ dates ...... 2 15

FIGURE 6.8. Pond 5, Belcher Islands, Hudson Bay. Nunavut. Histogram of the distribution of spheroidal carbonaceous black type combustion particles to the total combustion particle load with depth at Pond 5 ...... 217

FIGURE 6.9. Pond 5, Belcher Islands, Hudson Bay, Nunavut. Histogram of the relative abundance of total charcoal with depth ...... 2 18

FIGURE 6.10. Pond 5, Belcher Islands, Hudson Bay, Nunavut. (a), (b) and (c) present the results of the size class distribution for al1 combustion particles enumerated in the Pond 5 sarnples; for total charcoal type particles; and for spheroidal carbonaceous particles (SPCBK type), respectively ...... 219

FIGURE 7.1 Schematic map of central industrial areas and dominating air currents as identified by the Arctic Monitoring And Assessrnent Program ...... 23313

FIGURE 7.2 Known pathways of pollutant transport in the northern hemisphere, as identified by the Arctic Monitoring And Assessment Program...... 234

FIGURE 7.3 Major ocean curent influences linking the North Atlantic and the Eastern Arctic. The long arrow indicates the Gulf Stream ...... 235

FIGURE 7.4 Relative abundance of the total particle record of super groups A, B, C, D and E at al1 of the sites, expressed as a percentage of al1 of the sample sets analysed. Values were standardized to take into account variations in the numbers of samples. 238

FIGURE 7.5 Relative abundance of the particle record of super groups A, BIC, D and E in the top layer at al1 of the sites, expressed as a percentage of al1 of the sarnples analysed...... 23 9

FIGURE 7.6 Map showing the location of treeline and the 10" C July isotherm ...... 24 1

FIGURE 7.7 Map showing the location of known sources of emission of airbome particdates in relation to the transect fkom Alert to the Belcher Islands. Dominant air currents are shown and the Gulf Stream is indicated ...... 244 XX FIGURE 7.8 Particle size distributions of spheroidal black particles by particle diameter size class shown as percentage relative abundance with depth in core for a) Horseshoe Pond, Cape Herschel; b) Hawk Lake, Keewatin; and c) Pond 5, Belcher Islands ...... 345

FIGURE 7.9.. Horseshoe Pond, Cape Herschel, Ellesmere Island. ReIative abundance of particles by particle type, particle size (maximum diameter), and depth ...... 246 xxi

LIST OF PLATES ...... Page PLATE 1, FIGURES 1 TO 16 WOOD COMBUSTION PARTICLES ...... 71

PLATE 2, FIGURES 1 TO 22 COAL COMBUSTION FLY ASHES ...... 74

PLATE 3, FIGURES 1 TO 13 01L COMBUSTION PARTICLES ...... 76

PLATE 4 FIGURES 1 TO 12. INCINERATOR FLY ASH COMBUSTION PARTICLES ...... -78

PLATE 5 FIGURES 1 TO 25. STATIONARY SOURCES OF COMBUSTION PARTICLES ...... 8 1

PLATE 6 FIGURES 1 TO 15. MOBILE COMBUSTION PARTICLES ...... 84

PLATE 7 ENVIRONMENTAL COM8USTION PARTICLES 1 FIGURES 1 TO 18. ..A7

PLATE 8 ENVIRONMENTAL COMBUSTION PARTICLES II FIGURES 1 TO 25. ..88

PLATE 9 ENVIRONMENTAL COMBUSTION PARTICLES III FIGURES 1 TO 23 ..9 1

PLATE 10 ENVIRONMENTAL COMBUSTION PARTICLES IV FIGURES 1 TO 25 ...... -93

PLATE Il ENVIRONMENTAL COMBUSTION PARTICLES V FIGURES 1 TO 25 ...... 105 xxii

ACRONYMS

AMAP Arctic Monitoring and Assessrnent Programme

P.E.A.R.L. PaleoecologicaI Assessment Research Laboratory,

Department of Biology, Queen's University

LIST OF ABBREVIATIONS

1. GENERAL

AsP crossed polars

LM light microscopy

PO polars removed

PP plane polarized Iight,

R for red. an aspect of hue in the Munsell CoIour Classification

SEM scanning electron microscopy

YR for yellow-red, an aspect of hue in the Munsell Colour CIassification

Y for yellow, an aspect of hue in the Munsell CoIour Classification

2. PARTICLE TYPES

ch or CH charcoal charn amorphous chbloc blocky chang anguIar xxi ii chtot total charcoal of a11 types chlath lath chnid rounded cm combustion, generic cmlacy combustion - lacy cmammix combustion arnorplious mix opaquehon-opaque cmamop combustion opaque arnorphous cmamnop combustion amorphous non-opaque cmamor combustion - arnorphous c nmmrn combustion - rounded amorphous cmanop combustion opaque, angular cmop combustion opaque cmoprn combustion - rounàed

Csph opaque spheroidal comples (cenosphere)

NBKSP non-opaque spheroidal simple particle, non-black; maybe further descri bed as:

TI Translucent coloured

YI Yellow

Br Brown

RD Red

W White

NBKSPH non-opaque spheroidal complex combustion particle xxiv hïSPBK non-spheroidal combustion partide bIack

NSPBK(l2) non-spheroidal combustion particle black to dark red "diesel-type"

Psph Pleurosphere

SCP spheroidal carbon particle

SPBK spheroidal combustion particle, black

SPBK(A.xP) spheroidal combustion particle? black to red with crossed polars (AxP)

GLOSSARY OF SPECIALIZED TERMS aciform needle-like aciculate covered with aciculae or needles aciniform grape-like (of carbonaceous spheroids or masses) charring blackening and fragmentation along structural planes sootino- accretion of black carbonaceous films over a surface xxv SPNEROIDAL BLACK LACY COMBUSTION PARTICEE

Note: scale bar measures 50 Fm. CHAPTER 1

INTRODUCTION

This project began as an attempt to apply rnethods developed by Rose (1990) and

Renberg & Wik (1985a) to separate black carbon particles from lake and pond sediments in the High Arctic in order to investigate possible relationships with transport and possible sources, and ultirnately with patterns of anthropogenic contaminants and ecosystem change. It was very much a case of explonng the unknown as, to my knowledge when 1 began this work, no similar study had previously been attempted in the

Canadian Arctic and there was no certainty as to the outcome. However 1was encouraged by reports in the literature of sorne of the atmospheric studies which had documented the presence of large (>2 pm) combustion particles apparently undergoing long-range transport in the Arctic (Bailey et al., 1984, Sheridan et al., 1990), as well as reports of deposition in the Arctic of combustion particles from distant sources (Welch et al., 199 I), and by the interest of individual scientists, such as Drs. J. P. Smol, A. A. Crowder, L. A.

Barrie and D. J. Gregor, who encouraged and supported this work from the beginning.

This study is very much a preliminary exploration of the application of paleolimnoIogical methods to the investigation of combustion particle occurrence in selected lake and pond sediments from the Eastern Arctic.

While an enorrnous body of research exists with respect to &el-specific combustion particle characterization for engineering purposes, and there is a growing literature that documents combustion particle occurrence in various environrnents, atmospheric studies of particle distribution and origin, paleoecological study of the spatial 2 and temporal distribution of combustion particles and ecological studies of effects of particles in the environment, there is much less information which is specific to studies of combustion particles in the Arctic. FortunateIy a number of valuable review papers and conference proceedings are now available which provide access to the literature not specific to the Arctic, and the interested reader will be directed to these works as appropriate. It is only possible to highlight a selection of these excellent and relevant papers of general application to combustion studies in the literature review.

When 1 started this project, 1 assembled a wide range of reference materiais, including samples of standards and known combustion particles, such as fly ash from coal and oil fired power plants, but also from the types of sources frequently found in the

Arctic: diesel-powered generators, heavy equipment, aircrafi, and cornmunity sources. It was the investigation of these various sources and the combustion particles associated with them which 1 found challenging, and that diverted me from my original focus on black carbon particles to a consideration of the wider range of combustion particles which occur.

The present work draws upon combustion particle characterization studies and appIies the artificial, functional classification which I developed, based on those studies, to a preliminary investigation of the occurrence of combustion particles in the sediments of lakes and ponds at various sites in the Eastern Arctic. The information gathered serves both as an inventory and as the basis for chronological interpretation using paleolirnnological methods, to reconstruct combustion histories and atmospheric contributions of combustion particles. In the case studies that follow, I relate these patterns of occurrence or combustion histories, to other forces, phenomena or events, where possible.

The thesis moves fiom the general review of literature that follows this introduction, into a detailed consideration of the problem of combustion particte identification and characterization in Chapter 3. In Chapters 4, 5 and 6, I present combustion histories reconstructed fiom lake and pond sediments for selected sites (see

Figure 1.1) from Ellesmere Island, Keewatin and the Belcher Islands in Hudson Bay. In

Chapter 7,1 briefly examine these findings in the context of a regional view of meteorological phenomena, patterns of occurrence of contarninants and sources of combustion, leading to the conclusions and recommendations for fùture work.

Since the primary focus of the research is on the industrial period and the occurrence of combustion particles in the high arctic environment. the timespan on which this study focuses is approximately the last 200 years.

In addition to my researcli on combustion particles in sediments, which is the primary focus of this thesis, 1 also studied combustion particles in surficial snow fiom terrestrial sites, from the permanent polar ice pack and in ice cores from placier ice. This work is continuing and is referred to briefly in the chapters that fotlow. FIGURE 1.1. Map showing location of lakes and ponds from which sarnpks were taken for this study of combustion particles from seIected sites in Nunavut, in the Eastern Arctic, Canada.

CHAPTER 2

A REVIEW OF SELECTEI) LITERATURE IRE: THE ARCTIC

CONTAMINANTS PROBLEM, COMBUSTION PARTICULATES AND THE

APPLICATION OF PALEOLIMNOLOGICAL APPROACHES

2.1. Arctic contaminants as an international environmental issue

In the Iast ten years the issue of arctic contaminants has achieved national and

international significance. as the risks to arctic peoples and ecosystems are more fully

understood (Doubleday. 1997). These developments have largely been the result of the detection of a wide range of anthropogenic toxic contaminants in the arctic ecosystem, including organochlorines (Gregor & Gummer, 1989; Gregor et ai., 1999, heavy metals

(Hermanson, 1991). polycyclic arornatic hydrocarbons (Wong, 1985; Greenaway et al.,

1991 ; Lockhart et al.. 1993) and acidic precipitation (Koerner & Fisher, 1982; McNeely &

Gummer. 1985). Given that combustion is the bais of industry and of energy production. providing on the order of 90% of al1 energy utilised, it is not unreasonable to anticipate an association between combustion products and contarninants, as "combustion is the main source of pollution in the naniral environment" (Chomiak, 1990). Moreover, combustion products, both particdate and gaseous, are a class of pollutants (Vandegrift et al., 1971).

Fyfe (1 993) makes the point that with a growing global population, increasing consumption of fossil hels and concomitant increases in wastes emitted is irnplicit: the only question is whether the rate of consumption will correspond to that of the developed world- in which case "the hture would be disastrous". Given the potential of the Arctic for amplification of 6 environrnentai change due to its unique geophysical conditions, as well as the vulnerability

of its peoples and biota to the effects of contarninants as a result of prevailing ecological

and social characteristics, cornpelling arguments exist for increased research effort in the

Arctic (Sparck & Friday, in Stonehouse, 1988; Walsh, 199 i ;Kellogg, 1995).

Previously, much of what we knew about the occurrence of contarninants in the

Arctic was learned through sectoral studies of atmospheric chemistry and the analysis of

diets of indigenous peoples. Recently the Arctic Monitoring and Assessment Programme

(AM)issued the "AMAP Assessment Report: Arctic Pollution Issues" (AMAP, 1 998),

which reports the results of a multinational, multidisciplinary research and policy initiative,

under the auspices of the international Arctic Environmental Protection Strategy. This

Report is a comprehensive analysis of current knowledge about the Arctic and the sources, padiways, sinks. ecological and cultural effects of contarninants in the circumpolar region (

AMAP, 1998).

The character of the contarninants found in the Arctic strongly suggests that the majority of these substances must be originating in industrialised or agricultural regions, and then undergoing long-range transport (Stonehouse, 1988). For exampie. few local sources of organochlorine contarninants are found in the Arctic; however organochlorines such as hexachlorocyclohexane (HCH), hexachlorobenzene (HCB) and toxaphene are widely distributed in the arctic environment and in arctic biota (Jensen, 1990). Toxaphene

Ilas been found in many studies, including in air samples taken at the Canadian Ice Island where the average air concentration values ranged fiom 36 to 44 &m3 (Bidleman et al.,

1989; Patton et al., 1989) and in burbot (Lota Iota) livers in the Northwest Temtories at 7 levels of 0.9 to 1.1 ~_ig/g,lipid weight bais (Muir et al., 1990). Toxaphene has been used in

conon production, but has been banned in North Arnerica, except for some licensed uses.

One application of toxaphene is known in the arctic ecosystem (as a piscicide in a lake in

the Yukon); othenvise its presence as one of a suite of contarninants has been accepted as

evidence of the importance of long-range transport as a source (Jensen, 1990). While in

general a north-south gradient has been observed for less volatile compounds, levels of

toxaphene and HCB in the kctic are ofien as high as in source areas, and tend to be as high as areas otherwise considered to be more contarninated, such as the Baltic Sea and the Great

Lakes (Shearer, pers. commun.). The significance of contaminant levels in the Arctic does not rest solely on relative values for contaminant concentrations however; the Arctic is considered to be more vuinerable because of its lower species diversity, shorter foodchains, and dominance of the ctosed lipid chain in energy transfers within the arctic ecosystem.

Research has been done on models for atrnospheric and oceanic circulation related to contaminants (see for exarnple Ottar, 198 1; Barrie & Barrie, 1990; Barrie et al., 1992): on tracing of contaminant origins (Bidleman et al., 1989; Nriagu et al., 199 l), and on ecosystem studies (Hargrave et al., 1989; Wania &c Mackay, 1993) which suggest that the

Arctic may act as a si& for airborne contarninants, and tliat there are relatively few pathways by which contaminants cm then leave the Arctic (Gregor et al., 199 1; Shaw,

1993). Given the tendency of many of these substances to bioaccumulate, and in some cases to interfere with biological activity in organisms, as well as the unique characteristics of the arctic ecosystem itself (Barrie et al., 1992), there is great interest in understanding sources. 8 sinks and pathways of arctic contaminants, as well as long-term ecosystem effects (Arctic

Environmental Protection Strategy, 199 1).

In addition to concerns about ecological consequences of contarninants, there is a long-standing awareness of the potential for atmospheric combustion product loadings, and subsequent deposition, both gaseous and particulate, to affect climatic change (see for esample, Rosen & Hansen, 1984; Haywood & Shins, 1995; Pemer et al., 1992), which argues for increased attention to the distribution of such products in the environment.

2.2. Paleoecological studies and their relevance

Paleoecological studies can make a unique contribution to the investigation of combustion-related aspects of the arctic contarninants issue for many of the same reasons that they are valued in other scientific contests (Smol, 1992). Paleolimnological studies in particular provide baseline data on a chronological basis which is invaluable for monitoring and assessing environmental change, and which would otherwîse be unobtainable, given the limitations on the recording of systematic observations in the Arctic. The paIeoecological record cm also provide information about past conditions over a timespan much longer than that possible wîth other biobgical or toxicoIogical studies (Smol, 1992). Paleoecological techniques have been applied to studies of poilen, charcod, diatoms and macrofossils found in arctic lake sediments and in ice cores. Paleoecological approaches to studies of pollutants in ice and snow in the Arctic have been successfül in identifiing early occurrences of anthropogenic contaminants such as lead (Alderton, 1985; Rosman et al., 1997). Elsewhere, lake sediments have proven to be reliable archives, recording air pollution and Lake response

(Norton, 1986; Charles & Whitehead, 1986). 9 Paleolimnological research is usually dependent upon the presence of quantifiable

durable indicators. Traditionally, remains of organisms have been used by paleolimnologists

as a means of reconstmcting pre-historic conditions. For example, diatorn valves (Smol et

al., 199 1)' chrysophyte cysts (Duff et al., 1991 ), and pollen grains (Fredskild, 1973) are

fiequently preserved in sediments and available for analysis of a range of environmental

conditions (Charles & Smol, 1994). Even more subtle remains, such as fossil pigment from

living organisms found in sediments have proven useful (Leavitt, 1993). The occurrence

and preservation of charcoal in sediments studied for pollen analysis has been noted since

the begiming of such studies (Iversen, 1934, cited in Paterson et al., 1987). Attempts to observe, quanti@ and interpret charcoal occurrence in relation to vegetation, human settlement, natural fire regimes, and climate followed (for example: Swain, 1973; Cwynar,

1978; Terasmae & Weeks. 1979; Cope & Chaloner, 198 1; Tolonen, 1985; Winkler, 1985;

1994).

Paleolimnological analysis of microfossil remains has been enhanced by sedimentological and geocliemical analysis of sediment cores as well. In the case of contaminant studies in sediments, while physical and chernical measures are often the first choice of researchers, transfer fùnctions based on microfossils have also proven useful for development of proxies for evaluation of environmental pollutants such as acid rain (Smol,

1986; Charles et al., 1989; Disit et al., 1992).

Analogous to the use of microfossils for interpretation of environmental change, interest has developed in using the artifacts of anthropogenic industrial activities as quantifiable indicators for paleolimnoiogical studies. Hemng (1 977), Grifin & Goldberg 10 (1979)~Goldberg (1985), Renberg (1984), Renberg & Wik (1985a_ b), Rose (1990) and

others have al1 made persuasive cases for study of combustion products, particularly

sphencal black carbon particles, in sediments, as having utility in the investigation of

industrial and environmental history.

2.3. Combustion

Fire has functioned as a force in nature throughout geological time and as a tool in the hands of humans for at least 600 ky (Weinberg, 1976), and possibly longer. As a result. combustion particles can be found in virtually every environment on earth, giving evidence of their origin and stimulating a variety of scientific investigations, including climatic reconstruction. assessment of ecologica1 adaptation, tracing of nutrient cycling and systemic studies of emissions. In industrial society, combustion-generated energy is at the heaft of most material production processes. is the source of over 90% of the energy produced? and. as such, is the most important contributor of pollutants emitted to the environment (Chomiak? 1990).

Chomiak (1 990) describes combustion as chemical changes OCCU~~~when fùels and oxidizers corne into contact. These "rapid osidation reactions" are usually understood to involve a series of chemical reactions "accompanied by a release of heat and an emission of light". The complexity of the chemical reactions involved is illustrated by the fact that in his outline of combustion research, Chomiak States that the best known system of combustion reactions is that for CO-H202,and that it "involves 12 active chemical species... and more than 60 reactions." Given the relatively simple molecules involved in the combustion reaction used in this example, and the complexity of the resulting reaction II products, one can appreciate the uncertainties which exist in defining such series when complex fuels composed of macromolecules such as wood or coal are involved.

2.4. Combustion Processes

Although combustion processes share obvious similatities, in tems of the oxidation and reduction of füels on esposure to flame or other igniters, there are also dissimilarities, resulting in part from the range of conditions, fuels and burner designs involved. In ternis of the fundamental processes, there are sorne basic similarities: as the series of reactions proceeds, there is a proMeration of creation of activation centres which are single atoms or small molecules which are stable, but electrically charged. As the reaction series proceeds, each activation centre generates multipIe new ones, producing a

"branched-chain reaction" (Chomiak, 1990). In osidation at high temperatures, if a run- away branched chain reaction can generate free radicals faster than they are removed, ignition can result (Heicklen, 1976). Reduction reactions can lead to pyrosynthesis of benzene and related precursors of polycyclic aromatic hydrocarbon synthesis at temperatures of 400 to 500°C and subsequentIy to production of "soot" when fuel-rich mixtures are heated beyond cracking, at 600°C to above 1000°C (HeickIen, 1976). Lewis

& Singer (1988) characterize the mixture forrned in the first stage in pyroIysis as "pitch" which is hedat about 350-500°C, followed by formation of coke, described as an

"infusible polymeric hydrocarbon" near 500°C. Continuation of heating leads to formation of carbon polymers and finally to graphite at about 3000°C (Lewis & Singer,

1988). Graphite consists of pure crystalline carbon in hexagonal plates that are stacked upon each other. 12 For hydrocarbons, the molecuIar structure, particularly the ratio of hydrogen to

carbon, and the bond energies of the associated groups, determine the characteristic

combustion process and products for the hydrocarbon concerned. For example, fuels with

a low WC ratio, such as coal(0.75), are characterized by heavy emissions of soot when

burned, as contrasted with petroleum which has a much higher H/C ratio (2.0) (Chorniak,

1990).

2.5. Fuels: Classification in relation to fuel type and preparation

Hydrocarbon fuels may be gaseous, as in the case of natural gas, liquid for

esample petroleum, or solid such as coal. In one sense, a11 fuels are transforrned to

gaseous conditions in the combustion process, as volatiles in the vapor phase lead the

reaction process at the flarne edge. Arnong hydrocarbons, the spectrum of states from

vapor to solid reflects an increase in molecular weight, and a corresponding decrease in

volatility (Stach et al., 1975).

The categorization of fuels by phase may convey an overly simpIistic view of the

nature of hydrocarbons, by implying a false impression of homogeneity within each

phase. While highly refined gaseous or liquid fuels rnay have a relatively narrow range of

performance values, freqriently these parameters are guaranteed by the addition of vanous

conditioners, catalysts, and other substances, which serve to increase the heterogeneity of the fuel and of the resultant combustion products. Heavier fuels, such as diesel, or

feedstocks, such as Bunker-C crude oil, are intrinsically more variable in composition.

Petroleum is fractionated into various components and grades of fuel through a process of 13 hydrocarbon distillation or cracking, producing a range of products used in industry as feedstocks and as fiels for combustion in a wide range of bumers and engines.

Solid fiels, such as wood or coal, are also inherently highly heterogeneous.

Variability within these groups is significant, and the differences are reflected in fûel composition, structure, specific heat, and hardness. Pre-treatment, whether the washing of coal to remove particle-forming minerais, or the chernical or mechanical digestion of wood, will also have an impact on the emissions resulting from its use as fuel (Lessing,

1930; Schultz et al., 1975; McCrone & Delly, 1973).

Wood is divided into two primary categories with reference to the type of tree froin which it cornes: hardwoods are identified with deciduous trees termed

'-angiosperms" and sofiwoods', with coniferous trees or "gyrnnosperrns". In addition to seed habit, conifers and deciduous trees are distinguished by the presence of vessels that are found in deciduous trees. These divisions are not strict with respect to features of interest to combustion studies; however, generally speaking, conifers contain a higher proportion of volatiles, particularly resin (Stach et al., 1975), burn more quickly and produce more smoke and related particulates than hardwoods. Hardwoods are considered to have the greater heating value, in tems of calories produced. Hardwoods contain very little resin, but are rich in waxes (Stach et al., 1975). From the point of view of particle formation, the most important molecules in wood are lignin and cellulose, the macromolecules that form ceIl walls and other structures (Bailey, 1938; Bailey & Kerr,

' However the terrns "hardwood" and "softwood" are not related to the hardness of the wood, according to Hoadley (1990). 14 1935; Bailey & Vestal, 1937). Cellulose is a polymer built from units of the glucosan monomer (Chomiak, 1990). Lignin is a heterogeneous, fibrous material with exceedingly comples structure, built from alcohol derivatives of phenols, and possessing an aromatic ring structure (Bidwell, 1974). Its exact structure is difficuIt to define due to the degradation which occurs during extraction (Bidwell, 1974).

A nurnber of trace elements are associated with wood (Philpot, 1968), as a result of selective uptake of nutrients, such as molybdenum, copper, zinc, manganese, iron, boron, magnesium, potassium and calcium; and non-essential elements, such as silica. sodium, aluminum, barium, strontium, titanium, lead, rubidium, silve- zirconium, lithium, nickel, chromium, cobalt, tin and vanadium, as shown by studies of biogeochemical cycling in woodlands (Fortescue & Marten, in Reichle, 1970). Upon complete combustion. these elements are released, in the form of gases or solids. Many minerals are concentrated in the Sap and contribute to the anisotropy of wood fragments subjected to incomplete combustion (see Chapter 3: Plate 1).

2.6. Coal as fuel

Coal is perhaps the best example of a complex fuel substance and of a correspondingly complex classification system. Coals are divided into categoxies, or ranks, which correspond to their degree of coalification, or progression along the metarnorphic continuum from peat to lignite, subbituminous, bituminous, anthracite and meta-anthracite coal (Stach et al., 1975). Coalification is thought to result fiom the effects of time and temperature. Pressure is of importance in the transition from peat to lignite, 15 where some 50% of the moisture and porosity of the peat may be driven off by pressure.

However for the transformation of lignite through higher ranks, time and moderate temperature are the main influences. A temperature of 100-1 50°C is hot enough for formation of bituminous coals, according to Blatt (1982). As the coal rank increases, the percentage of volatile matter decreases and the percentage of fixed carbon increases.

There is also a change in the orientation of the macromolecules in the coal towards an increasingly ordered state, In the course of this transition, aliphatic components are

"gradually removed while the aromatic components coalesce into Iarger clusters" (Stach et al., 1975). At the same time, there is an increasing ordering of hurnic compounds parallel to the bedding which is visible microscopicalIy as an increase in anisotropy, until the anthracite or subanthracite stage is reached, at which point the coal becomes isotropie.

AIso. corresponding to increasing rd,vitrinite reflectance increases as metamorphism proceeds.

2.7. Coal classification

Depending upon the classification used, commercially available coals are divided into sofi and hard coals, or into lignite, bituminous and anthracite, GeneraIly, soft coaIs correspond to the categories of lignites and bituminous coals, while hard coaIs correspond to anthracite. Very hard bituminous coais may also be included in the "hard" coal category.

Although not central to the purpose of this review, the approach taken to further classifi coal by Marie Stopes in 19 19 is of interest from the point of view of providing an example of an attempt to deal systematically with classification of a heterogeneous 16 material (Van Krevelen, 1961). This example may be relevant to the problem of

classification of heterogeneous combustion products, at least in illustrating the nature of

the problem. Stopes classified macroscopic biturninous coal according to a systern of rock

types, termed vitrain, clarain, durain and fusain. In 1957, Stopes added two more

intermediate "rock?' types to her classification of macroscopic coal. Following the

introduction of the reflected light technique using blocks of polished coal for purposes of

microscopical study by Stach et al. in 1925, the classification of coal proceeded, using

microscopical featrires. In 1935, Stopes proposed the application of the terrn maceral to

label microscopically observable constitutents of coal.

While macerals in coal can be considered to be the equivalent of minerals in

rocks, minerals are uniform in substance, crystaIline in nature and chemicaIIy distinct,

whereas macerals tliemselves are heterogeneous within each group' varying widely in

physical properties and chernical composition. Characteristics used to distinguish

macerals include reflectance, colour, shape, and relief or potishing hardness, al1 of which

are related to morphology (Stach et al., 1975).

According to Stach et al. (2975), there are three prirnq rnaceral groups: vitrinite,

exinite and inertinite. These groups are further subdivided into an open-ended,

overlapping and incomplete array of macerals, subniacerals and maceral varieties.

Macerals are not restricted to single rock-types. Coal petrologists identi@ macerals

according to differences in morphology and structure, by optical rnicroscopy using

reflected light on specially prepared polished coal "buttons". The maceral categories observed microscopical1y are related to the types of biological materials from which the 17 coal was fonned, as well as to some conditions of formation such as salt-water inundation. For example, vitrinite is formed from woody and cortical tissues, and occurs as two main types: the first in which cellular structure can still be seen, called telinite; and the second, coIlinite7which is structureless (Blatt, 1982). Esinite includes macerals formed from spore exines termed "sporinite", cuticles ("cutinite"), plant resins and waxes

("resinite"), algal remains ("alginite"), and stnictureless material "too small in size" to be included in one of the previous groups ("liptodetrinite") (afier Blatt, 1982 p. 460).

Inertinite macerals are füngal materials (termed "sclerotinite"), oxidized or carbonized wood or bark (fossil charcoal, "Fusinite*' or "semi-fusinite"), or other plant materials of uncertain origin, which is stnictureless (termed "micrinite", if particles are 4 0 mm, or

"macrinite" if >l O mm (Blatt, 1982).

In the exarnple of coal classification summarized above, not only are coal types themselves each heterogeneous. the types can also intergrade with one another; and the classification is circumscribed by the ability to determine constituent parts. Where origin and composition can not be used to define the type, a residual class is created, defined on the bais of physical characteristics, in this case, size.

2.8. Coal mineral content and hazardous trace elernents

While coal types are based on the coal particle (maceral) classes like those discussed above, coal grades are defined by chernical anaiysis related to Ievels of impurities, such as ash-forming rninerals, with lower grades of coal having larger amounts of impurities (Blatt, 1982 p. 453). Minerals in coal present a special case: Stach et al. (1975) identified 45 minerals that rnay be present in coal. In fly ash, Stach et al. 18 (1975) identified silicates, hematite, rnagnetite, maghemite, and carbon as the major mineral components. Davidson & Clarke (1 996) provide the following list of rninerals in coal which are associated with potentially toxic trace elements: pyrite, marcasite, galena, sphalerite, other sulphides, iron oxides and hydroxides, chromite and spinels, other oxides and hydrous oxides, clay minerals, feldspars, other silicates, calcite, dolomite, ankente and siderite, other carbonates, phosphates and volcanic glass phases. Trace elements which are toxic and have the potential to become airborne on combustion are associated with these rninerals, including beryliium, chromium, manganese, cobalt, nickel, arsenic* selenium, cadmium, antimony, rnercury and lead, to narne the eleven which have been designated hazardous by the United States CIean Air Act Amendments of 1990. There are many other trace elements associated with coal, which are not considered to be toxic.

In general, discrete mineral grains are studied independent of the coal macerals, b~itminerogenic inclusions within macerals are treated as part of the maceral. While it is the mineral content primarily, which fouls combustion chambers and creates fly ash spheres, Stach et al. (1 975) are strongly of the view that the combustion techniques rather than the characteristics of the coal determine the nature of the slag produced within a coal grade. However, it would seem reasonable to expect those higher grades of coal with less minera1 content would produce less residual slag, ash and emissions, under equivalent burning conditions, and therefore coal quality is of equal concern.

As illustrated by the discussion above, coal classification and its related nomenclature is cornplex. As Blatt (1982, p. 462) describes the situation: "Clearly similar sounding terms do not have identical meanings and some tenns used by the coal 19 petrologists have partially overlapping meanings, fitfalls in the usage of coal terminology

in petrologic studies are abundant, and great care is required to avoid falling into a

trackless morass."

Given the heterogeneous nature of the biomass which forrns coals, it is not

surprising that when one moves beyond the recognition of coaI as a class of organic rock,

classification, whether based on macroscopic or microscopic features, is problematic.

When coal becomes he1 for combustion, it is reasonabie to expect the products to be

variable. This is helpful from the point of view of understanding the diversity apparent in

single file1 combustion sarnples (see Chapter 3, Plate 2, Figures 1, 2, 5 & 6).

2.9. Heavy oils

Heavy oils are a1so capable of forrning a variety of combustion particles, as

iIIustrated in Chapter 3, Plate 2. The presence of catalysts may also contribute to particle

diversity (McCrone & Delly, 1973). Studies of trace metals and carcinogens in diesel and

heavy oil suggest that various toxic elements and compounds are associated with oil as

they are with coal (Bacci et al., 1983).

2.10. Combustion particles and classification

The problem of combustion particle study and classification, therefore, is two-fold

and consists of the determination of the origin of particles as being derived by combustion, and selecting criteria which can then be used to establish meaningfiil and usefùl categories for documenting the occurrence of types of particles in order to support subsequent environmental analyses. Both steps must take into consideration the wide range of types of fuels, burners and products, and the resultant diversity of particle types. 20 Fuels, except for biomass which feeds wildfire, are usually pre-treated: petroleum products are separated by thermal and chernical processes; coals are crushed and may be washed; and industrial wood waste may have been mechanically or chemically treated pnor to being scrapped and burned. Additives to support combustion, such as catalysts in the case of petroleum based füels (McCrone & Delly, 1973), oil in the case of coal

(American Concrete Institute (ACI), 1996), or other arnendments designed to alter ernission characteristics, may also be present when the fuel is burned, and contribute to the diversity of combustion products which result.

2.1 1. Combustion products

Fuel type, treatment. burner type, burning conditions (particularly, temperature and oxygen levels), trace constituents of the fuel, additives and related industrial processes, al1 interact to generate a wide range of particles (McCrone & Delly, 1973).

Given the complexity of combustion as a process, the range of conditions created by these external variables, and the large number of combustion-driven industrial processes that esist. it is not surprising that combustion particle diversity is high.

In the process of forrning pitches with heating, hydrocarbons assume some of the properties of crystals and some of glasses in varioiis transition States, forming liquid crystals. With heating, heavier molecular weight hydrocarbons aggregate and settle out of the lower molecular weight, isotropie phase as "anisotropic spherules". With continued heating, the entire pitch enters mesophase and eventually anisotropic coke is formed

(Lewis & Singer, 1988). Lewis and Singer define the difference between pitch and coke 21 in terrns of fusibility: pitches are fusible, forming plastic rnelts (Van Krevelen, 1961);

white cokes do not (Lewis & Singer, 1988).

2-12. Formation of carbon and carbonaceous particles

A number of mechanisms have been proposed for the formation of elemental

carbon. According to the Science Research Council(1976), "graphite formation demands

the progression from acetylene to polynuclear aromatic hydrocarbons (PAHs) which

polymerize to graphite." Graphite is a highly ordered and symmetrical forrn of carbon in

which regular hexagonal carbon plates forrn stacks. Graphite is one of the two crystalline

forms of carbon, diamond being the other.

The progression from simple to complex carbon molecules to highly ordered

graphite in the process of combustion is anaIogoiis to the increasing order observed in the 4- process of coalification: increasing coal rank, as measured by iiicreasing reflectance, indicates increasingly ordered arrangements of carbon compounds.

To further complicate matters, there are suggestions that the ultimate end products of interna1 combustion engines burning diesel and other petroleum products may be volatile materials which most closely resemble bituminous coals in composition and structure (Ebert et al., 1985), in addition to the anticipated graphitic carbon. This further underscores the complexity of the chemical and structural definition of combustion products.

Goldberg (1 985) has discussed the question of defining black carbon, one of the major classes of combustion products, and proposed the following definition: "an impure form of the element produced by the incomplete combustion of fossil fucls or biomass. It 22 contains over 60% carbon with the major accessory elements hydrogen, oxygen, nitrogen,

and sulfur.?' The informal terrns "charcoal" and "soot" have been adopted by Goldberg

(1985) for biornass and fossiI fuel residues, respectiveIy. Goldberg (1985) also points out

that terminology and definitions tend to be specific to the method of analysis used.

Consequently, atrnospheric literature, for example, contains many references to elemental

(or "graphitic") carbon, because thermal methods have been used to quanti@ the carbon;

or to "black carbon" where optical rnethods of bulk measurement have been used.

Similarly. paleoIimnologists who rely on microscopy as an analytical method use

individual carbonaceous particles as their unit of analysis and quantification. The

multiplicity of methods, units and terms related to combustion and carbonaceous particles

has caused some difficulties in comparing studies from various disciplines, but

microscopy tends to be employed to varying degrees by most, and is in a sense the commun methodological denominator. For example: BaiIey et al. (1984) and Sheridan et al. (1 990) captured particles in their studies of pollution in the arctic atmosphere and used

light and electron microscopy ta investigate particle details. Griffin & Go ldberg ( 1 979,

19s 1) conducted geochemical studies of Lake sediments and used light and electron microscopy to aid in the interpretation of their results.

2.13. Combustion particle types

Combustion particles have been studied for a variety of reasons including: evaluating &el and burner performance (Ramsden, 1968, 1969), understanding combustion chemistry, addressing occupational health and safety concerns (Fisher et al., 1978a, b;

Schlenker & Jaeger, 1980), as factors in understanding and assessing environmental 23 pollution (Giever, 1968; Davidson et al., 1974), and as a branch of materials science dealing with by-product utilisation (Bailey et al ., 1990; Campbell, 1990; Etiegni et al., 1991).

Combustion particles have been studied at source (Bolton et al., 1975; Cheng et al., 1976;

Cachier et al., 1985): at outlet (Carpenter et al., 1980): on emission (Graedel et al., 1993), in the atrnosphere (Davies, 1974; Cachier et al., l989), in transit (Delany et al., 1967; Folger,

1970): on deposition, in snow (Noone & CIarke, 1988) and on vegetation. Combustion products have been retrieved frorn air (Brosset, 1976), precipitation (Brimblecombe et al.,

1986), vegetation surfaces, glacier ice (Chylek et al., 1987, 1999, lake and ocean sediments

(Hites et al., 1977; CharIes & Whitehead, 1986; Charles & Hites, 1987), and human lung tissue (Fisher et al.. 1978). They have been colIected Iocally, meaning in dose proximity to an identified source (Herrick & Benedict, 1968); in remote regions, far from knowi emitters

(Cadle & Dasch. 1988) and in urban areas (Gatz, 1975). This diversity of researcli approaches reflects the interests of many different disciplines wit1-i different methods, definitions and objectives. One of the most significant problems I encountered on entry to this field \vas that of interpretation: there are few standard definitions, a wide range of methodologies exist, methodological efficiency ofien appears to determine the criteria chosen for evaluation, and there is reiatively Iittle agreement between disciplines as to what the key questions are with respect to the study of combustion particles in the environment.

Recently this has begun to change, with increasing numbers of interdisciplinary meetings, particularly in relation to arctic contarninants (Wallén, in Stonehouse, 1986; Landers et al.,

1995), but also on other topics such as biomass burning, where clarification of terrns and uniforrn definitions have been called for (Clark et al., 1997). 24 wide-ranging uses of combustion technologies, the variability of combustion technology designs, and the chernical and physical complexity of the fùels burned. This results in a high degree of specialization in research applications. Fuels include solids, liquids and gases.

Solid fuels such as wood and cod are highly heterogeneous in terms of their composition. combustion characteristics and particularly their combustion products, and liquid fuels may aIso produce a variety of combustion particles. The problem of combustion particle description and classification is the subject of Chapter 3 (see in particular Chapter 3, Plates

1,3 and 3).

2.14. Atmospheric transport of pollutants in the Arctic

In the Arctic, aunospheric science has played a key role in the investigation of transport and origin of pollutants since the first airbome observations of the phenomenon of arctic haze' in the 1950s (Mitchell, 1956; Barrie, 1985, 1986; Barrie & Hoff, 1985; Pacyna

& Shaw, 1990; Pacyna, 199 1; Sturges, 199 1). Combustion particles have been identified as a component of arctic haze and the seasonal variability of the haze has been correlated with the position of the arctic front (Daisey et al., 198 1). The presence of combustion particles, sulfates, polycyclic aromatic hydrocarbons (PAH), and trace metals has contributed to the unravelling of the mechanism by which the southtvard expansion of the arctic front in

' The phenomenon of "arctic haze" is an atmospheric condition of stratified air masses observed in springtime in the Arctic in which particle-rich layers, derived from long- range transport, appear as dark or reddish-yellow bands; depending upon the orientation of the observer in relation to the position of the Sun. Arctic haze was observed by airborne reconnaissance missions in the Arctic in the early 1950s, and reported by MitcheI1, 1956. According to Sturges, 199 1, Inuit who came in contact with the Croker Land Expedition of 1914 were farniliar with this phenomenon and termed it "poo-jok". This is a very interesting observation, as it implies observation of long-range transport in the Arctic dating from at least WW L, as contrasted with the post-W.W.11 date usually estimated. 25 unravelling of the mechanism by which the southward expansion of the arctic front in winter into the industrial and agricultural regions of southern Canada and the northern

United States essentially serves as a seasonal vacuum cleaner, conveying submicron-sized particulates and gases into the high latitudes, where they are then deposited, or fkrther transported,

As a result, in part, of the program to establish the Joint Canadian - United States

Weather Stations, which began in 1946 (Dunbar & Greenaway, 1956) and led to stations being built at Aiert, Eureka, Isachsen and Mould Bay, Canadian and American scientists have had arctic research capabilities for over 50 years. These arctic weather stations have become the front Iines for studies of atrnospheric chemistry related to sources and pathways of contaminants in the Arctic (Barrie. 1986; Barrie & Hoff, 1985; Barrie et al.,

1992). and nluch of our understanding of the importance of Eurasian influences is due to this work. For a comprehensive review of atmospheric contaminants research in the

Arctic, the reader is referred to Barrie, 1986 and Barrie et al., !99l In addition, atmospheric studies in other areas of the Arctic (Ottar et al., 1986; Shaw, 1991 ; Pacyna &

Shaw, 1990) have also made significant contributions to Our understanding of the behaviour of particulates resulting from natural and anthropogenic combustion, as well as dusts (Rahn et al., 1977; Winchester et al., 1984), particularly those associated with long- range transport of atmospheric pollutants. Although much of the atmospheric research in the Arctic is directed to the sub-micron sized particdates (Pueschel et al., 1995), so- called "giant particles" (greater than 2 microns in size) are also of concern to atmospheric studies (Winchester et al., 1984; Radke et aI., 1984a, l984b), given their contribution to 26 particulate mas, as well as their utility in interpreting possible sources in order to explain

chemical signatures obtained through bulk analyses (Daisey et ai., 1981 ; Bailey et al.,

1984; Sheridan et al.. 1990; Shaw, 1991). "Ultra-giant particles" (NO ym) are reported to

heights of 5 km, are "ubiquitous" in distribution, although most frequent near the ground, and while consisting of anthropogenic combustion particles as well as cmstal dusts, do not correlate with arctic haze layers (Radke et al., 1984a, Bailey et al., 1984).

2-15. Effect on health, ecology and economy

In addition to the impetus for atmospheric study of combustion particulates due to interest in long-range transport, much current knowledge of biological effects has resulted from concem for human health tliat may be adversely affected by high concentrations of combustion emissions from local sources. Many early particle-sizing techniques were developed by researchers concerned with particulates in coal dust in mines and in smoke from industrial processes. Dusts are problematic due to their explosive potential, which is also associated with the risk of mine fires. in the case of coal. Dtists and smoke effluents are of concern for reasons of public health associated witli inhalation of particulates, particularly those smaller than the PM10 and PM 2.5 standards. ' Coal dusts are known to cause "black lung7' disease, due to physical obstruction of oxygen exchange in lung tissues, and combustion particles can have similar effects, Ieading to increases in asthma, cardiovascular disease, and other related conditions.

' These standards refer to particulate matter (PM) in air within the range considered to be respirable, specifically for particles having diameters of 1O Pm and 2.5 Pm respectively. Particles in these size classes are held responsible for increased cardiopulmonary disease and death rates (Masood, 1996; Reichert, 1996; Staff. The Economist, 1995). Combustion particles are frequently associated with carcinogenic compounds, and

are therefore of concern with regard to long-term health effects, such as increases in

cancer rates, a relationship first observed in the case of chimney sweeps in London,

England, and the high incidence rate of scrotal cancer which they suffered (Buce, 1990).

The adsorbent properties of carbon are well known, and these qualities may result in the

accumulation of atmospheric contaminants on particle surfaces during transport, making

these particles a vector for the introduction of contaminants into the arctic environment,

as well as a source of "inherent" contarninants such as PAHs, which are intrinsic to many

forms of combustion products as a result of the chemical composition and transformation by

combustion of fuel feedstocks (Natusch et al., 1974). Similarly dust and combustion

particles cm cause physical obstruction of gas exchange functions in vegetation, for

example by blocking stomatal openings, and causing many other forms of damage

(Williams et al.. 1971; Smith, 1974). and can affect animal health through physical and

chemical effects like those described for human health (Piperno, 1975; Fisher et al., 1978).

It should also be noted that growth-promoting effects of substances found in

association with atmospheric pollutants, such as carbon dioxide, sulphur and iron, have

been observed. Although these consequences are not our pnmary concem at this time, given

the effects of some limiting factors, it is not unreasonable to anticipate that some trace

elements found in efnuents may serve to promote growth (see for exarnple Harvey, 1933,

1937; Hein et al., 1995) and that some ecological impacts of airbome contaminants may be

espressed as growth (Keeling et al., 1996; MacKenzie, 1995), particularly when a trace contaminant also serves as a trace nutrient, 28 In economic tenns, in the urban environment, combustion particles constitute an

important part of the fallout which occurs, soiling and degrading building materiais, and

constituting a nuisance and economic cost for urban dwellers (Vandegrrift et al., 197 I ;

Hamilton & Mansfield, 1993). In the Arctic, however, this problem is more likely to be

experienced in locations were there is a significant local pollution problem, such as toms

like Provendya, Sibena, where coal-fired cornrnunity generators have blackened buildings

(C. Gray, pers. commun., 1999), rather than in relation to diffuse particulate loads resulting

from long-range transport.

2.16. Combustion particles in the environment

Atmospheric scientists, especiaIly John Aiken, with his investigation of the properties of condensation nuclei in air at various elevations and locations, developed the equipment and made the observations that Ied to modem studies of atmospheric particulates. One of the earlier case studies of larger atmospheric particles in relation to location and human activity is that by Coste (1936) who had also identified the creation of nuclei from combustion, reported suIphuric and nitrous acid in London air and recoçnized that in nature, sea salt was the primary source of condensation nuclei in non- urban areas. In his paper in 1936, Coste identified a number of classes of burned and unburned particles resulting from combustion, including silicate spheres, sintered particles, particles with "the characteristic foani structure of coke and sometimes covered with minute spheres of ash", hollow spheres from pulverized fuel, with or without gas inclusions, "long sintered particles", "unburnt coke", and "magnetic oxide of iron in spheres or sintered fragments". This is an impressive inventory, as it covers most of the 29 particle types reported by other researchers studying coal combustion subsequently. This paper also reports the results of a study of particles collected at a number of sites,

including London parks, Kew, Teddington and its railway station, Battersea Park near the power plant, and Cockington near Torquay. It is particularly interesting as an environmental study, providing a first evidence of the pattern of decay with distance from source of the distribution of industria1 combustion products in the environrnent: sarnples from the London parks contained a number of particles which Coste attributed to industrial pollution, while those from Torquay contained sand, soi1 and bioIogica1 remains. Coste also offered a comment on the emission controls at Battersea Power Plant, saying that the low level of spheres found showed "the efficiency of the gas washing plant?'.

Environmental studies were relatively unusual in the early stages of the development of the field of combustion particle research, which was more heavily influenced by studies of industrial dust, smoke and ashes at their sources (Green, 1936;

Patterson & Cawood, 1936; Lessing, 1930). However the nuisance and health concems surrounding installation of central electrical generating facilities did precipitate early research into control measures (Lessing, 1930; EIectricity Commission, 1932).

The state of knowledge with respect to coal combustion and particulate emissions at this time \vas such that four factors were known to account for the characteristics of the resultant ash:

1) combustion rates and processes

2) boiler plant and flue design 3) the composition of the original fuel, in terms of minera1 content

4) fuel combustibility and size, meaning physical and chemical features, including volatile matter content (Electricity Commission, 1932).

These factors are still the basis for the design and management of fuel burners today (Chomiak, 1990), althouçh the theoretical framework of combustion chemistry has undergone significant change (Chomiak, 1990).

Attention kvas diverted from combustion particle studies by World War II and the related emphasis on increased industrial production. but following the end of the war, a new era of particle studies began. An extensive review of al1 literature related to particle studies applicable to combustion particles is beyond the scope of this chapter; however, the interested reader is referred to important works by DallaValle (1948), Orr &

DallaValle (1 959), Herdan (1960): Cadle (1975), Stem (1976) and Hinds (1982), for esarnple. wliich provide comprehensive reviews and discussion of the theory and methods of particle study, including sampling?measurement and statistical analysis, particularly in relation to atmospheric particles.

2.17. Emissions

Not al1 particles produced in coal burning or in other forms of contained combustion will be emitted: some will be retained in the bottom slag, some will contact bumer or stack walls and become hung up, and some will be trapped by emission control devices, depending on the state of development of the bumer. The efficiency of particle removal by emission controls such as bag houses, electrostatic precipitators, and amendment of stack gases is highly variable, witli the best results achieved by 3 1 electrostatic precipitators operating under ideal conditions which are capable of retaining

over 95% of particulates greater than 1 pm in diameter. Unfortunately many of the

regions utilizing the greatest arnounts of coal are not using state-of-the-art bumers or air

emission control units. Even those that are in place have to deal with the emission of fine

partides and gases which then coagulate and condense to form larger particles. With

improved collection efficiency. fewer particles are available for transport at the source

concerned, but because the consumption of fuels continues to increase and much of this

growth is in regions which lack stringent controls, the amount of particulate matter

undergoing transport globally in absolute terms is Iikely to continue to increase

(Chorni&, 1990).

2.18. Long-range atmospheric transport and tracers

One of the more intriguing applications of study of airborne particles, including

combustion products, is the determination of source areas for deposits suspected of

having undergone long-range transport. The phenomenon of transport of particulates has

long been familiar to sedirnentologists and to physical geographers studying sand and

loess deposits. A deeper appreciation of the potential for long-range transport of particulates began to develop when Delany et al. (1967) who, while searching for uncontaminated air for purposes of studying microrneteorites, discovered the phenomenon of transport of particulates from Africa to Barbados, by the trade winds.

Delany et al. (1967) also remarked on the presence of combustion particles, described as

'cokey balls', when observed with light rnicroscopy, which they attributed to smoke produced by ships. These observations encouraged a number of Iines of inquiry, including 32 work by Parkin et al. (1970) and Folger (1970) who conducted Atlantic Ocean studies by boat. Indeed, these appear to be the first studies since that of Coste (1 936, referred to above) to apply the occurrence of combustion products in atmospheric sarnples to the interpretation of meteorologica1 conditions, long-range transport and origins, recognizing the potential of combustion emissions in particular to serve as tracers of air-mass movements on a very large scale.

Studies of transport of pollen, dust, smoke arid related meteorological phenornena have provided evidence of passive long-range transport as a result of emissions and meteorological conditions from al1 parts of the world. Studies of pollen by Tydesley, 1973a, b; Fredskild, 1984; Bourgeois et al., 1985; Bourgeois, 1986,

1990; van der Knaap, 1987, 1988; and Hjelmroos & Franzén: 1994; of dust by McCrone

& Delly, 1973; Parkin et al., 1970; Shaw, 1980; Parrington et al., 1983; and Pacyna &

Ottar. 1989; of volcanic dusts by Robock & Matson. 1983; of hazes by Bridgeman et al.,

1989 and of smoke by Taylor et al.' 1996; Cofer et al., 1997; and Garstang et al., 1997; provide interesting esamples. Events like the brown snow deposition in the Central Arctic reported by Welch et al. (1991) as well as the dust deposited at Barbados (Prospero,

1968) and in the North Atlantic (Parkin et al., 1970; FoIger, 1970) ofFer exarnples of long-range atmospheric transport of complex deposits consisting ofcrustal materials, combustion pollutants and biological particles, in a range of enviromments remote fiom industrial centres. An interesting historical example is provided by Brïmblecomb et al.

(1 986) which suggests that even in 1862 and 1863, a time when consumption of coal was much lower than at present, long-range transport and deposition of combustion particles 33 in the form of "black showers" occurred in the Cairngoms, a remote mountainous area of

Scotland. Tranter et al. (1985) gives a modern esample of a black snow in the sarne region, describing the associated particulates as "pulverized fuel ash and black carbonaceous residue". Taylor et al. (1 996) found evidence of biomass burning, believed to originate in eastem Canada, throughout an ice core taken at GISP2 in Greenland. In addition to providing evidence that such transport does occur, sometimes over long distances (100s and 1000s of kilometers), these studies also help to explain some of the parameters affecting transport (McCxtney, 1994).

Studies of transport of chemicals, including lead isotopes, trace elernents and organoclilorines in air masses by atmospheric chemists have also contributed to the understanding of sources and mechanisms of transport of pollutants in the Arctic (Hopper et al., 199 1 ; Maenhaut et al.. 1989; Nriagu et al., 199 1; Wania & Mackay, 1993).

Precipitation in the Arctic has been studied in order to determine whether natural and/or antliropogenic inputs could be detected from rneasurements of environmental sampIes or through paIeoecological cornparisons of previous and contemporary conditions (McNeely & Gunmer, 1984; Koerner & Fisher, 1982; Gregor et al., 1995).

Koerner & Fisher (1982) found that there had been a significant increase in acidity in snows deposited on the Agassiz Ice Cap in the previous 25 years which did not correspond to known volcanic activity, and could be most reasonably attributed to anthropogenic influences. Gregor et al. (1995) found a range of values for PCBs in a 30 year record from the Agassiz Ice Cap, but no clear temporal trend in that period.

2.19. Combustion particle characterization 34 In the literature there is one obvious and fiindamental methodological division in

emissions research: that between chemical and optical methods of analysis (Goldberg,

1985). Both approaches are relevant to the study of combustion particles, as we are

concerned with form, detennined on an optical basis, as well as structural elements that

are related to forrn. However, in general, chemical methods are less concerned with the

appearance or behaviour of individual particles, and for purposes of paleoecological study

of occurrence in cornparison with other discrete entities, optical methods, specifically

microscopical methods are preferred.

Studies of coal combustion particles have investigated particle types in relation to

the characteristics of particular coal deposits (for example, Watt & Thorne, 1965). At the

other extreme. Vandegnft et a1. (197 1) surveyed combustion particles as one class of

particles emitted from various industrial sources in their comprehensive study of particuIate

pollutants.

While non-black combustion particles have been observed in particle studies in the various disciplines cited above, the main focus of paleo1imno1ogical studies of anthropogenic combustion has been on black spherical carbonaceous particles (Gnffin &

Goldberg, 1979, 1981 ; Renberg & Wik, 1984, 1985a, b; Rose, 199 1, 1996). There are a number of compelling arguments in favour of using the black carbon component of combustion ernissions which have been articulated by these researchers, including ease of chernical separation (Rose, 1990), and ease of counting at low magnification (Renberg &

Wik, 1985a). At the outset, 1also intended to restnct my investigation to spheroidal black combustion particles. However, recognizing that combustion products are generaIIy 35 heterogeneous, depending on factors such as fuel type and composition, burner type and conditions, and flarne temperature, enhanced by my observation of the diversity of particles collected Rom known arctic sources, as weli as reports of a range of combustion particles ftom arctic studies in the literature, encouraged me to ask whether a broader array of combustion particles might be usefully investigated. These observations, coupled with work by Fisher et al. (1978) who demonstrated the classification of opaque and non-opaque coal burning particles using light microscopy, inspired me to investigate an even broader array of combustion particles in lake and pond sediments from arctic sites.

A wide range of combustion products has been described by McCrone & Delly

(1973) and by Hamilton & Jarvis (1 963) in their comprehensive studies. The diversity of these particies is such tliat most descriptions note a range of products, rather than a single particle type. In the face of this vast population of combustion particle types, it becarne clear that while a comples hierarchical classification might be possible (Appendix 3. l), in terrns of paleolimnological application, a simplified, artificial, fünctional classification emphasizing characteristics which can ultimately be related to factors such as size, shape or composition- which could then be interpreted in relation to ecological effects, transport, or ongin for example, could be a usehl intermediary step. In this regard, the work of Fisher et al. (1 978) is noteworthy in having established, for coal-burning emissions onIy, a comprehensive classification of carbonaceous and non-carbonaceoiis particle types based on morphology. This work provided the inspiration as well as a usefül starting point for my efforts to deveiop a functional classification of combustion particles found in the arctic 36 environment, encompassing particles fiom a wider range of combustion fùels, including oil, diesel, and charcoal, in this thesis.

Other researchers (Griff~n& Goldberg, 1979, 1981 ; Rose, 1991 ; Rose et al., 1995,

1996; Stoffyn-Egli et al., 1997) have linked combustion particles to fuel types by using

SEM to analyze the surface features and shape of the black carbon component. Griffin and

Goldberg (1979, 198 1) found shape and surface features to be distinctive indicators of fuel type, with sphericity held to be the single most important characteristic of fossil fuel combustion particles (Griffin & Goldberg, 1979, 1981). However, other researchers have raised some doubts about the exclusiveness of the Iink behveen spheroidal particles and fossil fuels, as spheroidal particles have been found in sediments pre-dating fossil fuel usage

(Clark & Patterson, 1984; Patterson et al., 1987), and in non-fossil fuels ashes, such as wood (Komarek et al., 1973; Hueglin et al., 1997). Indeed, many combustion-related particles that are non-carbonaceous are spheroidal, with sphericity signifj4ng production at relatively high heat, where droplets are espanded by gases evolved during heating.

Pawley & Fisher (1 977) note that the morphologies described using scanning electron microscopy (SEM) may appear very similar, but the elemental composition may be quite different. Spectroscopie detectors, using s-rays to generate elemental spectra coupled with SEM, have contributed much to the description of discrete particles and their chemical composition. Unfortunately, as combustion particles are ofien composed of carbon and related light organic compounds, the spectra produced sometimes contain relatively little information, and attempts to reconcile particles observed microscopically with chemical profiles arrived at through bulk analysis methods have met with varied degrees of success 37 (Daisey et al., 198 1). More recently, with improved detection capabilities, this approach has produced convincing evidence linking specific fly ash sources with combustion particles found in the environment (Rose, 199 1; Rose et al., 1996).

Given that black carbon particles may represent up to 30% of the total coai combustion particles produced (Stach et al., 1973, but are more likely to contribute 10-15% or even Iess, broadening the range of particles considered means that it is reasonable to expect that a greater percentage of the total number of particles emitted by coaI burning will be included. In addition. combustion particles related to other fùel types and burners wil1 also be considered, which should enhance the investigative and analytical capacity of this approach in a region where relativeIy low levels of total emissions are found.

The next chapter of this thesis is the application of this broader approach to classification of combustion particles for use in paleolimnologica1 investigation in order to espand knowiedge of the record of combustion particles in arctic sediments. From this beginning. I hope that paleoecologica1 studies of the distribution and abundance of anthropogenic and naturaI combustion particles in arctic lake sediments wi!l also contribute to the curent debate about sources, sinks and pathways for long-range transport. CHAPTER 3

ATLAS OF COMBUSTION PARTICLES: A PRELIMINARY SURVEY OF

COMBUSTION PARTICLES AND APPROACH TO PALEOECOLOGICAL

STUDY OF THESE PARTICLES IN LAKE AND POND SEDIMENT

3.1. Introduction

At the outset, 1 intended to focus primarily on spheroidal carbonaceous particles following the esarnple of researchers such as Griffin & Goldberg (1979, 198 l), Renberg

& Wik (1 934, 1985) and Rose (1 99 1, 1996), in order to reconstruct combustion profiles for the sites selected on the arctic transect from AIert to the Belcher Islands. However in the process of assembling reference particles and inventorying combustion particles in sediments from the cores which 1 analyzed, 1 began to see a wide range of particle types related to combustion. This in turn raised the question as to whether I might be able to document. classifi and recognize a wider range of combustion partide types in the environment for paleolimnological study. This led me to the results presented here, including a report on combustion particles in relation to fuel and burner type with special reference to the Arctic, a preliminary survey of combustion particle types in lake and pond sediments from selected arctic study sites, and two different approaches to classification: one a form of descriptive cataloguing, which could be developed into an artificial key, and the other intended to categorize combustion particles in lake and pond sediments so that the resulting categories of particles could be compared in tenns of possible origin, fuel-source and environmental change. In the case of the first approach to 39 classification, a drafi of an artificial synoptic key has been appended to the thesis as

Appendix 3.1. The functional classification strategy is set out under "ResuIts" below.

1 made the decision to rely primarily on rnethods of light microscopy (LM), particularly polarized light, as the fundamental instrumental technique to establish categories for purposes of classification because it is widely accessible and relatively inespensive. However, 1 did make use of scanning electron microscopy (SEM), coupled with energy-dispersive x-ray spectroscopy, from time to time to investigate selected sarnples. The classification that 1 am using to document the occurrence of combustion particles in lake and pond sediments cmbe conducted solely with LM and does not reqiiire the use of SEM. However, the power and usefulness of SEM, particularly in confirming particle structure and composition, made it a valuable technique for reinforcing observations with LM, particularly wlien learning particle identification skills.

In the review of literature in Chapter 2,1 reviewed selected works from a number of fields relevant to the environmental interpretation and reconstruction undertaken in the applied component of this study. including combustion, contaminants, paleolimnology, paleoclimatology, meteorology and fire ecology. A brief review of tliat portion of the literature dealing with description and classification of combustion particles, using microscopy, is presented here. This section includes aspects of light microscopy relevant to combustion particles; description of combustion particles related to specific fiels, including coal, oïl, and tvood; some of the physical and chemical transformations in fiels and related materials at high temperature; and environmental studies of combustion particles, in transit in the atmosphere, and following deposition in the terrestrial or 40 aquatic environment. The papers referred to here are those that 1 have found particularly

helpful in developing an approach to the study of combustion particles in sediment

sarnples, and to problems of classification.

The remainder of the chapter esplains the process of particle analysis that 1 used

to address the problem of classification and presents the results of this prelirninary survey

of particles in terrns of an artificial classification of combustion particles. The criteria

used to develop the artificial categories are discussed below.

This chapter illustrates the diversity of combustion particles that 1 have included.

It also provides a bnef review of the literature specifically related to combustion particle

identification, as well as an illustrated survey of combustion particle types in relation to

fiiels and combustion processes. Environmental samples from selected sites between

Alen and the Belchers Islands are also presented. The artificial synoptic key (Appendis

3.1) summarizes the diverse features of particles identified in the combustion samples studied. The simplified key included in the test of this chapter under Resulrs is intended primarily for paleolimnological applications-

3.2. Microscopy of combustion particles

Light rnicroscopy, supplemented by electron microscopy and chernical methods, has been widely used to describe and classifi combustion particles (Hamilton & Jarvis,

1963; McCrone & Delly, 1973; Grasserbauer, 1978), and to investigate specific fuel products (Lessing, 1930; Rose, 199 1, 1996) and environmental samples (Coste, 1936). In addition to the general reference works on particle study such as Knimbein & Pettijohn

(1938) DallaValle (1 948), On & DaIIaValle (1 959), Herdan (1 960), Cadle (1 973, Stem 41 (1976)' and Hinds (1982), studies by McClung Jones (1950, 1967), McCrone & Delly

(1 973): Burrells (1 977) and O'Brien & McCully (1 98 1) provide particularly usefül handbooks which explain techniques and methods for light microscopy that can be applied to combustion particles.

Recognizing that combustion particles can be produced from a wide range of industrial, domestic and natural processes, and that a wide range of fuel and particle types are possible, 1 have used reference materials for comparison with samples, as well as literature, from a wide range of sources. A bt-ief survey of key publications from various fields dealing with combustion-related particles and their identification and classification follo\vs.

Of the conventional fuels, coal and products of coal burning are perliaps the best known. judging by the large number of publications that esist. Good introductions to coal as a cornples organic rock are given by Moore (1930) and Van Krevelen (1964). Useful reviews of various aspects of coal combustion and its consequences are provided by the

Science Research Council(l976). Stoker (1 976): Green (1 980), and Merrick (1984). In terms of microscopical features of coal, the references 1 have round especially valuable are Stach et al. (1975), for their illustrated treatment of coal petrology, including coal combustion particles. as well as Lightman & Street (1968); Fisher et al. (1 978) and Gay

(1984)' for their valuable categorizations of coal combustion particles.

Biomass burning has been widely studied (Byram, 1957; Bassini & Becker, 1990;

Bauhau et al., 1993; Bradshaw et al., 1994)' as discussed in Chapter 2, and the microscopy of wood and other plant tissues is well known. The microscopy of biomass 42 combustion particles as a distinct field of inquiry is relatively recent: the earliest comprehensive p hotographic survey of biomass combustion particles that 1have found is that of Komarek et al. (1973). A volume edited by Rowell & Barbour (1990) gives a thorough treatment of archeological wood in various stages of preservation, in particular chapters by Hoffmann & Jones, on structure and degradation processes in waterlogged wood. and by Hedges, deding with wood chemistry, are useful as they contain many illustrations. Hoadley (1 990) gives an excellent introduction to the identification of woods based on microstructure. Wliile it is rarely possible to identify the micro-fragments of wood charcoal found in lake and pond sediments in the High Arctic down to species due to the very smalI size of the specimen, it is possible in some instances to recognize cellular structures indicative of coniferous or angiospermous trees, or of sedges or crasses. Perhaps the best review of paleoecological studies of charcoal is that of Patterson b et al- (I9S7), although there have been many studies following this review. A recent comprehensive treatment of studies of biomass con~bustionin the sedimentary environment, including a more recent review of paleo-charcoal studies, is given by Clark et al. (1994). Hueglin et al. (1997) have studied the morphology of wood particles and describe a range of particle shapes in the fly ash, including spheroidal particles and irregular particles which they describe as "compact particles with fractal-like dimensions close to 3". They aIso note the presence of uncombusted submicron-sized particles.

Diesel and fuel oils are more recently developed fùels than wood and coal, and relevant literature comes primarily from studies of interna1 combustion engines (such as

Ebert, l985), power generation (for esample, Bacci et al., 1983), domestic heating (for 43 example, Sabbioni & Zappia, 1993), and from studies of emissions and air polIution (for

exarnple, Henein, 1976; Goldstein & Siegmund, 1976). Where morphological studies are

specifically conducted, they are more likely to use electron than light microscopy, as the

fiindamental particle units are submicron-sized carbonaceous particles showing various

degrees of crystallinity (for exarnple, Stevenson, 1982; WiIliarns et al., 1989). Studies of

particles forrned by aggregation of fine carbon are found (Medalia & Heckrnan, 1963),

and although electron microscopy was used to study these aggregates, many of the

problems encountered, such as determining particle boundaries, are sirnilar to those 1

encountered with light microscopy of irregularly shaped particles.

En addition to the materials that serve as fuels for combustion, there are other

categories of materials which may contribute to emission of combustion-related particles,

including the category of materials processed through combustion, such as incinerator,

smelter and foundry operations (Vandegrifi et al., 1971): and combustion arnendments,

such as catalysts and emission modifiers (McCrone & Delly, 1973). Catalysts and related

materials are not produced by combustion as such, nor are they created by combustion,

but they certainly are comected to combustion, and as emissions, cm be said to result

from combustion (McCrone 22 Delly, 1973). As evidence of specific types of combustion,

1 would argue for their inclusion in the study of combustion particles in the environment.

Incinerators produce perhaps the most varied range of combustion-related particles (McCrone & Delly, 1973), which is not surprising, given the heterogeneity of the matenals burned. What is surprising is that there is Iittle recognition of incinerator emissions in environmental research. Indeed, incinerator emissions have been excluded 44 from at least one national study of particulate emissions related to combustion

(Vandegrifi et al., 197 l), even though this same study recognized incinerators as major emission sources (Vandegrifi et al., 197 1).

For some classes of combustion particles, an analogy can be drawn with the process of glass making where mineral substances are heated to form an amorphous glass.

Materials passing tlxough combustion processes may be exposed to high temperatures that may cause various p hysical and chernical changes, including transformation of minera1 species. The products that result may be amorphous as well as crystaIIine (Fisher et al., 1978). Sometimes crystalline inclusions occur in the glass, either as a result of incornplete rnising or crystallization from the "melt". Some of the crystalline inclusions found in gIass, such as mullite, quartz, and cristobalite (Insley, 1924; Holland, 1937,

1938). are also found in coal combustion products (Fisher et al., 1978).

When I observed that polarized light rnight be useful in investigating rnany combustion sarnples, other avenues of research opened. While there is a long history of using poIarized light in mineraIogy, its application to non-crystaIIine organic substances is less well known. In addition to McCrone & Delly (1973), who describe the theory and techniques of polarized light microscopy, works by Hallimond (1953), Wallis (1965),

Bennett, in McClung Jones (1950, 1967), PhiIlips (1 97 1) and O'Brien & McCully (198 1), provide the most helpful orientations. In particular: the chapter by Bennett (in McClung

Jones, l967), which discusses the application of polarized light to biological materials, and the chapters by Florian and Hoffmann & Jones (in RoweIl & Barbour, 1990), which demonstrate the utility of polarized light microscopy of woods, were especialIy helpful. 45 Wood structure, chemistry and optical properties have cornplex interrelationships (see for example, Ritter, 1930; Bailey & Vestal, 1937; and Vermaas & Hermans, 1947), which are modified by combustion (see for esarnple, Hueglin et al., 1997).

3.3. Combustion particle formation

On the basis of the literature, a general scheme for understanding combustion particle formation can be developed as follows: an organic fiel is heated and burns, producing gases and particulate emissions, in a range of sizes and particle types related to the nature of the original fuel, the type of bumer used, and the operating conditions under which it is mn. From the work presented above, we have seen that there are two basic types of combustion particles defined by parent fuel component: those formed from liydrocarbons present in the fuel, termed carbonaceous particles; and those formed from non-carbonaceous materials which are either present in the fuel; or are added to the bumer as an aid to con~bustion,or as a waste reduction measure.

Solid fuels such as wood or coal, burn from the edges inward, fueled both by the votatile gases evolved from the fuel as it is heated, and the combustible solid. The outer layers turn to ash and faIl away, the heating of volatiIe substances continues, and the flarne front burns the evolving gases, creating a drafi in the process wliich serves to draw more volatiles to the flame. In the case of biornass combustion, the vessels themselves may become ducts through which hot gases are pulled. If the particle becomes carbonized, perhaps due to insufficient oxygen for ashing, rather than consumed, the structure of the original wood may persist, as in Plate 1, Figures 14 and 15. In the case of pulverized coal, this process of heating, gas production, flaming and burning, is repeated 46 rapidly with very srnall (-2 mm diameter) coal particles, in various feeder assemblies.

When particulates escape from the combustion zone, convection currents, resulting fiom the intense heat of combustion, cmy them aloft.

Liquid fbeels are usually burned as a pressurized spray of droplets in a closed chamber, or passively in a flarne fed with a form of wick. The droplets resulting from the spray type bumer pass through the combustion zone of the bumer, and combust at or above the droplet surface, açain as combustible volatile gases leave the droplet and bum.

Less combustible materîals, usually the larger macromolecules which are heavier and less volatile, are Lefi to form particulates from the incompIetely combusted, burned out droplets. These mechanisms are used in stationary and mobile engines and generators.

The rate of particle production is related to the nature of the fuel as discussed earlier.

The composition of the emissions ranges from single elements, such as sulphur or elemental carbon, to complex macromolecuIes, such as polynuclear hydrocarbons.

Particles may be composed of organic or inorganic constituents of the fuel, or, of a combination of the two. Particles may retain features representative of the original fuel, or may be created entirely from physical and chemical processes of combustion, or may show a mix of characteristics of the fuel particle and combustion process. Particles resulting from combustion rnay be stable or rnay continue to be transformed (see for example Fisher et al.. 1976). Once emitted from the combustion process, the particles are subjected to modification by physical, chemical and/or biologicat processes in the environment. One of the cautions that must be observed when comparing reference materials, reported in the Iiterature or in physical sarnples, with samples obtained from the environment, is the recognition that combustion particles extracted from

environmental samples may be modified as a result of taphonomic processes. This was

first noted in relation to charcoal by Patterson et al. (1987) in his review of literature

pertaining to paleoecological studies, but would be of concern in investigating al1

environmental combustion particle studies or in any study of materials that are subject to

transport and deposition, for that matter.

3.1. Materials and Methods

3.4.1. Reference Materiaïs

Reference materials from the processing and buming of a range of fuels were obtained- including: coals from various locations and coal ashes (bottom and fly ashes) from a number of coal buming power plants, domestic coal burning, oil buming power plants, diesel power plants (Caterpillar-type), domestic oil heating, open wood burning, domestic wood burning, mobile source emissions from diesel-pocvered trucks and other heavy equipment (such as diesel helicopter, CF- 10 Flex Track bulldozer, cat-tractor). and small burners fueled by mised liquid fuels. Ashes from domestic and commercial incineration were also studied, as were other types of emissions from kno~vnindustrial processes. 4 In addition, a set of commerciaIly prepared slides of combustion and

" 1 collected samples of combustion products from stationary and mobile sources in the Arctic myself. I also obtained some combustion product samples, such as those fiom Russian sources, from colleagues who collected these samples for me. In addition, 1 coIIected combustion products and related material at southern sites. As well, some combustion product samples from southern sources were donated either by other researchers, or by the facility operator, as indicated under "Acknowledgements". industrial products was also used for reference'.

3.4.2. Microscopy

This section describes the materials and methods used to prepare the sarnples used for identification and classification of combustion particles, as well as providing an overview of the treatment of the environmental samples. Further details of the methods of preparation and analysis of combustion particles in environmental samples from the study sites are included in Chapters 4,5, and 6, and in Appendix 3.2. In addition to reference slides that 1 prepared, commercially prepared slides of industrial particles (available from

McCrone, as described above) originating in combustion and other processes, were also used for reference.

Preparation of samples for microscopy followed one of two strategies, depending on the intended purpose: reference and environmental samples for analysis were digested with strong acids and bases. as described by Rose (1990, 1994), and sIide preparation techniques originally developed for diatoms and pollen, using glass slides, coverslips, and transparent rnounting media (~~rax@(n= 1 -65 wet. 1 -70 dry), PJaphraxa (n= 1-77),or glycerine gelatin (n=1.4), were used. In the case of selected reference materials, as an alternative addition to digestion and preparation as above, subsamples were dispersed in appropriate liquid media (such as distilled water or ethanol), a drop was placed on a coverslip, dried and then mounted. In both cases, the slide-making technique was the same: a drop of the sarnple in suspension in distilled water was placed on a coverslip

* McCrone Reference Slides of Combustion Products, including Incinerator Fly Ash and Catalyst, are available f?om McCrone Accessories & Components, IL 60559-1275, U.S.A. 49 measuring 22 nim by 23 mm, positioned on a slide warmer in a Class-100 Acid

Cleanhood at 7S0C,the lid of the slide warmer was closed and the coverslip and sarnple were left to dry overnight. If a permanent mount was to be made, a clean glass slide was warmed on a hotplate, a drop of rnounting medium, in this case, ~~rax@or ~a~hrax@, was placed on the slide and heated. When the mounting medium Iost some of its viscosity, the coverslip was transferred to the slide, carefully inverted above the drop of mounting medium and lowered into place. Heating then continued briefly until bubbles just began to form, at which point the slide was removed from the heat, cooled, Iabeled and stored.

The slides were analysed using a Reichert Research Microscope, fitted with a tungsten filament light source, a transformer and polarizing filters. Eyepieces of a variety of magnifications were used: 8x, 1Ox, 15x and ZOx. Objectives used were IOx, 20s and

45x

A Nikon or MinoIta camera was mounted on the camera port. The camera was fitted with a cable release. Particle counts were made using a mechanical stage, perrnitting careful control of traverses of the sIide.

Observations were made primarily with transmitted light. In addition to polarizing filters, the microscope was equipped with neutral gray, blue, and green filters. The polarizing, blue and green filters were the most frequently used. Indirect top lighting was also used as needed to detemine surface characteristics of particles.

In addition to the Reichert compound microscope, dissecting microscopes made by Wild and Olympus were used, as were polarizing microscopes by Vickers, for particle study and characterization-

3.4.3. Particle description: quantitative and qualitative aspects

The criteria chosen to document the particles and create the artificiai categones

are designed to maximize the differences between categories and minimize the variability

among particles included within the category. Quantitative variables inchde counts of

particles in environmenta1 samples and particle size as represented by particle diameter.

Qualitative variables include particle shape, structure, opacity and colour.

3.4.3. (a) Particle enumeration and size classification of environmental sarnples

The methods discussed in this section apply primarily to Chapters 4, 5, and 6, but

are also relevant to combustion particle description. For this reason, the details of the

partide counting and sizing methods are presented here. After some early trials making

transects across the microscope slide, 1 decided to count the total area of the coverslip in

order to avoid introduction of bias due to uneven particle distribution on the slide, and to

minimize the human error associated with uncertainty in selecting particles (Holdsworth et al., 1954; Herdan, 1960).

There are two important technical considerations in the quantification of combustion partides in relation to particle size, the first being the definition of what is to be considered to be a discrete particle (Holdsworth et al., 1954), and the second being the determination of particle size. The first question is not trivial because of the various mechanisms by which combustion particles can forrn, such as fragmentation, volatilization, pyrolysis, condensztion, aggregation, agglomeration and sintering, either singly or in combination, which means that a "particle" may be simple, in the sense of 51 being composed of a single intact entity, or compound, meaning composed of aggregated

material. The second question poses other difficulties partly due to technical issues

related to measurement using the microscope, as well as the time and effort required to

secure measurement of large numbers of particles. Afier exarnining many different

approaclies to particle definition, I decided to adopt a definition of particle as the smallest

discrete entity obtained without exercise of force directly on the particle. This means that

particles which have been chemically digested and physically processed through washing

and centrifugation, for esample, would be treated as individual particles regardless of

whether they had forrned through aggregation or agglomeration or similar additive

processes, from other units (Green, 1946). While it might be possible to reduce such

'Lcompound" particles to smaller entities througl-i application of force, for exaniple

crushing glassy pleurospheres between coverslips to release interna1 spheres, a particle

would be taken to be the smallest discrete unit appearing with an unobstructed margin on

the microscope slide, following processing and dispersion. In order to offset any

distortion of the results by inclusion of aggregates in the subsequent particle distribution,

shape and/or consistency were included in the particle characteristics recorded (Robbins,

I 954; Herdan, 1960).

The determination of the boundaries or particle edges for the purpose of sizing the

particles required that a standard approach be adopted due to the sphericity of many of the particles involved. Flat or plate-like particles might appear focused in one plane, but particles with three-dimensional shapes do not. For purposes of sizing, 1used the sharpest

focus of the particle edge as the outside dimension. There is an implied assumption in this 52 approach that non-equant particles will settle in the most stable position, that is, with the face having the greatest surface area parallel to the slide. Where this is not the case, the likelihood is that following the inversion of the particle-coated coverslip in the mounting medium and heating to fluidity, the particle will "fall" into a more stable position. In the case of irregularly shaped particles, 1 followed the method of Medalia & Heckman (1 969) and took the discrete margin as the edge of the particle.

The next task uras to select a method of establishing size classes. While there are limitations in the analyses which can be performed on such classified data, in the case of atmospheric particles at least, the use of size classified fractions is routine, given the reliance on cascade impactors and other size-restrictive sampling devices, and does not appear to hinder interpretation of the resuIts (Cadle, 1975).

There are two standard approaches to measurement of particle size using the microscope: particle dimensions, usually a specific diarneter6, are either measured using a filar eyepiece or stage micrometer; or the particle is compared to a shape, usually a circle of known size. This can be done using a projection of the image or through the microscope with a special graticule mounted in the eyepiece of the microscope. Based on reviews of size class measurement (Fairs, 1943, 195 1 ; Heywood, 1946; DallaValle, 1948;

Hamilton et al., 1954; HoIdswoah et al., 1954; Herdan, 1960; Giever in Stem, 1968;

There are two diarneters commonly used to describe particle size: Martin's diameter, which approximately bisects the area of the particle (Herdan, l96O).; and Feret's diarneter, which is the mean distance rneasured along an imaginary line joining tangents on opposite sides of the particle, the same set of tangents being used to define this distance for a11 particles (Giever, in Stem, 1968). Some preference for the use of Martin's diameter has been expressed (Heywood, 1946; Herdan, 1960) but Feret's is still recognized (Giever, in Stem, 1968). 53 Cadle, 1975; McCrone & Delly, 1973): E decided to use the British Standard (Globe and

Circle) Graticule, one of the "globe & circle" type graticules, based upon that of Patterson

& Catvood (1936).

The British Standard (Giobe and Circle) Graticule consists of two series of seven

"globes" or solid circles and seven "circles" or open circles, arranged in order of

increasing diameter paraIlel to a central rectangle. divided into smaller rectangles (see

Appendix 3.3 for an illustration). At 200x rnagnification, the diarneters of the globes and circles are 3.3, 5, 7, 9, 12, 19, and 28 Fm. Class intervals are non-uniform, with the lower classes representing a narrotver range of values of diameter, and higher classes representing a wider range of particle diameter values. The reason for this arrangement of size class ranges is to reduce the influence of the very small particies which are relatively much more abundant numerically. Also, where estirnates are to be made for surface area or n-iass. derived from calculations based on numbers of particles, the effect of relatively few but very large particles distorts the distribution. Generally, large particles form a relatively small fraction of the total particle sample in terrns of absolute numbers, but because of their relatively much greater area and mass, can drown data from categories of smaller particles if estimates of particle mass are made. Particles larger than 28 Fm were sized using the rectangles in the centre of the graticule.

As atmospheric size distributions have a wide range of orders of magnitude of particle diameter (up to 1 03, Cadle, 1975), and as 1 expected to deal with particles delivered by atmospheric transport, ranging between 1 pm (the lower limit of resolution of the light microscope) and LOO Fm+ in diameter, 1 decided to use open ended size 54 classes for the smallest and largest particles. and to use the "circle" diarneters for the class endpoints. This resulted in the establishment of eight size classes with the following range of diarneters (at 200x magnification): c3.3 to 3.3 Fm, >3.3 to 5 Fm, >5 to 7 Pm, >7 to 9 Fm, '9 to 12 Fm, > 12 to 19 Pm, > 19 to 28 Pm, and >28 Pm. This procedure gives a continuous range, providing greater certainty as to the sizes included than using the circles of the graticule alone to delimit size classes (Green, 1936).

In this way, particles near the Iimit of resolution of the microscope could be included without imposinç false accuracy as to size, and very large particles could be included while restricting the number of classes used, thus minimizing the number of

"empty?' classes likely to be encountered.

The benefits that accrue from size classification include improved eficiency of size determination and the production of distribution data that is replicable and comparable. 1 did attempt sizing of particles using direct measurement with a calibrated stage micrometer as well as size classification with a calibrated eyepiece graticule, and the deciding factor was operator time: it took 30 days to count and size samples from the

Lower Dumbell Lake core (see Chapter 4) with the stage micrometer measurement approach, and 8 days using the graticule size classification technique.

3.4.3. (b) Qualitative factors: functional and artificial particle classification and terminology

The properties of particles most readily determined with light microscopy that 1 have found most usehl in obtaining information usefil for categorizing combustion particles are shape, structure, opacity and colour. On the basis of these features, 1have 55 prepared a simplified artificial diagnostic scheme, represented by a graphical key, as well as an espanded version in the form of what Pankhurst (1979) tems a "synoptic key" which 1 have used to address the problem of dassification of environmental combustion particles whose origins are not known. WhiIe it might be questioned if the classification of such particles according to an artificial key in the absence of information as to source is meaningfùl, 1 would draw an analogy with the position expressed by Duff et al. (1995) with regard to chrysophycean cyst classification, where the argument was eloquently made for the benefit of describing cysts in the absence of clear taxonomic data.' In order to distinguish the cysts, they may be given an artificial genus name (following Nygaard,

1956. cited in Duff et al. 1995), or a number based on a system of numbering unknown cysts. each with its unique description (International Statopore Working Group (ISWG);

Cronberg & Sandgren, 1986, in Duff et al. 1995). The situation of combustion particle description is less clear in some senses than problems of biological classification, such as cyst morphology, because the fùndamental unit, the particle, does not have a phylogenetic relationship with others in its group (Pankhurst, 1979). The previously describeci exarnple of the classification of coal is of interest here, as coal is a heterogenous organic substance

' "One could argue that there is little value in describing cysts when their taxonomic identities are not known (Le. which taxa produced them). We disagree. Clearly, an important goal is to eventually determine the taxonomic affinities of the morphotypes. However, even if researchers only refer to numbered morphotypes at this stage, cysts cm still be used as powerfùl markers of environmental change, as well as other scientific endeavours. For exarnple, if cyst morphotypes cm be described in surface sediment calibration or training sets (see Charles & Smol, 1994, for a description of how these calibration sets and transfer fimctions are developed), and cyst morphotypes can be related to limnological variables of interest, then these data can be used to infer past changes in lake development (e.g. acidification, eutrophication, climatic change, etc.)." (Duff et al., 1995, P-11) 56 which is classified not-withstanding its complex structure and composition, and in spite of

the fact that there is considerable overlap of coal constitutents in coal specimens, both

rnicroscopic and macroscopic. Not only do the constituent parts or macerals CO-occur,but

they also intergrade into one another (Stach et a1.J 975). The solution for coal, in part, has

been to adopt physical measures to delineate coal classes. The problem of combustion

particle classification seems to lie somewhere in between that of chrysophyte cysts and coal:

the particles themselves, like cysts, are quite distinctive in many cases, but the relationship

of the particle to the parent material is indirect. This is true because it is modulated by the

combustion process as well as by transport and deposition. However, it is less cornplex than

the problem of coal classification because we are addressing those particles in the range of

microscopy. Coal classification deals with micro- and macroscopic features; and because, to

some estent, the process of combustion itself serves to reduce cornples firel into smaller

particles of more homogeneous composition (Watt & Thorne, 1965).

3.4.1. The identification of functional categories for classification

Given that my interest in combustion particles is related to their potential use as

tracers of atmospheric transport and possible ecological effects, 1 chose to adopt an artificial classification that would recognize features related to particle composition, density and

aerodynamic behaviour. The specific particle properties 1emphasized are shape, structure,

opacity and colour. The objective in creating descriptive categories based on these

properties is to establish categones which adequately contain the range of particle types observed, so that few empty categories occur, and so that almost al1 particles can be grouped

into them. This means that the categories used need to be comparable from site to site, but 57 sensitive to variation in the composition of the particle rain at the site. In some cases, this means maintaining a working category for new particle types until their status becomes clear. In this sense, the process of determination of the categories and the categones themselves could be considered an indicator of particle population variabiiity.

The term "shape" refers to the esternal geometric shape of the particle inferred fiom the two-dimensional image of the particle viewed through the microscope, coupled with depth of field adjustments- to determine the relief of the particle. Shape is an important feature of particles undergoing transport and deposition: as aerodynarnic behaviour is dependent on shape, as well as size (DallaValle, 1948). Shape (as weI1 as size) influence particle drag, which in turn afTect the distance a particle will travel and its fa11 speed (Hamilton, 1954; Robins, 1954; Timbrell, 1954). As noted above, there is an extensive literature addressing particle shape analysis, particularly in the contest of sedimentation (Kmmbein & Pettijohn, 1938; Whalley, 1990).

There are two primary shape-based categories that 1 use as the first step in discriminating particle types: spheroidal and non-spheroidai shapes. "Shape" has been used as a key diagnostic feature for combustion particles in some cases. For example, sphericity alone, or in combination with other features, has been used to identi@ carbonaceous particles (Griffin & Goldberg, 1979, 198 1; Renberg & Wik, 1985; Rose,

199 1). Shape characteristics may offer evidence of the process of combustion, fuel type or environmental processing. For example, wood charcoal (Plate 1) fiequently appears in sediment in the fom of lath-shaped particles with a width to length ratio of 13, a characteristic that has been used for identification (Griffin & Goldberg, 1979). Non- 58 spheroidal particles may be regular, with angular corners, like Iath-shaped or blocky rectangular charcoai; or irregular, with fiactal-like margins. In generai, spheroidal particles have been found to be associated with fossil fuel combustion, particularly coal

(Plate 2) and oil (Plate 3). However, as noted in Chapter 2, and above, wood combustion may also give rise to spheroidal particles (Patterson et al., 1987; Hueglin et al., 1997).

Recognizing that particle diarneter alone will not necessarily give an indication of relative buoyancy unless something is known of the probable density of the particle, I included sub-categories related to composition. One of these is structure, which is used to describe features. which may influence both the surface and the internal order of the particle on a scale that can be detected rnicroscopically. Ifthe structural feature affects the internal appearance. internal particle heterogeneity results in uneven transmission of light in non-opaque or rnixed opaque-non-opaque particles (for example, Plate 4, Figure 12); while similar types of particles, lacking internal variation, appear uniform. If surface homogeneity is affected, identifiable features may appear in profile with transmitted Iight or on the surface, as seen with reflected light. Sometimes the particle structure is a skeIeton, for example a lacy biomass particle (Plate 1, Figure IG), or fuel oil sphere (Plate

3, Figure 4). Structure is a useful criterion for classification purposes because it can contain clues to the nature of the fuel bumed, the type of combustion process involved and the conditions of operation. It is an important feature from the functional viewpoint of understanding transport phenornena, because as the paper by Patterson et al. (1987) points out, while the specific gravity of charcoal may range from 1.4 to 1.7, as a result of porosity of structure, the apparent specific gravity may actually be 0.3 to 0.6. Clearly this 59 has implications for the buoyancy of charcoal in air and in water, which in turn will affect its ability to be transported. Similarly lacy or hollow carbonaceous spheres, termed cenospheres (Fisher et al., 1978), or glassy silicate spheres with gas and small spheres within them, are likely to be less dense than their solid counterparts, an important difference when it comes to distance travelled.

Sphencal particles with structure, whether estemal (surficial) or intemal, are defined as "cornples particles" for purposes of this study (for example, Plate 2, Figures 3,

4. and 22). Similarly, solid particles Iacking distinguishing structure or ornarnentation are defined as "simple particles" (for example, the tiny glass spheres surrounding the central particle in Plate 2, Figure 5, also in Figure 6). Esternal structural elements may include small spheres, knobs due to condensation of various kinds of flume, crystals due to reactions of chemicals on the particle surface or by adhesion of crystals in the process of emission. Interna1 structures may include small spheres, crystals, gas bubbles, and water droplets. They may also include partitions related to giant hexagonaI carbon rings (see

Plate 3, Figure 4; shown, enlarged, in Appendix 2 ).

The characteristic of opacity refers to the capacity of the particle to transmit light under the light microscope when set up for polarized liglit, and is further refined as follows: particles which appear opaque in both plane polarized light and with crossed polars are defined as isotropic and are classed as truly opaque (McCrone & Delly, 1973).

However, particles which appear opaque with plane polarized light, but transmit Iight 60 when the polars are crossed, are defined as anisotropics and are classed as non-opaque particles (McCrone & Delly, 1973). Opacity is a significant physical property that can offer direct evidence of chemical composition as well as of combustion characteristics.

Colour is a complex property that can bear a direct relationship to particle composition and formation, and may in itself be diagnostic. The term is used here in the relative sense, as an aid to identification, because determinative or spectrophotometric study is beyond the scope of the present work. With polarized light, some combustion particles display a range of colour effects in a single particle when the relative position of the polarizing filters changes. Usually amorphous materials such as glasses and carbonaceoiis materials. are isotropic, transmitting light when the polars are parallel. and sliowing darkness or extinction of the light transmission, when the orientation of the polars is crossed. Isotropy is also a property of crystals in the cubic system. In minerals, birefringence is defined as the difference between refractive indices, an optical property which is due to relationsliips between crystallographic axes, and is a property of anisotropic particles (Hallimond, 1953). In combustion particles, anisotropic colour effects, or birefringence, may be due to strain induced by physical forces in the abrupt heating and cooling of glassy substances (Holland & Preston, 1937, 1938). In the case of organic substances that are apparently arnorphous and opaque, anisotropic effects

-- -- Strain birefringence is classified as anisotropy by McCrone & Delly, (1973) Vol. 1' p. 278; but petrographers generally restrict the use of the term "anisotropy" to describe crystalline materials, defining amorphous materials as intrinsically isotropic. The question as to how to define the colour shifl seen in some materials with the rotation of polarized light remains open. In the case of crystallin~inaterials, anisotropy may be appropriate, but the case with respect to amorplious materials is unclear. 61 discernibf e with crossed polars have been attnbuted to the ordering of polynuclear aromatic hydrocarbons to create "liquid crystais" (Lewis & Singer, 1988). An analogy cm be drawn with optical properties of coals: lignites to biturninous coais may be anisotropic, but more highly ordered, highIy condensed anthracite coals are not. The other mechanism by which anisotropic particles apparently may be created is the accumulation of a coating of anisotropic material on the surface of a particle, usually in the process of ernission, such as iron oxide coatings on smelter particles (McCrone & Delly, 1973). Technically, birefnngence is the difference between the minimum and maximum index of refraction of an anisotrûpic material (McCrone & Delly, 1973).

Specific examples are discussed in the Results section of this chapter and in

Appendis 3.4. While colour has been observed to be a variable property of combustion particles in general (Hamilton & Jarvis- 1963; McCrone & Delly, 1973), relatively few attempts have been made to develop a systematic ~Iassificationusing colour as a property

(see for example Cheng et al., 1976). However Griffin & Goldberg (1979) did use particle colour as a characteristic to sort combustion particles in environmental samples. In other fields of particle description, colour is considered to be an informative characteristic, for example, indicating composition and useful for tracing sedimentary units (Blatt, 1982). In sedimentary rocks, red, brown and yellow generally indicate femc oxide cernent

(hematite); while gray-black indicates fiee carbon as organic matter (Blatt, 1982).

For purposes of a standard for comparative purposes in this thesis, 1 have adopted two strategies to code the colours of the particles using independent colour scales, for those particles illustrated where colour is a critical feature. Opaque particles are coded 62 using the ~unsell@Soi1 Colour Charts (1994). In this system, hue, value and chroma are

given ratings. Hue represents the spectral colour and is denoted by a letter for each colour: R for red, YR for yellow-red, and Y for yellow. Value represents the depth of colour, where a score of O equates to white and a score of 10 to black. Chroma represents intensity and ranges from a score of O for neutral gray to 20 for the most brilliant intensity of colour. The soi1 charts do not exceed a score of 8 for chroma, however. For non- opaque matenal, 1 have taken the Michel-Lévy Birefringence Chart, first published in

Paris in 1888 (A. Michel-Lévy & A. Lacroix, Les Mineraux des Roches), and reproduced in McCrone & DelIy (1973), as a basis for colour coding. This chart interrelates thickness, birefringence (the difference between the refractive indices of an anisotropic substance) and retardation (the interference colours seen with crossed polars), to identify substances, 1am using it as a means of readinç standard coordinates for specific colours.

This use of the Chart for colour coding, as a colour standard, does not refer to thickness or birefringence. These colour standards define comrnon descriptive terms for coIour, which are included to assist the reader, recognizing that black and white reproduction may necessitate a range of colour references. In the text, where a coIour designation is critical, the appropriate co1our descriptive term is given, followed by a code for the colour. Thereafter only the common descriptive term is given. The common colour terms used are cross-referenced to the Munsell Scale and Michel-Lévy codes in Table 3.1. TABLE 3.1. COLOUR CODES FOR COMBUSTION PARTICLE DESCRIPTION COMMON COLOUR TERM ~ichel-~évv~ Munsell sca1e@l0

black grayish to greenish black dark brownish black reddish-black reddish-brown orange-brown brown dark red brilliant red brilliant red-orange

bright yellow O pm, 910nm

Iight brown-yellow 50 pm, 306 nm blue-violet O ym, 1 128 nm indigo white

Michel-Lévy, A., 1888. Birefringence Chart in: A. Michel-Lévy & A. Lacroix, Les Mineraus des Roches), Paris, reprinted in McCrone & Delly, 1973. 'O ~unsell@Soi1 Colour Charts, 1994. (Revised edition). TABLE 3.1. (CONTINUED)

COLOUR CODES FOR COMBUSTION PARTICLE DESCFUPTION

COMMON COLOUR TERM Michel-Lévy Munsell cale@

white O Fm, 359 nm

translucent white 35 Fm, 259 nrn

rnilhy white ciear no code no code 3.5. Particle features indicative of combustion processes

1have observed a number of particle features associated with combustion

particles, some apparently resulting from the chemical transformations inherent in the

burning process and some as a result of high temperature physical processes. The features that I found reference to in the literature and observed in the combustion reference samples, either singly or, more usually, in combination are as follows:

1) sphericity

2) interna1 air bubbIes

3) surficial craters resuIting from broken bubbles

4) plasticization or melting of surfaces

5) rounding of edges

6) swelling (particularly true of coals)

7) porosity or vesicularity

8) reticulation

9) opacity

10) cornplex structure associated with interna1 or external spheres

1 1) crystalline features, either single crystals within, piercing the surface or appended to the surface of spheres; or a crystalline mass; or surficial crystalline striae

12) charring, meming blackening and fragmentation along structural planes

13) sooting, meaning accretion of black carbonaceous films over a surface, particularly when the particle is biological

14) acifonn or aciculate carbonaceous spheroids or masses TABLE 3.2. SIGNIFICANCE OF COMBUSTION PARTICLE FEATURES IN

INTERPRETATION OF ENVIRONMENTAL PARTICLE RECORDS IN

RELATION TO TRANSPORT, DEPOSITION AND POSSIBLE EFFECTS

Feature Significance

shape - relates to origin (fuel and process)

- may also relate to transportabilityhuoyancy i-e.

aerodynamics

- may provide dues to transport processes involved

structure - relates to fuel and process

- may also relate to transportabilityh~~oyancyi.e.

aerodynamics opacity - relates to cl-iemical composition, structure and fuel

- rnay indicate cornpleteness of combustion colour - relates to chernical composition and structure s ize - relates to fuel and process

- may also relate to transportability/buoyancy i.e.

aerodynamics 15) anisotropy due to strain or form

16) sintered particles

17) agglomerated particIes

Based on the features presented by combustion particles listed above, and selection of key features according to the following criteria for significance (see surnmary in Table 3.2 below), combustion and other particles were observed in reference and environmental samples, and various approaches to categorizat ion were explored.

3.6. Results of the Combustion Particle Study

This investigation of features for the identification of combustion particles using light microscopy, and the observation of combustion reference materials and environmental combustion particles extracted frorn pond and lake sediments, resulted in the following:

1) A photographie reference set to aid in identification and classification,

consisting of several hundred photographs of combustion particle specimens from

known sources, fiels, burners and environmental sarnples, of which the general

forms are presented in Plates I to 11, which follow.

II) Development of a proposal for a detailed synoptic key" that describes the

range of particles observed, induded as Appendix 3.1.

" Note: This term "synoptic key" is used in the sense defined by Pankhurst (1979); to present a detailed description of the combustion particle classification. It is functional, structural, morphological and artificial, in nature and is intended as an aid to paleolimnological work using light microscopy. It is not intended to be organic, genetic, phylogenetic or biological in content or structure. 68 III) A functional, artiticial classification for use in documenting combustion

particle occurrence in lake and pond sedirnent for purposes of pdeolimnological

investigation, presented below in the form of a simplified graphical diagnostic

key, presented in Figure 3. l and descriptive text, included as Appendix 3.4.

IV) Application of the functional categories to environmental sarnples and an

exploration of the potential for increasing the sensitivity of the approach in case

studies.

These four elements serve to present the results of my observations of combustion particles in reference materials or "howns", and in environmental sarnples or

'~unknowns";and of my functional classification of these particles for purposes of describing combustion particles, as well as for documenting combustion particle records in sediments from arctic Iake and pond sediments.

3.7.1. Results Part 1: Photographie Atlas of Combustion Particles for

Palcoecological Studies

Section 1 of the Atlas presents a description in text and photographs of combustion particles resulting fiom the combustion of wood, coal, oil and mixed waste.

In Section 2, combustion particles found in lake and pond sediments are similarly described from Self Pond and Kirk Lake, Alert, Ellesmere Island; Horseshoe Pond, Cape

Herschel, Ellesmere Island; Hawk Lake, Keewatin; and Dry Pond, Raised Beach Pond and Pond 5, Belcher Islands, Hudson Bay. 69 3.7.2. Atlas Section 1. Combustion Particle Types in Relation to Fuels and Burners

3.7.2. (a) Wood combustion particles

PLATE 1

As illustrated in Plate 1, Figures 1 to 16, wood combustion can produce a wide

range of particle types, including rectangular (lath or blocky) (see centre of Plate 1,

Figures 4 to 6,9 and 10, and 12 and Ij), irregular (see mate 1, Figures 14 and 1S), angular (see centre of Plate 1. Figure 1 to 3,or rounded (Plate 1, Figure 1 to 3) shapes. The shapes of the sub-units formed in combustion are determined in part by the inherent structure of the wood. As can be seen in Plate 1, Figures 1 and 4, angular as well as rectangular shapes result from the burning away of more flammable rnaterial along edges of fragments. and within fragments where high temperature has caused shrinking, charring and subsequent fracturing along structural planes. For example, in Plate 1,

Figure 4, the central diagonal fragment displays greater charring and fissunng from the centre of the photograph to the top right, parallel to the grain, while below the centre the same fragment is less charred, and the planes that have open fissures above are still masked by partially charred lighter brown material below. A range of coIours and degrees of opacity are present, depending on the thickness of the fragment, the completeness of combustion and the by-products present. Plate 1, Figures I to 3 and 4 to 6 show a range of materials present in charcoal and ash from wood buming. Each of the photographs in these two sequences is taken under different lighting to emphasize the range of colours present. Figures 1 and 4 were taken with plane polarized light; Figures 2 and 3, and 5 and

6, were taken with slightly uncrossed polars. The presence of anisotropic matter is due in 70 part to the presence of minerals in the woody tissues, and partly as a result of anisotropic organic components, such as resin (see reddish rounded particle at centre of Figure 2) or other birefringent macromolecules. Figures 3 and 6 are reproduced in black and white, to draw attention to the bright (anisotropic) components, which appear as bright points of light. Combustion may be complete or incomplete, depending on the buming conditions, particularly the availability of osygen. Incomplete combustion of wood in a low oxygen atmosphere (under reducing conditions) leads to the production of charcoal, whereas larger amounts of oxygen increase the completeness of combustion, resulting in greater ash production and less charcoal. Charring, or carbonization, produces a dark brown or black material that ofien preserves some features of the original biomass, such as woody vesse1 walls, which are composed of more resistant molecules containing less volatile material.

In the case of wildfire, it is not only the woody tissues that are subject to combustion: al1 organisms caught in the fire may yield charred remains. Indeed, commercial charring operations have traditionally utilized wood and bones to produce a range of organic substances, including bone black, and other pigments (McCrone &

Delly, 1973). The particles produced may range in size from very tiny spheres, less than 1 pm in diameter, to giant lath shaped particles 100 pm or more in length, depending on burning conditions. 1 have observed charcoal particles as large as 150 Pm in length in sediment samples. Depending on the original bioinass structure, the charred fragments rnay preserve elements of plant structure, such as vesseli, early and late wood ce11 walls, or resin ducts. 71 PLATE 1 FIGURES 1 TO 16. WOOD COMBUSTION PARTICLES FIGURES 1 to 6, and 12 to 15 are of samples from a domestic fireplace, burning mixed hardwood and soffwood. Figures 7 to 1 1 are fiom open burning in temperate mixed deciduous and coniferous forest. Figures 3,6,7, and 12 are rendered in black and white, for emphasis. Al1 other figures are colour reproduction. Scale bars are shown beneath each Figure. For Figures 1 to 6, and 14 to 16, the scale bar represents 50 Pm. For Figures 7 to 13, the scale bar represents 30 Pm. FIGURES 1 to 3 show the sarnple, first with plane polarized light, second with slightly uncrossed polars, and third with crossed polars and a slight change in focus. Note the presence of the lighter material that appears brown (Munsell 7SYR 5/6)to yellow (Munsell7SYR 7/6) in Figure 1. In Figure 2 the light areas appear white (Munsell 8 2.5Y/1) to yellow (Munsell7.5YR 7/6). The centre of the image contains spheroidal resin-like body that changes from reddish-brown (10R 2.5/1) in plane polarized light to dark red (Munsell 10R Y6). Some of the bright, anisotropic light-coloured rnaterial appears to be calcite.

Note the various fünctional categones of wood charcoal that appear: FIGURES 1 to 3 - angular charcoal; FIGURES 4 to 6,7 and 8, 14 and 15 - blocky and rectangular; FIGURE 9, 10, 12 and 13 - lath-shaped charcoal; and FIGURE 16 - lacy charcoal Figure 1 Figure 2 Figure 3

Figure 4 Figure 5 - Figure 6 -

- Figure 7 Figure 8 Figure 9 Figure 10 Figure 1I

- - Figure 12 Figure 13 Figure 14 Figure 15 Figure 16 3.7.2. (b) Coal combustion particles

PLATE 2

As referred to previously, coaI fly ashes have been studied intensively, and since

Watt & Thorne (1969) pointed out the importance of understanding coaI fly ash composition at the level of particle composition, as opposed to that of bulk sarnples, many studies have investigated these particles using microscopy (see for exarnple Cheng et al., 1976; Griffin & Goldberg, 1979; Fisher et al., 1976, 19786).

Coal combustion particles can take a variety of shapes, sizes and colours as shown in Plate 2 (see Figures 1 2, 8 and 14). These photographs show random sarnples of coal fly ash from coal buming power generation stations in Ontario, al1 of which are burning

Western Canadian lignite coaIs containing 0.4% sulphur. The variety of particles present are due to a combination of factors related to the composition of the parent coal, particularly its minera1 content. and the conditions at which it was fired. The particle shapes range from true splieres (for example, Plate 2' Figure 6 and 23, to spheroids

(Plate 2, Figure 5 and 1O), to irregular particles (Plate 2, Figure 1 (top centre) and 14), with a lacy or lurnpy appearance. Some particles are transparent (Plate 2, Figures 3 and

4), some translucent (Plate 2, Figure 22) and others are opaque (Plate 2, Figure 6), or a mix of opaque and non-opaque material (Plate 2, Figure 20). The colours present range from milky white to bright white, to pale or lemon yellow, orange, orange red, brown, gray, and black (Plate 2). This range of colours is similar to that found by Cheng et al.

(1976) in their studies of Amencan coals. In terms of structural complexity, a range of forms is present. 1 have found simple spheres (Plate 2, Figure 5) without ornarnent or 73 internai structure; complex spheres with intemal features such as small spheres (Plate 2,

Figure 3 and 4), gas or liquid filled vacuoles (Plate 2, Figure 11, 12 and 13, note cross with crossed polars in 12 and 13), or crystals; or external adhesions of crystds (Plate 2,

Figure 9) or spheres (Plate 2, Figure 10). Sometimes the crystals penetrate the skin of the sphere, forming so-called "quench" crystals (Natusch et al., 1974). "Needle" encrusted spheres are also seen. Coal combustion particles also appear irregularly shaped with lacy or porous voids (Plate 2, Figure 14), and as agglomerated particles, festooned with coalesced matter, including small spheres, or crystals (Plate 2, Figure 20). These forms are in agreement with descriptions in the literature, although terminology is variable, and the terms are not used consisteiitly- For example, Fisher et al. (1 976) coined the tern

'~pleurosphere"to describe "cloudy" particles containing many tiny spheres. Clearly this term was intended to apply to glassy spheres, and this is the sense in which it is used here, although not al1 usage has been consistent. These pleurospheres are perhaps the most spectacular of the large particles seen in the coal fly ash, as illustrated for example by the

Iarge particle to right of the field of view in Plate 2, Figure 7.

One of the interesting particle features which 1 have found in some fly ashes that I have not yet seen repo~tedis the presence of anisotropic spheres that appear opaque in plane polarized light, but present a vivid red or orange colour with crossed polars as shown in Plate 2, Figures 17 and 18. Note the change in appearance of the small sphere in the centre of the cluster in each photograph. 74 PLATE 2 FIGURES 1 TO 22. COAL COMBUSTION FLY ASHES AI1 photographs are in colour, except where black and white (b&w) reproduction is indicated. Where colour is considered to be particularly significant, a descriptive colour term is given. These colour terms are defined in TABLE 3.1 according to standard colour references. ALI photographs in this pIate are taken in plane polarized light (PP), unless Iight conditions are othenvise indicated (i.e. crossed polarized light (AxP), or with polarizers removed (PO))-The size of the scale bars is as indicated. FIGURE 1 Lingan Power Station coal fiy ash composite sarnple. Particle colours include: black (opaque), white and yeliow. Scale bar is 30 pm FIGURE 2 Belowes Coal Fly Ash. Scale bar is 50 pm Particle colours include white, clear, black and gray FIGURE 3 Atikokan Coal F1y Ash. Particle colours clear, pale yellow and gray. Scale bar is 50 pm FIGURE 4 Same view as FIGURE 3. ( AxP). ScaIe bar is 50 pm FIGURE 5 Atikokan Coal Fly Ash. Scale bar is 20 Fm FIGURE 6 Thunder Bay Cod Fly Ash. Scale bar is 15 pm FIGURE 7 Thunder Bay Coal Fly Ash. Scale bar is 20 pm FIGURE 8 Atikokan Coal Fly Ash. Scale bar is 30 prn FIGURE 9 Thunder Bay Coal FIy Ash. Scale bar is 20 pn FIGUE 10 Nanticoke Coal FIy AskScale bar is 1 S pm FIGURE 1 1 Thunder Bay Coat Fly Asli. Scale bar is 12 pm FIGURE 12 Thunder Bay Coal Fly Asli. Scale bar is 12 pm (AsP) FIGURE 13 Thunder Bay Coal Fly Ash. Scale bar is 12 pm (AxP) FIGURE 14 Nanticoke Coal Fly Ash ScaIe bar is 25 pm FIGURE 15 Atikokan Coal FIy Ash. Scale bar is 10 Pm FIGURE 16 Atikokan Coal Fly Ash. Same view as FIGURE 15. Scale bar is 10 pm (AsP) FWRE 17-30 Nanticoke Coal FIy Ash Scale bar is 30 pm FIGURE 17 Same as FIGURE Z 8 (AxP) FIGURE 18 Same as FIGURE 17 (PP) FIGURE 19 Tiny spheres (AxP) FIGURE 20 (AxP) FIGURE 2 1 Thunder Bay Coal Fly Ash. Scale bar is 10 pin FIGURE 22 Atikokan Coal Fly Ash. Scale bar is 35 pm (AxP) Figure 3 Figure 4

Figure 1 Figure 2

Figure 9 Figure 7 - Figure8 -

- - - - Figure 17 Figure 18 Figure 19 Figure 20 Figure 2 1 Figure 22 3.7.2. (c) Oil combustion partictes

PLATE 3

Particles resulting from oil combustion also show a range of particle types, as

illustrated in Plate 3, Figures 1 and 2. Particles may be irregular (Plate 3, Figure 1O), ovate (Plate 3, Figure 3)' roughly spheroidal (Plate 3, Figure 6) or tnte spheres (Plate 3,

Figure 5). depending on the forces acting to produce them. Spheres rnay be lacy (Plate 3,

Figure 6) or l~ollow(Plate 3, Figure 5). The particles may be opaque (Plate 3, Figure 3) or transparent (Plate 3, Figure 7), or mised translucent/opaque (Plate 3, Figure 8 and 9).

Lacy spheres with regular skeletons (Plate 3, Figure 4), aciculate spheres, sometimes with dendritic needles, (Plate 3, Figure 13) may also appear. The particle colours I observed in the reference materials include black to dark brown, lighter shades of brown. golden yellow, du11 orange and white. In addition to these colours, greenish and reddish brown particles are reported in the literature (Cheng et al., 1976). Cornparison of views with plane polarized light (Plate 3 Figure 1) and with slightly uncrossed polars (Plate 3 Figure

2) indicates that much of the material present is anisotropic. With crossed polars, some oil fly ash particles show intense birefringence, changing either frorn black to brownish- orange, or showing blazing white areas.

Many of these particles appear black with a bluish cast in transmitted light. With oblique top light, some particles appear reddish-orange. 76 PLATE 3 FIGURES 1 TO 13 OIL COMBUSTION PARTICLES FIGURES 1 to 13. Colour images of oil combustion particles from the Lennox Power Plant. Al1 photographs are in colo- except where black and white (b&w) reproduction is indicated. Where colour is considered to be particuIarIy significant, a descriptive colour term is given. These colour terms are defined in TABLE 3.1 according to standard colour references, Al1 photographs in this plate are taken in plane polarized light (PP), unless Iight conditions are otherwise indicated (Le. crossed polarized light (AxP), or with polarizers removed (PO)). The size of the scale bars is as indicated. FIGURE 1 Colours include black, reddish-black, white, orange brown and gold. ScaIe bar is 50 pn FIGURE 2 Same view as Figure 1. Scale bar is 50 pm AxP FIGURE 3 Scale bar is 50 pm FIGURE 4 ScaIe bar is 100 Fm PO FIGURE 5 Scale bar is 50 pm FIGURE 6. Scale bar is 50 pm FIGURE 7 Scale bar is 20 pm .4xP FIGURE 8 Scale bar is 20 pm FIGURE 9 Same particle as FIGURE 8 Scale bar is 20 Fm AxP FIGURE 10 Scale bar is 20 Pm AxP FIGURE 1 1. Scale bar is 20 prn FIGURE 12. Same particle as FIGURE 1 1 Scale bar is 20 pn AxP FIGURE 13 Scale bar is 20 pm Figure 1 Figure 2

Figure 3

Figure 4 Figure 5

Figure 6 - Figure 7 - Figure 8 - Figure 9 -

Figure 10 - Figure 1 I - Figure 12 - Figure 13 - 3.7.2. (d) Incinerator fly ash

PLATE 4

While waste consigned to incineration is not usually considered to be a fuel type. it is an important source of particulate emissions to the environment (Vandegrift et al.,

197 1) and since open burning and, recently, incinerator facilities are used for garbage disposa1 in the north, I decided to include this particle source. As Plate 4 shows, incineration can produce many of the particle types previously seen, including pleurospheres (Plate 4, Figures 1 and 3, and 12) and agglomerated spheroids, encrusted with tiny spheres and carbonaceous matter (PIate 4, Figures 3,4, and 5). The previously referenced images are three views of the sarne particle: with crossed poIars, the particle becomes light in colour and surface detail beconies visible as shown in Figures 4 and 5.

ParticIes tend to become sintered together in the process of combustion and emission, as in the composite particles shown in PIate 4, Figures 6a and 6b; 7 and 8; 10 and Il. The heterogeneity of these compound particles is cIearly sl-iown in the views using crossed polars (see Figures 4. 6b and 1 1). In addition to the spheroidal particle types, biomass fragments (Plate 4, Figure 9, lower lei?); and irregular opaque (Plate 4, Figure 1O and 1 1, lower centre) and non-opaque particles (Plate 4, Figure 6a and 6b, lower centre) also appear. Particle diversity is very high, in large measure due to the diversity of materials from commercial and domestic tvaste disposal, which are bumed. 78 PLATE 4 FIGURES 1 TU 12, INCINERATOR ELY ASH COMBUSTION PARTICLES FIGURES 1 - 12. These photographs are taken of a ~c~rone@reference slide of incinerator fly ash. Note the diverse shapes and composition of the particles present, AI1 photographs are in colour, except where black and white (b&w) reproduction is indicated. Where colour is considered to be particularly sipificant, a descriptive colour term is given. These colour tems are defined in TABLE 3.1 according to standard colour references. AH photographs in this plate are taken in plane polarized light (PP), with crossed polarized light (AxP), or with the polarizers removed (PO). The size of the scaIe bars is as indicated, FIGURE 1. Transparent spheroid with vacuoles. Note cratering on surface. Scde bar is 40 Pm. b&w FIGURE 2 Sarne as FIGURE 1 (abolie), but in colour. Faint blue tinge to cratering. Scale bar is 40 Pm. FIGURES 3 - 5. Show the same spheroidal particle in different lighting: FIGURE 3 Scale bar is 40 p.PP FIGURE 4 Scale bar is 40 Fm. AxP FIGURE 5 Scale bar is 40 Pm. AxP, b&w (with increased contrast) FIGURES 6 a and 6 b Show the same spheroidal particle in different iighting: FIGURE 6 a Scale bar is 20 Fm. PP FIGURE 6 b Scale bar is 40 Pm. AsP FIGURE 7 - 9. Show the sarne non-spheroidal particle in different lighting: FIGURE 7 Scale bar is 40 Pm. PP FIGURE 8 Scale bar is 40 Fm. AxP FIGURE 9 Scale bar is 40 Pm. AxP, with longer focal length FIGURE 10 and 1 1 Show the sarne composite particle in different lighting: FIGURE 10 Scale bar is 50 prn- PP FIGURE 1 1 Scale bar is 50 Pm. AxP FIGURE 12 ScaIe bar is 35 pm. PP Figure 1

Figure 3 - Figure 4 -

Figure 7 Figure 8 Figure 9

- Figure 10 - Figure 12 3.7.2. (e) Stationary combustion particle sources in the Arctic

PLATE 5

The category of stationary sources is of particular interest in the Arctic, as cornrnunities are few and often far apart. There is no central power grid in the North.

There is little industrial activity, and the development-related activity which does occur is dependent on local power generating and often, in the case of larger establishments, central heating and power are provided to the community, or base as a whole, through a utilador system. This means that combustion point sources are found in remote areas. In addition to these central facilities, there are rnany private dwellings using oil space heaters or stoves, with mixd buming of garbage taking place as well. Plate 5 contains a selection of particles from three different types of point sources in the Arctic: Figures 1 to

15 were taken from a staff house chimney vent at what was formerly the Isachsen weather stationi2on Axe1 Heilberg Island, to the west of Ellesmere Island. The staff house was heated with an oil stove, and is an example of domestic combustion. Figures 16 to 20 corne from the Isachsen power plant and are esamples of diesel generator combustion particles from an older facility. Figures 2 1 to 25 corne from the snow surface near the central power plant at Alert, at the north end of Ellesmere Island. and are an exarnple of diesel generator particles from an operational facility.

Again the particles found display many forms, mainly highly irregular in outline.

The particles associated with the staff house and domestic burning were complex in shape, and of generally mixed composition, containing both opaque carbonaceous

" The Isachsen Weather Station has been abandoned for more than 15 years. 80 material as well as non-opaque and anisotropic materials. There is some similarity between partides found in these samples from oil combustion, and those found in the oil combustion samples of Plate 3. The power plant samples tended to contain spheroidal black particles as well as a variety of catalyst particles, some still quite angular (see

Figure 25), but others somewhat rounded by the combustion process (Figure 21, for example). Lath shaped particles (Figure 24) and bright, birefringent glassy rods, visible with polarized light and crossed polars, are also present. 8 1 PLATE 5 FIGURES 1 TO 25. STATIONARY SOURCES OF COMBUSTION PARTICLES FIGURES 1 - 25. The particles included here are from northern oïl, diesel and mixed combustion. Al1 photographs are in colour, except where black and white (b&w) reproduction is indicated. Where colour is considered to be particularly significant, a descriptive colour term is given. These colour terms are defined in TABLE 3.1 according to standard colour references. AI1 photographs in this plate are taken in plane polarized light (PP), with crossed polarized light (AxP), or with the polarizers removed (PO).The size of the scale bars is as indicated. FIGURE 1 - 15 are from the Isachsen Weather Station staff house. FIGURE 1 Reddish-black. Scale bar is 50 pm. FIGURE 2 Same particle as FIGURE 1Some anisotropy. Scale bar is 50 pm AsP FIGURE 3 Scale bar is 20 pm AxP FIGURE 4 Scale bar is 30 pm AxP FIGURE 5 Sarne particle as FIGURE 4 Scale bar is 30 pm AxP FIGURE 6 Bright yellow with white. Scale bar is 40 pm AxP FIGURE 7 Scale bar is 20 pm AxP FIGURE 8 Scale bar is 20 Fm FIGURE 9 Scale bar is 20 pm FIGURE 10 Scale bar is 20 pm AxP FIGURE 1 1 Scale bar is 12 pm FIGURE 12 Same particle as FIGURE 1 1. Scale bar is 12 pm- AxP FIGURE 13 Scale bar is 20 prn FIGURE 14 Brilliant red-orange. Same particle as FIGURE 1 1. Scale bar is 20 pm AsP FIGURE 15 Scale bar is 20 Fm FIGURE 16 - 20 are from the Isachsen power plant FIGURE 16 Scale bar is 5 pn FIGURE 17 Scaie bar is 10 pm FIGURE 18 Sarne particle as FIGURE 17. Brilliant red-orange. Scale bar is 10 pm FIGURE 19 Scale bar is 12 pm FIGURE 20 Scale bar is IO Fm FIGURE 2 1 to 25 are from the Alert power plant FIGURE 2 1 Scale bar is 40 pm FIGURE 22a Scale bar is 25 pm FIGURE 22b Same particle as FIGURE 22a. Scale bar is 25 pm. AxP FIGURE 23 Scale bar is 45 pm FIGURE 24 Scale bar is 40 pm FIGURE 25 Scale bar is 30 pm -,.,-; ,::u*-;-.-i.- ". , :.. - . __.. . .. _ . -_ .. .>.-If ;:-.", , &"' -'' .--.-.--. .-.~ -&--=Y.:??- -., . .- .. : ..:&...y..- -.Ti,.. ci:. . ,.. ' . :: *..',:,,:.*d.- ,:. :-L .

.,: , ;:?.*a- -.. - - .-..A\.*.. -:."! .. ,.*c!;.2G-:,.- 4 < ...... - .. -1 -. 'I - . . 1.:;...:4<;;- .+;<-.<':,*- , .. . , - Figure 1 Figure 2 Figure 3 Figure 4 Figure 5

- Figure 6 Figure 7 Figure 8 Figure 9 Figure 10

- - Figure 11 Figure 12 Figure 13 Figure 14 Figure 15

- - - - Figure 16 Figure 17 Figure 18 Figure 19 Figure 20

- Figure 22 - Figure 2 1 Figure 23 Figure 24 Figure 25 3.7.2. (f) Mobile combustion sources in the Arctic

PLATE 6

When 1 began this study, 1collected many combustion particle samples, including samples from various vehicles in use at northern locations. This was done in part to increase my understanding of local sources, as weII as to provide reference material from actua1 local sources to assist in interpretation of environmental samples.

Plate G contains photographs of particles from a number of mobile fossil fuel combustion engines. PIate 6, Figures 9 and 10 present views of automobile exhaust, first with plane polarized light, then with slightly uncrossed polars. Al1 other images in this plate are ofsamples taken from diesel-powered equiprnent: Plate 6, Figures 1 to 10 are of samples taken from a CF10 Flex Track bulldozer, Plate 6, Figure 1 1 is from a cat tractor,

Plate 6? Figures 12 to 14 are from a diesel-powered Russian helicopter, and Plate 6,

Figure 15 is from a diesel-powered Russian truck. The features which best describe these particles are, for the most part, the absence of a clearly defined shape. although rounded particles can be seen in Plate 6, Figures 3 and 4, and 5 and 6; a wide range of possible sizes; the presence of composite particIes formed by aggregation or agglomeration; cornplex particle outlines; and a range of colours including a dark brownish black (Plate

6, Figures 12: 13 and Ij), grayish to greenish black (Plate 6, Figures 9 and IO), and reddish brown with a purplish hue. Also sorne brilliant red to orange particles (Plate 6,

Figure 1 and 2), and some true anisotropic materials (Plate 6, Figure 5 and 6), are seen.

As in the case of stationary diesel combustion, catalyst particles are also present (for exampIe, Figure 14). There is relatively little literature addressing these types of 83 emissions as particles, partly because they are composites of the accumulation of a great many very small particles. The best source of information related to these particles is

McCrone & Delly (1973).

While the emissions of diesel vehides have been studied estensively in connection with urban air pollution in cities, less information is available about the emission of particles to the environment during diesel or gasoline engine operation in the

North. For purposes of this study, 1 have assumed that the biggest differences would be associated tvith fuel conditioning for operation in coIder temperatures, and therefore it is possible that some differences in particle production observed from equipment in operation in the North may esist. when cornpared with descriptions of emissions from similar equipment in use in the South. 84 PLATE 6 FIGURES 1 TO 15. MOBILE COMBUSTION PARTICLES

FIGURES I - 15. These images present a variety of particles taken from vehicles and heavy mobile equipment at sites in the Arctic unless othenvise indicated. Al1 photographs are in colour, except where black and white (b&w) reproduction is indicated. Where colour is considered to be particularly significant, a descriptive colour term is given. These colour terrns are defined in TABLE 3.2 according to standard colour references. Al1 photographs in this plate are taken in plane polarized Iight (PP), with crossed polarized light (AxP), or with the polarizers removed (PO). The size of the scale bars is as indicated.

FIGURE 1 CF IO Flex Track diesel. Scale bar is 20 pm FIGURE 2 CF 10 Flex Track diesel. Same particle as FIGURE 1. Brilliant red-orange. Scale bar is 20 pm- AxP FIGURE 3 CF 10 Fiex Track dieseI. Scale bar is 20 Fm FIGURE 4 CF 10 €les Track diesel. Sarne particle as FlGURE 3. Scale bar is 30 Pm- AxP FIGURE 5 CF 10 Flex Track diesel. Scale bar is 20 pm FIGURE 6 CF 10 Flex Track diesel. Same particle as FIGURE 5. Scale bar is 20 Fm- AsP FIGURE 7 CF 10 Flex Track diesel. Scale bar is 20 pm FIGURE 8 CF 10 Flex Track diesel. Scale bar is 20 pm

FIGURE 9 Auto eshaust ~c~rone@reference slide. Scale bar is 40 Fm. FIGURE 10 Auto eshaust ~c~rone@reference slide. Same as FIGURE 9. Scale bar is 40 Fm. AsP

FIGURE 1 1 Cat Tractor diesel. Scale bar is 30 pm FIGURE 12 Russian helicopter diesel. Scale bar is 30 Fm FIGURE 13 Riissian helicopter diesel. Scale bar is 30 pm FIGURE 14 Russian helicopter diesel. Scale bar is 40 pm FIGURE 15 Russian truck diese1. Scale bar is 30 pm - Figure 3 Figure 4

- Figure 1

- Figure 5 Figure 6

- Figure 2 Figure 7 Figure 8

- - Figure 9 Figure 10 Figure 11

Figure 12 Figure 13 Figure 14 Figure 15 3.7.3. Atlas Section 2. A Survey of Combustion Particles from Lake and Pond

Sediments at Selected Sites in the Arctic

This section of Chapter 3 presents selected particles observed in sediments from the study sites: Self Pond and Kirk Lake, at Alert, northem Ellesmere Island, ~unavut'~;

Horseshoe Pond, Cape Herschel, Ellesmere Island, Nunavut; Hawk Lake, located to the north of Chesterfield Inlet, Keewatin, Nunavut; and three sites on the Belcher Islands, at the confluence of Hudson and James Bay, Nunavut: Dry Pond, Pond 5 and Raised Beach

Pond. The locations of these sites are shown in Figure 1.1. Additional site information is given in Table 3.3. Descriptions of the sites and sarnpling procedures are given in

Chapters 4, 5 and 6. Processing is described above, in Appendix 3.2, and in the chapters that follow, with particular details given in this chapter as needed.

3.7.3. (a) Alert Sites: Self Pond and Kirk Lake

PLATES 7 AND 8

The combustion particles occurring here consist of primarily two types: splieroidal opaque. lacy particles as show for esarnple in Plate 7, Figure 5 and 6, and 14, 15 and 16; and glassy shards and rods, some of which are birefnngent, as illustrated in Plate 7,

Figure 1 and 2, as well as in the background behind the opaque particles in Plate 7,

Figures 5 and 6, and 13. In addition to the lacy splieroids and glassy shards, mixed opaquehon-opaque particles (Plate 7, Figures 3 and IO), and opaque solid spheres (Plate

7, Figure 1 1 and 12, 13, 17 and 18) are also observed.

'' Nunavut was created in 1999 through division of the Noahwest Territories TABLE 3.3. SUMMARY OF SITE LOCATION DATA

Site Latitude Area (ha) Proximity to Elevation

Longitude development (m ASL)*

Self Pond 82O25'N 37 -9h SSE 120 - 180

63OOO'W of CFB Alert

Kirk Lake 8Z027'N 1O0 -1 1 km SW (60

63O49'W of CFB Alert

Horseshoe 78O3 7'N - 4

Pond*" 79O4 1'W

Hawk ~ake' 63"38-N 24.3 40kmNof

-- Pond 5*** 56O35-N -1 -2km NNW of -4.5

79O 15'W Sanikiluaq

Raised SG034'N -1 -3hNWof -70

Beach Pond*** 7g0 16.W Sanikiluaq

Dry Pond*** 5do33'N

79O12'W Sanikiluaq

*The National Atlas of Canada, 5" Edition. Energy, Mines and Resources, Canada. Canada Relief, 1986; unless othenvise indicated ** M.S.V. Douglas, Ph.D. Thesis, 1994 *** M.S.V. Douglas, pers. Commun-, 1999 '~uir,et al., 1995 Note: Lockhart (1 995, p.634)gives Longitude of Hawk Lake as 90' 40' 87 PLATE 7 ENVIROMMENTAL COMBUSTION PARTICILES I FIGURES 1 TO 18.

FIGURES 1 - 18. Al1 particles in Plate 7 corne from sediments frorn Self Pond, Alert, Ellesmere Island, Nunavut with the exception of FIGURES 4, 7, and 10 which are oil combustion reference particles, and FIGURE 14 which is from snow near AIert. Al1 photographs are in colour, except where black and white (b&w) reproduction is indicated. Where colour is considered to be particularly sipnificant, a descriptive colour term is given. These colour terms are defined in TABLE 3. l according to standard colour references. Al1 photographs in this plate are taken in plane polarized light (PP), with crossed polarized light (AxP), or with the polarizers removed (PO). The size of the scale bars is as indicated.

FIGURE 1 Scale bar is 40 pm FIGURE 2 This view is the same as FIGURE 1. Scale bar is 40 Fm. AxP. Note pair of particles in lower lefi corner. Also blue spheroid left of centre, which is anisotropic. and appears white in FIGURE 3. FIGUE 3 Scale bar is 30 pm FIGURE 4 Oil combustion reference particle. Scale bar is 50 Fm FIGURE 4 Scale bar is 40 pin FIGURE 5 Scale bar is 40 pm FIGURE 6 Particle is the same as FIGURE 5. Scale bar is 50 Fm FIGURE 7 Oil combustion reference particle. Scale bar is 20 Fm FIGURE 8 Scale bar is 40 pm FIGURE 9 Scale bar is 30 pm FIGURE 10 Oil combustion reference particle. Scale bar is IO pm FIGURE 1 1 Scale bar is 10 prn FIGURE 12 Particle is the same as FIGURE 1 1. Scale bar is 40 Fm. AsP and top light. FIGURE 13 Scale bar is 20 pm FIGURE 14 Combustion particle from snow sample. Scale bar is 35 pm FIGURE 15 Scale bar is 10 pm FIGURE 16 Scale bar is 10 Pm FIGURE 17 Scale bar is 1O prn FIGURE 18 Scale bar is 10 pm Figure 3

Figure 1 Figure 2

- Figure 4

Figure 5 Figure 6 Figure 7 Figure 8

- Figure 9 Figure 10 Figure 11 Figure 12 Figure 13

- - - - Figure 14 Figure 15 Figure 16 Figure 17 Figure 18 PLATE 8 ENVIRONMENTAL COMBUSTION PARTICLES 11 FIGURES 1 TO 25. FIGURES 1 - 25. Al1 particles shown are from lake and pond sediments at study sites at Alert, and at Cape Herschel, Elfesmere Island, and Hawk Lake, Keewatin, Nunavut. Al1 photographs are in colour, escept where black and white (b&w) reproduction is indicated. Where colour is considered to be particularly significant, a descriptive colour term is given. These colour terms are defined in TAE3LE 3.1 according to standard colour references. Al1 photographs in this plate are taken in plane polarized light (PP), with crossed polarized light (AxP), or with the polarizers removed (PO). The size of the scale bars is as indicated.

FIGURES 1 to 5 are from Kirk Lake, at Alert FIGURE 1 Charcoal lath. Scale bar is 50 pm FIGURE 2 Charcoal lath. Scale bar is 50 pm FIGURE 3 Charcoal lath. Scale bar is 50 pm FIGURE 4 Non-opaque spheroid. Scale bar is 20 pm FIGURE 5 Opaque spheroid. Scale bar is 10 pm FIGURES 6 to 17 are from Horseshoe Pond, Cape Herschel, Ellesmere IsIand. FIGURE 6 Opaque spheroid. Scale bar is 10 pm FIGURE 7 Opaque spheroid. Scale bar is 10 pm FIGURE 8 Opaque non-spheroid. Scale bar is 10 Fm FIGURE 9 Non-opaque spheroid. Scale bar is 10 pm FIGURE 10 Particle is the same as FIGURE 9. Scale bar is 10 pm AxP FIGURE 11 Charcoal lath. Scale bar is 10 prn FIGURE 12 Charcoal blocky. Scale bar is 25 pm FIGURE 13 Charcoal blocky. Scale bar is 15 pn FIGURE 14 Charcoal blocky. Scale bar is 15 pm FIGURE 15 Particle is the same as FIGURE 14. ScaIe bar is 15 prn AxP FIGURE 16 Charcoal blocky. Scale bar is 15 pm FIGURE 17 Charcoal blocky- Scale bar is 15 pm FIGURES 18 to 25 are from Hawk Lake, Keewatin FIGURE 18 Opaque spheroid. Scale bar is 3 pm FIGURE 19 Opaque spheroid. Scale bar is 10 pm FIGURE 20 Opaque Iacy spheroid. Scale bar is 5 pm FIGURE 21 Non-opaque spheroid. Scale bar is 30 pm FIGURE 22 Non-opaque spheroid. Scale bar is 20 pm FIGURE 23 Non-opaque spheroid. Scale bar is 20 pm FIGURE 24 Non-opaque spheroid Scale bar is 10 pm FIGURE 25 Particle is the sarne as FIGURE 24. Scale bar is 10 pm AxP - - Figure 1 Figure 2 Figure 3 Figure 4 Figure 5

- - - - - Figure 6 Figure 7 Figure 8 Figure 9 Figure 10

- - - - - Figure t 1 Figure 12 Figure 13 Figure 14 Figure 15

- - - - - Figure 16 Figure 17 Figure 18 Figure 19 Figure 20

- - - - - Figure 2 1 Figure 22 Figure 23 Figure 24 Figure 25 89 Some of the spheroidal particles that appear solid and opaque manifest deep brown to black hues with slightly uncrossed polars and a low level of oblique top Iighting

(Figure 11 and 12). Very rarely, extremely smaIl(4 prn diameter) solid opaque spheres are seen that display brilliant red, orange, blue or purple with slightly uncrossed polars.

At Kirk Lake onIy, large (>50 pm) lath shaped charcoal fragments containing fibrous structures were found (Plate 8, Figures 1 to 3). These partides were evidently from wood combustion. In addition, a vesicular, gIassy spheroidal particle type was found. This charcoal record appears to be anomalous, and is most readily explained by human activity locally. As discussed in greater detail in Chapter 4, the Kirk Lake site is used as a recreational location and has a barbecue on the beach.

While large (150 pm in Iength or diameter) particles were observed in the AIert samples, the diameter of most of the spheroidal particles was much less, ranging from the lirnit of resolution to -1 2 Fm. The glassy shards were 2 to 20 pm (outside dimension), and the glassy rods rangsd from 2 to 8 pn~in Iengtli, with more observed in the smailer sizes.

3.7.3. (b) Horseshoe Pond

PLATE 8

The distribution and abundance of combustion particles in the sediments from Horseshoe

Pond, Cape Herschel, and Hawk Lake, Keewatin are discussed in detail in Chapter

5.found it interesting to observe that the combustion particle types and Levels present in the Horseshoe Pond sarnples differed from those at Alert as well, however. Opaque 90 spheroidal particles were still recorded, but translucent/transparent pleurosphere-type

particles occurred (Plate 8, Figures 9 and IO), as did a greater variety of shapes of

biomass particles. Lath shaped charcoal particles were present (Plate 8, Figure 1 1. 14 and

15), and blocky to lacy shaped particles also appeared. However glassy shards and rods were not recorded here.

3.7.3. (c) Hawk Lake, Keewatin

PLATE 8 AND 9

The combustion particles found in the sediments from the Hatvk Lake sarnples were much more diverse than those from the Alert or Cape Herschel samples were. SoIid opaque spheres occurred (see Plate 8, Figure 18 and 19 for esample). as did lacy spheres

(Plate 8. Figure 20). Hollow glassy spheres were present (Plate 8, Figure 21, and Figures

21 and 25). sometimes ornamented with tiny adhesions, or marker grains (Plate 8, Figure

31). Pleurospheres, with tiny spheres within (Figure 23). as well as inclusions of carbon and otlier material (Plate 8. Figure 23) also appeared. The most striking combustion particles were those associatecl with biomass combustion: estremely large (>IO0 pm in

Length) lath shaped particles (Plate 9 Figure 1); very large (>50 pm) lacy charcoal particles (Figures 2,4, 5 and 6),and blocky to angular biomass particles. 9 1 PLATE 9 ENVIRONMENTAL COMBUSTION PARTICLES 111 FIGURES 1 TO 23. FIGURES 1 - 23. Al1 particles in Plate 9 come from lake and pond sediments from sites at Hawk Lake, Keewatin, and the Belcher Islands, Hudson Bay, Nunavut. Al1 photographs are in colour, except where black and white (b&w) reproduction is indicated. Where colour is considered to be particularly significant, a descriptive colour term is given. These colour terms are defined in TABLE 3.1 according to standard colour references. ALI photographs in this plate are taken in plane polarized light (PP), with crossed polarized light (AxP), or with the polarizers removed (PO). The size of the scale bars is as indicated.

FIGURES 1 to 6 are from Hawk Lake, Keewatin FIGURE 1 Charcoal - lath. Scale bar is 25 pm FIGURE 2 Charcoal - lacy. Scale bar is 40 pm FIGURE 3 Charcoal - angular Scale bar is 20 pm FIGURE 4 Charcoal - lacy Scale bar is 45 Fm FIGURE 5 Charcoal - lacy Scale bar is 20 Fm FIGURE 6 Charcoal - lacy. Scale bar is 25 pm FIGURES 7 to 23 are from the Belcher Islands sites: Dry Pond (7 & 8), Raised Beach Pond (9 - 20) and Pond 5 (21-23) FIGURE 7 Opaque spheroid. Dry Pond. Scale bar is 15 prn FIGURE 8 Charcoal - lath. Dry Pond Scale bar is 20 pm FIGURE 9 Opaque spheroid. Raised Beach Pond Scale bar is 15 pm FIGURE 1O Particle is the sarne as FIGURE 9 Scale bar is 15 pm AxP FIGURE 1 1 Non-opaque spheroid. Scale bar is 15 pm FIGURE 12 Opaque lacy spheroid. Scale bar is 10 pm FIGURE 13 Non-opaque spheroid. Scale bar is 25 pm FIGURE 14 Opaque spheroid. Raised Beach Pond Scale bar is 15 pm FIGURE 15 Non-opaque spheroid. Scale bar is 15 pm FIGURE 16 Particle is the same as FIGURE 15 Scale bar is 15 pm AxP FIGURE 17 Charcoal - lath. Scale bar is 20 pm FIGURE I 8 Charcoal - lath. Scale bar is 25 pm FIGURE 19 Charcoal - lath. Scale bar is 30 pm FIGURE 20 Charcoal Scale bar is 20 pm FIGURE 21 Pond 5 Scale bar is 5 pn FIGURE 22 Pond 5 Scale bar is 5 pm FIGURE 23 Particle is the sarne as FIGURE 22. Scale bar is 5 pm AxP - 1 Figure 2 Figure Figure 3 Figure 4

Figure 5 Figure 6 Figure 7 Figure 8

- - - Figure 9 Figure 10 Figure 1 1 Figure 12 Figure 13

- - - - Figure 14 Figure 15 Figure 16 Figure 17 Figure 18

Figure 19 Figure 20 Figure 21 Figure 22 Figure 23 92 3-7.3. (d) The Belcher Islands: Dry Pond, Pond 5 and Raised Beach Pond

PLATES 9 AND 10

Combustion particles found in the Belcher Island sarnples included opaque spheres without features (Plate 9, Figure 14; Plate 10 Figure 1). and opaque spheres with surface and interna1 features (Plate 10 Figure 3), and opaque spheroidal lacy or reticulated particles (Plate 9, Figure 12). A varïety of translucent/transparent pleurosphere type particles with tiny spheres (Plate 10 Figure 9), gas vacuoles (Plate 9 Figure 1 1) and other spheroidal inclusions (Plate 9, Figures 13, 15 and 16, and 22 and 23; and PIate 10,

Figures 7 and 10) were found. Agglomerated spheroids were recorded as well (see Plate

10, Figures 6 and 8). Colours of the opaque spheroidal particles ranged from black (Plate

9, Figures 7 and 14; Plate 10, Figure 1) to dark brown hues (see Plate 9, Figure 5 and 10; and also the srnallest sphere in Plate 10, Figures 5 and 6); to brown (Plate 10, Figure 15); and to yellow-brown (Plate 9, Figure 22). As well, particles appearing gray (see Plate 9,

Figure 15). milky white (note medium sized particle in Plate 10, Figure 6) and clear (Plate

10, Figure 10) were seen among the glassy spheroids. An interesting occurrence was that of reddish-brown, opaque particles. which appeared brilliant red or orange, with slightly uncrossed polarized light? illustrated under both light conditions in Plate 10 Figures 11 and 12; and 13 and 14.

Biomass combustion particles were present in a range of shapes and structures, including laths (Plate 9, Figures 8, 17, 1 8, 19; and Plate 10, Figures 16 (larper particle),

18, and 21); lacy irregular shaped particles (Plate 10, Figure 22,23 and 25); and angular irregular particles (Plate 10, Figure 24). Blocky rectangular charcoal (Plate 10, Figure 16 93 PLATE 10 ENVIRONMENTAL COMBUSTION PARTICLES IV FIGURES 1 TO 25. FIGURES 1 - 25. Al1 particles in Plate 10 come from sediments from Pond 5 in the Belcher Islands, Hudson Bay, Nunavut. ALI photographs are in colour, except where black and white (b&w) reproduction is indicated. Where colour is considered to be particularly significant, a descriptive colour terni is given. These colour terrns are defined in TABLE 3.1 according to standard colour references. Al1 photographs in this plate are taken in plane polarized light (PP), with crossed polarized light (AxP), or with the polarizers rernoved (PO)- The size of the scale bars is as indicated. FIGURE 1 Opaque spheroid. Scale bar is 12 pm FIGURE 2 Particle is the same as FIGURE 1. ScaIe bar is 12 Fm FIGURE 3 Opaque spheroid. Scale bar is 10 pm FIGURE 4 Opaque spheroid. Scale bar is 15 pm FIGURE 5 Opaque spheroid. Scale bar is 16 Fm FIGURE G Cluster of opaque and non-opaque spheroids. ScaIe bar is 10 pm FIGURE 7 Non-opaque spheroids. Scale bar is 8 prn FIGURE 8 Non-opaque spheroids. Scale bar is 9 prn FIGURE 9 Non-opaque spheroid. Scale bar is 10 pm b&w FIGURE 10 Non-opaque spheroid. Scale bar is 10 Fm FIGURE 1 1 Non-opaque spheroid. Scale bar is IO pm FIGURE 12 Particle is the same as FIGURE 1 1. Note brilliant red. Scale bar is 10 prn AxP FIGURE 13 Non-opaque spheroid. Scale bar is 3 pm FIGURE 14 Particle is the same as FIGURE 1 1. Note brilliant red Scale bar is 3 prn AsP FIGURE 15 Opaque spheroid. Scale bar is 5 pm FIGURE 16 Charcoal. Scale bar is 10 pm FIGURE 17 Charcoal. ScaIe bar is 20 pm FIGURE 18 Charcoal. Scale bar is 15 pm FIGURE 19 Charcoal - incomplete combustion. Scale bar is 15 pm FIGURE 20 Particle is the same as FIGURE 19. Note brilliant red-orange Scale bar is 15 Fm AxP FIGURE 21 Charcoal lath Scaie bar is 40 pm FIGURE 22 Charcoal - lacy Scale bar is 20 prn FIGURE 23 Charcoal - lacy Scale bar is 20 pm FIGURE 24 Charcoal - angular Scale bar is 20 Fm FIGURE 25 Charcoal - Iacy Scale bar is 20 pm - - Figure 1 Figure 2 Figure 3 Figure 4 Figure 5

Figure 6 Figure 7 Figure 8 Figure 9 Figure 10

Figure 11 Figure 12 Figure 13 Figure 14 Figure 15

- - - Figure 16 Figure 17 Figure 18 Figure 19 Figure 20

- Figure 2 1 Figure 22 Figure 23 Figure 24 Figure 25 94 (smaller particle), and charcoal with some degree of rounding were also recorded (Plate 9,

Figure 20 and Plate 10, Figure 17). The colours associated with the biomass particles

varied from black (Plate 9, Figure 19; and Plate 10, Figures 16, 17,22,23, 24), to dark

brownish-black (Plate 9, Figure 1 S;and Plate IO, Figure 18), and to lighter shades of gray-

brown (Plate 9, Figure 17) and brown (Plate 10, Figure 2 1). One of the more vivid

particle colours associated with biomass is shown here in a reddish-brown fragment of arnorphous texture that blazed bright yellow and orange-brown with slightly uncrossed polars (Plate 10. Figures 19 and 20). This appears to be a conifer fragment, and the colour response may be due to incomplete combustion of resinous constituents.

3.8. Results Part II: Devcloprnent of an Artificial Classification for Combustion

Particles in Sediment

Afier surveying the range of combustion particles that occurred in reference materials. 1began to document the particles found in my inventory of subsamples from lake and pond sediment cores. Initially, as descnbed above, 1 focused on those particles described as black and spherical, which have been the subject of other paleolimnological studies (for example, Wik & Renberg, 1985; Rose, 1990). However, as I increased the number of reference samples, types and observational techniques, 1 recognized a number of distinct types, many of which were reported in fuel combustion studies. In my first attempt at a classification, 1 used the categories set out in Table 3.4 below. For a description of the combustion particle categories used in this table, see Appendix 3.4. 95 TABLE 3.3. INITIAL DESCRIPTIVE CATEGORIES OF COMBUSTION PARTICLES USED FOR DEVELOPMENT OF THE ARTIFICIAL SYNOPTIC CLASSIFICATION PRESENTED IN APPENDIX 3.1.

A. Combustion particle categories defined by B. Divisions and groups shape, defined opacity, and structure by shape and structure

Division 1: sphencal combustion particles 1. transparent simple spherical combustion particles 1.O. simple sphencal 2. translucent simple sphencal combustion particles combustion particles 3. opaque simple sphencal combustion particles

4. transparent comples spherical combustion 2.0. comples spherical particles combustion particles 5. translucent complex spherical combustion particles 6. opaque cornplex spherical combustion particles

7. charred biomass Division II: non-spherical combustion particles 3.0 biomass

8. generic non-spherical opaque combustion 4.0. generic combustion particles particles

5. other classes of related particles

(See Appendix 3.5) 96 At the same time as attempting to categorize combustion particles in general, 1 worked on enurnerating spherical black combustion particles in the lake and pond sediments. As an increasing number of sarnples from a variety of sites were investigated,

I became dissatisfied with this approach and began to take note of other types of particles on an individual basis. When more individuals of a given type were seen, and a threshold of three or more particles of a distinct type were seen, a decision was made to create a discrete category. This was also an iterative process, at times requiring revisiting of samples, and inclusion of particles previously exciuded. Ultirnately in excess of30 discrete particle types were recognized and described using shape, opacity, structure and colour, as criteria for classification. These categories are presented in the form of the synoptic key in Appendis 3.1.

3.9. Rcsults Part III: Constructing a Functional Key to Combustion Particles for

P~ileolimnoIogicaiuse"

The synoptic key, however, was not entirely satisfactory, as relatively few individuals were found in a number of the classes created, implying that the categories were perhaps too narrow. Also, this key was designed to present a broad range of combustion particle types, emphasizing distinctions between categories. For paleoecoIogica1 studies, a fimctional classification was needed that would enable me to constmct categories on the basis of similarities among the particle characteristics relevant

l4 Note that while the application discussed here refers pnmarily to combustion particles in sediment, 1have also applied these, and other methods, to snow and glacier ice sarnples from the Arctic. 97 to the questions of ultimate interest: propensity for long-range transport; probability of a

common source, and implications for environmental consequences.

After a number of trials, the following working categories were identified from the ~Iassificationin Appendix 3.1, and a simplified version of the artificiaI key was developed (see Table 3.5). The categories presented in Table 3 -5 were then used for purposes of inventory of particle distribution and abundance in environmental sediment samples. As discussed above, particle size was also assessed for selected sites, and then recorded for each of the descriptive categories.

It should be noted that, for each category in Table 3.5, there are a number of possible types, for esarnple the type "non-opaque spheroidal simple" includes a range of coloured as well as clear and white spheres, and the "non-opaque spheroidal complex" category contains spheres with crystal inclusions, tiny spheres, surface adhesions. The common denominator is the grouping of types sharing features that have an identified basis for association. as the aim is to create groups on the basis of affinities, in tems of possible origin and morphologica1 sirnilarities. Thus. the common threads Iinking the types of spherical particles in the non-opaque cornples category described are composition, meaning non-carbonaceous components of heterogeneous fuels; and high temperature combustion in a burner perrnitting rapid transit and emission of particles, thus explaining the comples interna1 and external structural features.

It is also important to note that the classification must be able to cope with a measure of arnbiguity in particle identity, yet produce categories of "like" particIes that TABLE 3.5. COMBUSTION PARTICLE CATEGORIES DEFINED FOR THE PURPOSE OF MAKING PARTICLE COUNTS FROM SAMPLES OF LAKE AND POND SEDIMENT Category of combustion particle Abbreviation or symbol used 1. opaque spheroidal simple Spheroidal combustion particle, black SPBK SpheroidaI combustion particle, black to red with SPBK(AxP) crossed polars (AxP)

2. opaque spheroidal comples (cenosphere) Csph

3. non-opaque spheroidal simple particle, non-black NBKSP Translucent coloured TI Yellow Y1 Brown Br Red RD White W

4. non-opaque spheroidal comples combustion particle Psph Pleurosphere

5. non-spheroidal combustion particle black. or dark red NSPBK or "diesel-type" NSPBK(R)

6. charcoal chtot Angular chang Blocky chbloc Lath chlath Arnorphous cham Rounded chmd

7. combustion opaque Cmop combustion opaque arnorphous Cmarnop combustion opaque, angular Cmanop combustion - rounded Cmoprn combustion - rounded arnorphous Cmamm combustion - lacy CmIacy combustion - amorphous Cmarnor 8. combustion amorphous non-opaque Cmamnop 9. combustion amorphous mis opaquehon-opaque Cmammix 99 can be inventoried to build combustion records arnenable to interpretation in the context of environmental change-

Working from the list of "divisions and groups" on the right in Table 3 -4 and the

"categories" list on the lefi in Table 3.5, the following selection of basic typest5was made:

spheroidal combustion particles

simple spherical combustion particles

complex spherical combustion particles

non-spheroidal combustion particles

biomass

generic combustion particles

In order to move from this descriptive List of possible categories of combustion particles to a simplified key, the hierarchy of particle characteristics was re-ordered, with the following priority : shape. opacity, structure and CO lour. Each of these continuous variables was then divided into dichotomous pairs resulting in the following structure

1. shape

spheroidal

non-spheroidal

2. opaciîy

opaque

non-opaque

'' For a detailed description, see Appendix 3.4. structure

amorpho us

ordered

4. colour

none - black

present - clear to dark gray or brown, including full spectrurn

By overlaying the characteristics of the particles observed, as listed in the right column of

TabIe 3.4, on this simple tree skeleton, and using graphic symbols, the functional key wliich follows was created (see Figure 3.1). FIGURE 3.1. Simplified functional key to particle categories for paleolimnological applications. First level ofcategories is defined by shape: particles are either spheroidal or non-spheroidal. The second level is defined by structure: for spheroidal particles the structure is either simple or cornples; and for non-spheroidal particles, the structure either indicates structure related to biornass or no such structure is detected, in which case the particle is classed as a generic combustion particle. For spheroidal particles, the third level is defined by opacity. For biomass combustion, the third level is shape and porosity. For generic combustion, the third level is defined by opacity. Details of a more complex synoptic key with additional levels of classification are provided in Appendix 3.1. SIMPLIFIED FWNCTIONAL KEY 1 SPHEROIDAL 1

1 SIMPLE 1

NON-SPHEROIDAL .

1 OPAQUE NON-OPAQUE MIXED 102 3.10. Results Part IV: Applications of the functional categories to environmental

samples and an exploration of the potential of the approach

This classification is applied to the problem of spatial and temporal distribution of

combustion products in the arctic environment at selected sites along a north-south

transect from Alert, Ellesmere Island, to the Belcher Islands, Northwest Temtones (now

Nunavut), in the Canadian Eastern Arctic in Chapters 4,s and 6. In Chapter 7 a synthesis

of the results from the study sites are presented in summary form: groups of particle

types. temied '-super groups". are plotted according to the geographic location of the

study sites to give a preliminary indication of the spatial distribution of these "super groups'?.

In addition to this work documenting the occurrence of combustion particles in lake and pond sediments, 1 have also observed combustion particles in snow from the surface of the permanent ice pack on Arctic Ocean, from seasonal snow surfaces on land and from ice cores fi-om glacier ice. While this work is on-going and is not the pnmary contribution of this thesis, 1 have included representative examples in section 3.7 Results

Part 1. above, for esample the particles depicted in Plate 5 Figures 21 to 25; and the particle in Plate 7, Figure 14, which also appears as Plate 1 1, Figure 2. 1 have presented results of this work at the Fifth International Conference on Carbonaceous Particles in the

Atmosphere, Berkeley, California, 1994. 1 have also reported aspects of the study design and of the application of combustion particle research to snow and ice samples in Musk

0x(Doubleday, 1992). 103 3.1 1. Discussion: The Application of the Functional CIassification and the

Esamination of Combustion Particles from Lake and Pond Sediments

PLATE 11

The next step in the development of the functional categories was to increase the sensitivity w-ithin each category in order to begin to recognize individual particles and to develop their potential as tracers of specific transport routes and events. As McCrone &

Delly (1973) have pointed out, the sensitivity of optical microscopy is such that a trained analyst is capable of detecting the presence of unique particles present in samples at concentrations as low as one picogram per gram. The classic work of McCrone & Delly

(1 973) deals with al1 particles. a much vaster particle universe, than combustion particles alone. To pursue the astronomical analogy further, if we think of combustion particles as but one of the many galaxies of particles wliich would be addressed in a "universal" particle classification. our task is immediately simplified if ive cm delin~itthis galasy of interest, usinç the criteria 1 have chosen to determine a particle's combustion origins. The problem of identification is now immediately reduced by several orders of magnitude. It cm be further sirnplified by choosing subsets: just as galaxies consist of solar systems, and these can be characterized by star magnitude and intensity, so too can assemblages of combustion products be thought of as heterogeneous systems of particles as distinct from one another as the stars, planets and cornets used to characterize astronomical assemblages. Just as we have the capacity to uniquely identify individual heavenly bodies as to type, so it is possible to assign combustion particles to categories.

While the prospect of finding single particles in sarnples at low levels of 1O4 occurrence is challenging when the sample is taken as a whole, it in fact becomes much

more manageable when that component of the sample which is of interest (i.e. combustion particles) is first selected, and then split into categories that are distinctive

and quickly recognized. It then becomes possible to begin to recognize affinities at the

level of individual particlesl as ilIustrated in Plate 1 1, and to a iesser extent in Plate 7.

Here, selected reference particles (some included in the preceding plates) and environmental correIates are presented showinç the degree to which correspondences cm be drawn at this stage of development of this approach. In Figures 1 to 1O of Plate 1 1, and Figures 3 to 10 of Plate 7' we see a range of particles grouped initially as complex opaque spheroids. Within tliis broad category?subgroups can be selected. For example, the particles in Plate 7' Figures 3 and 4. and Figures 5 and 6 (note these two photographs show the same particle witli different lighting) are lacy or porous opaque spheres with a greatest diameter of 25 to 30 pnl- Similarly the particles in Plate 1 1, Figures 1, 2, 3 (note,

Plate 1 1, Figure 3 shows the sarne particle as in Plate 7, Figure 3, with a slight adjustment of the n~icroscopesetup). 4 and 5 are al1 porous or lacy carbonaceous spheres, witli a greatest diameter of 25 to 30 Fm. Witliin this sub-grouping of opaque, spheroidal. lacy particles, however, even finer distinctions could be drawn if desired, on the basis of the degree of porosity. IO5 PLATE 11 ENVIRONMENTAL COMBUSTION PARTICLES V FIGURES 1 TO 25. FIGUEES 1 - 25. Plate 1 1 presents a selection of spheroidal particle types from lake and pond sediments and from various reference samples, as indicated below. This plate illustrates the discussion of Chapter 3. Al1 photographs are in colour3except where black and white (b&w) reproduction is indicated. Where colour is considered to be particularly significant, a descriptive coIour term is given. These colour terrns are defined in TABLE 3-1 according to standard colour references. Al1 photographs in this plate are taken in plane polarized light (PP), with crossed polarized Iight (AYP),or with the polarizers removed (PO). The size of the scale bars is as indicated. FIGURES 1 TO 10 ARE COMPLEX SPHEROIDS: OPAQUE FIGURE 1 Kirk Lake Opaque lacy spheroid Scale bar is 25 pm FIGURE 2 Alert Snow. Opaque lacy spheroid Scale bar is 30 pm FIGURE 3 Self Pond. Opaque lacy spheroid Scale bar is 30 pm FIGURE 4 Pond 5. Opaque spheroid Scale bar is 10 pm FIGURE 5 Hawk Lake. Opaque lacy spheroid Scale bar is 10 pm FIGURE 6 Pond 5. Opaque spheroid Scale bar is 10 prn FIGURE 7 Lennox Oïl Fly Ash. Opaque spheroid Scale bar is 25 pm AxP FIGURE 8 Pond 5. Opaque spheroid Scale bar is 10 Fm kuP FIGURE 9 Incinerator Fly Ash Opaque spheroid Scale bar is 40 pm AxP FIGURE 10 Thunder Bay Fly Ash. Opaque spheroid Scale bar is 12 pm FIGURES 11 TO 15 ARE SIMPLE SPHEROIDS: OPAQUE FIGURE 1 1 Raised Beach Pond. Opaque spheroid Scale bar is 15 pm FIGURE 12 Pond 3. Opaque spheroid Scale bar is 10 Fm FIGURE 13 Pond 5. Particle is the same as FIGURE 12. Note brilliant red. Scale bar is 10 pm AsP FIGURE 14 Nanticoke Coal Fly Ash. Scale bar is 10 pm FIGURE 15 Nanticoke Coal Fly Ash. Particle is the same as FIGURE 14. Note brilliant red. Scale bar is 10 pm FIGURES 16 TO 10 ARE COMPLEX SPHEROIDS: NON-OPAQUE FIGURE 16 Pond 5. Scale bar is 12 pm FIGURE 17 Atikokan Coal Fly Ash. Compare with FIGURE 16 (above). Scale bar is IO pm FIGURE 18 Raised Beach Pond. Pleurospliere (cornplex non-opaque spheroid) Scale bar is 25 pm FIGURE 19 Thunder Bay Fly Ash. Pleurosphere Scale bar is 35 p FIGURE 20 Thunder Bay Fly Ash. Particle is the sarne as FIGURE 19. Scale bar is 35 pm FIGURE 21 Atikokan Coal Fly Asli. ScaIe bar is 22 pm FIGURE 22 Pond 5. Scale bar is 20 prn FIGURE 23 Pond 5. Scale bar is 10 prn FIGURE 24 Catalyst particles. ~ccrone@Reference Slide. Scale bar is 20 prn FIGURE 25 Catalyst particles. ~ccrone"Reference Slide. Scale bar is 35 pm - - - Figure 1 Figure 2 Figure 3 Figure 4 Figure 5

- Figure 6 Figure 7 Figure 8 Figure 9 Figure 10

- - - - Figure 11 Figure 12 Figure 13 Figure 14 Figure 15

- - - Figure 16 Figure 17 Figure 18 Figure 19 Figure 20

- - - - Figure 21 Figure 22 Figure 23 Figure 24 Figure 25 The second sub-groupins that can be made easily in the complex opaque

spheroidal group is Figures 6 to IO of Plate 1 1. The subgroup contains complex, opaque

spheroidal particles, but here they are characterized by the presence of accreted material

on the surface, in the form of crystals, or tiny spheres (Le. externally complex opaque

spheroidal particles). The lesser degree of development of porous or lacy features in this

subgroup suggests a lower temperature origin for these particles in relation to the more

fully combusted and expanded lacy spheres in Figures 1 to 5. It is also important to take into consideration the possibility of heterogeneous composition, at which point the usefulness of colour characteristics can be emphasized. For example, in Plate 1 1, Figure

9. using transmitted as well as oblique top Iight with crossed polars. the particle appears mottled reddisli brown to dark brown. rather than a true black or brotvn-black, as is the case for particles in Figures 8 and 10, which are adjacent to it. This strongly suggests a non-carbonaceous composition for the particle in Figure 9, in which case it would be reasonable to anticipate that there rnay well be differences in particle density and origin, as well as transport behaviour and environmental effects. While the analysis of these differences in chemical composition and related considerations are outside the scope of the present study, the recognition that such differences can be detected signals the need to include factors related to composition in the development of this class. The presence of a faint Becke line in specimens viewed under polarized light, (as for exarnple, in Figures 7 and 8), is interesting: clearly tliere is some Iimited light transmission in these materials which are otherwise opaque. This is also a potentially usehl characteristic, as well as an issue for further study, as this phenornenon may be linked to the property of polynuclear 1O7 aromatic materials to develop Iiquid crystal complexes in the process of incomplete combustion as reported by Lewis & Singer (1 988).

The third group illustrated in Plate 1 1 is that of simple opaque spheroids, shown in Plate 1 1, Figures 11 to 15. This group of particles ranges between 1O and 15 pm in diarneter, although much smaIler particles (-1 pm) have been observed in some of rny environmental sarnples. In Figure 1 1, a typical opuque particle is shown: it is imperfectly spherical (hence spheroidal), true black (Munsell2,5/N) and isotropic. However, in the nest two pairs of figures (Figures 12 and 13, and Figures 14 and 15), a striking difference appears between the particle images with plane polarized light (Figures 12 and 14) and with slightly uncrossed polars (Figures 13 and 15). These particles display a form of anisotropy, changing in colour from a reddish-black (Munsell 1OR3.Y 1) to a dark red

(Munsell 10RY6) as in Figure 15, or to a brilliant red (Michel-Léw coordinates: O Pm,

470 nm) as in Figure 13.

The remainder of Plate 1 1 esplores variations among selected cornplss non- opaque spheroidal particles in polarized light that can also be further subdivided into two sub-groupings. The first sub-grouping includes glassy spheres with a mottled appearance shown in Plate 1 1, Figures 16 and 17 (note, particle diameters are 12 and 10 Pm, respectively), in plane polarized light. The variation in colour is due to inclusions of droplets of gas or liquid, or solid spheres, closely resembling those shown previously in

Plate 2, and in particular the largest spherical particle in the lower right quadrant of

Figure 7. In Figures 18. 19 and 20 (same particle shown with incompletely crossed and uncrossed polarizing filters), and 21 , esamples of somewhat larger spheres are given, also 108 in plane polarized light. Note that Figures 19 and 20 show the same particle with crossed polars and plane polarized light respectivdy. The particle in Figure 18 has a diarneter of

25 Fm, while that of Figures 19 and 20 is 35 Fm. The particle in Figure 2 1 is 33 pm in diarneter. These particles also contain inclusions of droplets (gaseous or liquid) and crystalline matter, Al1 three particles (show in Figure 18, Figure 19 and 20, and Figure

31) are transparent with tinges of light brocvn-yellow (Michel-Lévy coordinates: 50 Pm,

306 nm), blue-violet (Michel-Lévy coordinates: O Fm, 1 128 nm), indigo (Michel-Lévy coordinates: O Pm, 600 nm); gray (Michel-Lévy coordinates: O pm, 2 18 nm) and white

(Michel-Lé~ycoordinates: O Pm. 259 nm). Careful inspection of the outer edge of these particles reveals adhesions of tiny spheres that have become attached on emission. Plate

1 1, Figure 21 closely resembles Plate 1 1- Figure 20, with its "vacuoles" of gaseous or liqriid incIusions.

Figures 22 to 25 of Plate 1 1 are aIso non-opaque and comples spheroids, however they are quite different in overall appearance from those in Figures 16 to 2 1, being imperfect spheres, translucent rather than transparent, and showing a range of surface details from knobby encrustations (Plate Il, Figure 22, 23 and 25) to irregular reticulate ridges (Plate 1 1, Figure 24). In colour, these particles are also quite different, ranging from a translucent white (Michel-Lévy coordinates: 35 Pm, 259 nrn); to straw yellow

(Michel-Lévy coordinates: 35 Fm. 28 1 nm); to yellow-brown (Michel-Lévy coordinates:

50 Pm, 306 nm).

The description of the particIes sources (the reference materials, environmental sarnples, fuels and processes) from which the particles used in the groupings just made 1O9 were taken, are from the following sites: in the first "grouping" (Le- cornplex opaque

spheroids) presented above. the particles shown in Plate 1 1 , Figures 1 to 3 are from the

sites at Alert; those in Plate II, Figures 4,6 and 8 are from the Belchers; and the particle

in Plate 1 1, Figure 5 is from Hawk Lake in Keewatin. The particles from combustion

references in this group are Plate 11, Figure 7, oil-fired power generation (Lennox

Generating Station), Plate 1 1, Figure 9, incinerator fly ash (McCrone No. 79): and Plate

1 1. Figure 10, coal fly ash from Western Canadian lignite coal with a sulphur content of

0.4% (Thunder Bay Generating Station).

In the second group (Le. simple opaque spheroids), Plate 11, Figures 1 1, 12 and

13 corne from sites in the Belcher Islands, and Plate 1 1, Figures 14 and 15 are from coal

fly ash (Nanticoke Generating Station).

In the tliird group (i.e. comples non-opaque spheroid), Plate I 1, Figures 16, 18, 22

and 23, corne froni sites in the Belcher Islands; and Plate 1 1, Figures 17 and 2 1 show

particles from coal fly as11 from Western Canadian lignite coal witli a sulphur content of

0.4% (Atitkokan Generating Station). Figiires 19 and 20 are from coal fly as11 from

Western Canadian lignite coal with a sulphur content of 0.4% (Thunder Bay Generating

Station). Plate 1 1, Figures 24 and 25 are catalyst particles from a cat-cracker type diesel generating plant reference sIide (McCrone SI ide No. 76).

In developing this approach, 1 started witli the characteristics of as wide a range of particles associated with con~bustionas possible, and the particle record as it occurs in sediments, and asked "what features of combustion are most relevant to the question of sources, transport and contarninants?" By taking those features as a basis for establishing 110 categories for documenting combustion records in sediments, then recording the nurnber, and sizes of the particles that occur in each, I began to look for contrasting and complernentary patterns of occurrence which may point to cornmon or contrasting sources, pathways or effects.

Previous atternpts to find relationships between source areas and distributions of cliarcoal particIes in sediment, for exarnple, have met with varying degrees of success, usually greater for local tlian regional sources (see for example, Sugita et al., 1994). This has been attributed to atmospheric transport effects, including gravitational settling rates, as welI as particle shape and size effects resulting in non-linear decay with distance from source patterns (see Clark & Patterson, 1994). Better results have been obtained for spheroidal combustion particles (Rose & Juggins, 1996; Rose, 199 1). As discussed above, the data sets resulting from atmospheric research are generally more sophisticated and developed, but for the most part have dealt with particles a pni in diameter. With some relatively rare exceptions (noted in Chapter 2), atmosphenc studies rarely consider

-'coarse3 particles. Siniilarly, there is much less research directed to the study of Larger combustion particles in sediments (Clark et al.. 1994). Comples patterns of air mass movement have aIso been used to account for transport and deposition of combustion products. at a range of scales of distance frorn local to global (Garstang et al., 1994). It has been suggested that sources, emission factors, transport dynarnics and depositional behaviours would idealiy be known before sedimentary records can be interpreted (Clark et al., 1994), but these conditions seldom exist (Suman et al., 1994), posing very real constraints for modeling. In remote regions like the Arctic, we are unlikely to obtain data 111 on many aspects of the environment, simply because there habeen no data collection, and hence the value of paleolimnological proxies for understanding environmental change is high (Douglas & Smol, 1999).

There are a number of issues that arise in attempting to look at combustion products from a wide range of potential combustion sources: the first is identification of particles as combustion products, so that it is possible to recognize them as they occur in sediments in the environment. 1have approached this problem from the standpoint of

Iearning to identie combustion particles from reference samples, and from handbooks, an approach similar to that of learning to identiQ rocks and minerais, using hand sampIes. In some respects, however, the recognition of combustion products, as distinct from biological or mineralogical fragments, does not Iend itself as readily to a systematic approach. This is because the source materials, the Iiydrocarbons and cornplex organic macromolecules from which fuels corne, are interrelated geologically, biologically and ultimately chernically. in bot11 the pre- and post combustion States. Moreover, the rnorphological features used to distinguish particies are retated to the original fuel substance, to the type of burner, and to the process of combustion itself. For these reasons, although there are instances where distinctive particle katures are uniquely attributable to a particular fuef/burner combination (see McCrone & Delly, 1973), 1am not convinced that there are enough cases where this is true. Therefore, one cannot yet espect to be able to attribute al1 particles found individually in the sediment environment to a single unique fuel or source on a routine basis.

An alternative approach then, is to attempt to deal with the suite of combustion 112 particles comprising a sample, in a manner not unlike that of a Sherlockian crime

investigation, where each thread found at the murder scene is relevant, but in itself

insufficient to explain events. It seems appropriate to cal1 this a "forensic" strategy. In the

case of sediments from ponds and lakes in the Arctic in particular, this approach is

complicated by the possibility of taphonomic changes, meaning the changes that

combustion particles may have under gone in the process of transport and deposition, and

with the passage of time. Just as in the cases solved by the intrepid Holmes. the story

becomes much more difficult to make out when (to pursue the analogy) there are many

intervening events and lead-footed officiais have trampled the evidence. In the

sedimentary environment, combustion particles are potentially subject to a range of

events. such as leaching of minerals, volatilization of organic compounds such as lighter-

weight polynuclear aromatic hydrocarbons, or events causing mechanical and biological

degradation, such as ingestion by aquatic organisms. However. if it is possible to identie

similarities in distribution trends between categones of particles. it may be possible to

make robust inferences about their oriçins. One of the constraints of this approach is that

sedimentation rates in the Arctic are generally very low? and very high resolution

subsampling of the sediment core is necessary if such changes are to be recognized at a

fine temporal resolution.

In order to implement a "forensic?', or what might be thought of as a "guilt by association", approach to combustion particle study. wlde exmination and classification of every particle according to the criteria developed in this thesis is necessary, the further steps of description and absolute identification of every particle on a particle by particle 113 basis is not. Although further steps to achieve absolute identification may be possible

andor required in some cases, the combustion particle classification and the "forensic approach" described above provide a means of esploring the distribution of combustion particles in the environment and related associations of environmental factors. The classification is a means of describing adequately the relative composition of a suite of combustion particles recorded in a discrete sample, so that changes frorn site to site or from tirne period to tirne period, can be detected and compared. In short, the classification and inventory serve to promote a process of pattern expression and recognition, so that the distribution of combustion particles can then be compared with other trends in the environment. This approach also avoids the probiem of dependency on the laborious, espensive and potentially fniitless process of uniquely identifiing single particles as to chernical composition, surface features, fuel derivation or geognphical source.

In sumrnary, using Plate 1 1 to illustrate the "forensic approach" described in Part

IV of the Results (above), five categories of "groups" and 'kubgroups" of particles were establislied on the basis of combustion features and particle characteristics. En Plate 1 1,

Figures 1 to 5, the first of the categories is the subgroup "lacy comples opaque spheroidal particles". The sirnilarity of the particles is related to tlieir carbonaceous composition and fossil fuel origin as fuel droplets or particles (Plate 2 and 3). In the second subgroup of

"esternally cornplex opaque spheroidal particles" (Plate 1 1, Figures 6 to IO), the particles corne frorn a variety of fuel types, including waste buming (Plate 4), which may also contain biomass (Plate 1), fossil fuel-derived products and other materials that give rise to particulates. These particles are related by morphology pnmarily. In the third category, 114 the group of "simple opaque spheroidal particles" (Plate 1 1. Figures 1 1 to 15), the

particles are from environmental samples and coal fly ash (see Plate 3), but were also

observed in oil fly ash (Plate 2): including diesel fuel combustion in stationary facilities

(Plate 5, Figures 16 and 17) and vehicles (Plate 6, Figures 3 and 4). In the fourth category

a subgroup (Plate 1 1 Figures 16 to 2 L ) of compiex non-opaque spheroidal particles, the

particles are from coal fly ash from different coal burning power generating facilities

burning the same coal. and from environmental sarnples in the Belcher Islands. These

particle types are apparent in coal fly ash (Plate 2, Figures 2 and 7), as well as incinerator

fly ash (Plate 4, Figure 12). In the case of the fourth category, the parallels between the power plant particles and the environmental particles from the Belcher Islands are very stronç. Although the effects of taphonamy are beyond the purview of this thesis, it is very tempting to attribute the differences within this group of particles to taphonorny.

The fifih category is a subgroup of the comples non-opaque spheroidal particle group, illustrated for purposes of this discussion by Plate 1 1 (Figures 22 to 25). These particles are from combustion-related ireference particles, in this case catalyst particles, and from environmental sarnples from the Belcher Islands wliich share n~orphological features in shape, serni-transparency and surface characteristics. In the case of Plate 1 1,

Figures 22, 24 and 25 also share the distinctive straw yellow colour.

3.12. Conclusions

Recognizing that different fuel types generally respond in similar ways to combustion processes, but that heterogeneity in the fuel will result in heterogeneous 115 mises of combustion products as well as heterogeneous particles, and that the combustion process itself can serve to modulate the products generated, means that classification of combustion products must necessarily address ambiguity as well as distinctiveness.

To this end, a functional, artificial classification is proposed, based on studies reported in the literature, and on my efforts to document combustion particles in the arctic environment. This classification consists of a diagnostic key to aid in identification, and a synoptic key to report the classification developed for interpretation of paleoecological records from sediments. It should be noted that this approach to classification was developrd for specific purposes ofpaleoecological combustion inventories in the Arctic, a remote area where low levels of regional ernissions are expected. Consequently, it may or may not be appropriate for use in other more heavily industrialized areas; but such considerations are beyond the scope of the present work.

I do not mean to suggest that tliis classification is intended to be definitive or absolute: it is really a beginning. The process of the development of this purpose-oriented classification is iterative and open-ended. lmprovements will continue to be made as this work continues with the documentation of additional particles from additional sites, environmental niedia (such as snow and glacier ice) and sources.

In subsequent chapters, this approach to classification is applied to the problem of spatial and temporal distribution of combustion products in the arctic environment. CHAPTER 4

COMBUSTION PARTICLE OCCURRENCE IN SEDIMENT CORES AT

ALERT, ELLESMERE ISLAND, NUNAVUT

4.1. Introduction

Tne question of the feasibility of using combustion particle occurrence in Lake and

pond sediment cores from the Eastern Arctic to investigate environrnental change in

relation to anthropogenic activity was one of the original starting points of this research.

My interest in this paleolimnological study originated with my perception of the

ecological importance of contarninants in general, coupled with the recognition that

paleoecological approaches, particularly those rooted in paleolimnoIogical research, have

demonstrated vaIue in assessing environmental change through time (Charles et al., 1994;

Smol. 1995). In addition, my previous experience in reconstmcting fire history at a

regionaf scale served as an analog for the extension of paleolimnological investigation of

combustion particle occurrence to the probiem of arctic contarninants (Terasmae &

Weeks (Doubleday), 1979). In that case, fire represented a proxy for long-term

environrnental change in relation to clirnate and vegetation.

At an earlier stage of the present work, we observed that at Lower Dumbell Lake,

Alert, Ellesmere Island, the sediment record of occurrence of one type of combustion

particle does fdlow a general pattern (Doubleday et. al., 1995). This pattern can be

described as follows: at some depth in the core, representing an earlier depositional stage, a threshold is observed at which spheroidal black particles identified with combustion appear. These combustion particles and, consequently, the carbon that they contain, 117 become more abundant in more recent sediments. This pattern is most comrnonly expressed as a profile of occurrence with depth, with the top of the diagram representing the sediment surface or top of the core. This pattern is found in environmental studies of sediments from a variety of disciplines, but paleoecological, sedimentological and geochernical studies have contributed most significantly.

As has been demonstrated for highly industrialized regions, there is a relatively low rate of increase of particles initially, which rises much more sharply with increased

Utilization of fossil fuels (Griffin & Goldberg, 1979, 198 1; Goldberg, 1985). These earlier works noted the transition from the dominance of wood charcoal in sediments to coal combustion soot, and then to petroleum combustion products, as the sediment core surface is approached and the sediments investigated become more recent. This increase in abundance of combustion-derived carbon, including spheroidal carbonaceous particles

(SCP), then achieves a maximum, frequently dated in European studies to approsimately

1970 (Wik, 1993; Rose, 199 1). Following this maximum, levels of SCP then generally appear to decline somewhat, not necessarily in a uniform manner, to a reduced level at the sediment surface, corresponding to the most recent period of deposition.

It is interesting to note the striking resemblance between the pattern of SCP occurrence in sediments observed in industrialized regions and that of profiles of various pollutants in sediments (Charles & Hites, 1987). The existence of this well-documented pattern of SCP occurrence in industrialized regions has a number of possible applications, notably the potential for use of SCP profiles as a proxy for other forms of dating on a regional scale (Renberg & Wik, 1985): as a marker for sedimentation patterns (Wik & Renberg, 199 l), and as a correlate for other forms of pollutants associated with

combustion, such as sulphur deposition (Rose & Juggins, 1994).

Alderton (1 985) discusses sediment profiles of a variety of environmental

pollutants including mercury, lead and zinc. Work by Barnes & Schell(1973) and Kemp

et al. (1976), as reported by AIderton (1985), and results obtained by Gschwend & Hites

(1 98 1)- for example, show lower contaminant levels at increasing depth in the sediment,

corresponding to earlier penods of tirne. While issues of mobility of metals and organic

compounds in sediments have not been wholIy resolved, the increase in contaminant

levels in recent times has been generally accepted as a reasonable reflection of increasing

ernissions to the environment. Contributions by researchers with an interest in sediment

geochemistry as well as ecological effects in the Arctic have presented evidence of

distributions of metals and organic contarninants in arctic sediments that resemble those

of temperate industrial regions in profile (Lockhart et al., 1993; Muir et al., 1995;

Lockhart, 1995).

The above pattern suggests that evaluation of the SCP content of sediments might

possibly serve as a surrogate for other forms of sediment analysis for contarninants, at

least in the first instance. in assessing the likelihood of anthropogenic impact at a

particular site. It also simulated my interest in the possible application of studies of SCP

in sediment cores as a means of acquiring additional information about spatial and

temporal distributions that might be associated with specific contaminant impacts, and more generally with the effect of global anthropogenic activity on the arctic environment.

The work of Barrie (1986), Bame & Hoff (1 985), Barrie et al. (1 W?), Hopper et al. (199 1) and Patton at al. (199 l), using data from Alert and elsewhere, have demonstrated the occurrence of atmospheric long-range ininsport of various contarninants, many of which are associated directly with combustion in one form or another, into the Canadian Arctic from Eurasian sources, providing another rationale for a survey of combustion particulates in the Arctic.

There are strong incentives for identification of indicators and methods of assessment of contaminant occurrence, flowing from increasing public awareness of the relationship between human and ecosystem health. In addition, legal and policy issues related to the international law of transboundary pollutants and their impacts provide an impetus for regulation. Ln the case of the Arctic, many issues arise from increasing concern about contamination, both at an ecosystem scale (Wong, 1985; Greenaway et al.,

199 1; Sturges, 199 l), and in specific locations (Bright et al., 1995a, 1995b). These issues relate to the long-term health and viability of arctic ecosystems, terrestrial, freshwater and marine, as wel! as to the safety of traditional foods of Inuit and First Nations residents who are heavily dependent on wildlife (Wong, 1985; Condon et al., 1995). In addition, the identification of sources, pathways and ultirnate sinks for V~~OUSpollutants is vital to international efforts to control contarninants, and to understanding and mitigating ecological effects. For further discussion of these points, see Doubleday (1 997).

The evidence of coherent temporal patterns of contaminants in sediments from arctic lakes, coupled with the documentation of spatial and temporal distributions of combustion products, and the research that has begun to draw associations between the two, leads to the question that is the focus of this chapter: 1s it possible to detect temporal 120 patterns in the distribution of combustion particles in sediments from the High Arctic in Canada, specifically from the AIert area? If so, the next question which must be addressed is the extent to which patterns of occurrence of combustion particles in sediments in the Arctic resemble those found ekewhere.

As a first step in the investigation of these questions, 1 present the results of a reconnaissance level case study of combustion particle occurrence at two sites, Self Pond and Kirk Lake. near Aiert, Ellesmere Island, Nunavut. Reference is aiso made to previously reported work done at a third Alert site, Lower DumbelI Lake (DoubIeday et al., 1995). These sites constitute the most northerly points of a broad transect extending to the Belcher Islands, which is reported in Chapters 5, 6 and 7.

1.2. Study sites

1.2.1. Fcatures of the area of Alert

Alert is a High Arctic Weather Station and rnilitary base located at the north end of Ellesmere Island (see Figure 4.1 .), the most northerIy island of the Queen Elizabeth

Islands, at 82O30'N and 63O26'W. It is 832 km from the North Pole (Reimer, 1985). It was chosen for this study as one of the most northerly. accessible points near the Arctic

Ocean that lies on one of the atmospheric trajectories postulated for transpolar transport.

Also, the Atmosphenc Environment Service (AES) has conducted extensive research at this site (Gray, 1997) and operates a year-round atmospheric research facility. Coupled with these factors, the benefit of logisticd support of the Department of National Defence

(DND), which provided access to CFB Alert as a base camp, made Alert a viable choice. 121 Johnson (1990) has described the entire area from Alert to the tvest side of

Upper Dumbell Lake as having low relief. The terrain is an unsorted rnix of heavy clay

and till, part of the glaciomarine sediment deposits described by Retelle (1986). Reimer

(1985), citing Chong & Mattes (1 979), describes the surficial geoIogy of the area

imrnediately surrounding Alert as follows: "(t)he surface soi1 consists of shale intermixed

with silt and clay. Outcropping shale beds frequent the area, and these decompose readily

~6thweathering and traffic to a grey powder; grzyhrown thereby characterizes the

landscape (coIour)".

Ellesmere Island is in the zone of continuous permafrost, with an active layer in

the Alert area that is Iess than 0.8 m deep (Taylor et al., 1982). Surface aspect has little

effect on permafrost occurrence (Taylor et al.. 1982). Vegetation is patchy and sparse

(personal observation).

4.2.2. Study site descriptions

The Self Pond and Kirk Lake sites were chosen for a number of reasons reIated to

intrinsic characteristics and geographical factors. Figure 4.1. shows the locations of these

sites. Both are larger and deeper that most of the small ponds present, yet not as large as

the Dumbell Lakes, which are the largest lakes in the vicinity. In addition, these sites

were the most distant from the military base, CFB Alert, to which we had access, and

were expected to be less influenced by activities at the base, than sites nearer the

facilities. As Self Pond and Kirk Lake occupy different quadrants in relation to the

location of the base, these sites are expected to experience different degrees of exposure to local influences depending on the effects of prevailing winds. Therefore this choice FIGURE 4.1. Map of study sites at Alert, Ellesmere Island, Nunavut. Adapted from a base map by C. Earl, pubIished in Johnson, 1990. Mushroom Point

Ellesmere Island 123 of sites should emphasize the between-site differences, allowing detection to sorne extent of the influence of local activity. The sarnpling process is described below, and further detaiIs of the field work are provided in Appendix 4.1.

4.2.2. (a) Self Pond

Self Pond is located at 82O26' 19 N, 62"02'25W, approximately 9 km SSE of CFB

AIert. Self Pond is approximately 37 ha in area. It lies north of the Sheridan River, on a relatively unvegetated clay plain between the heights of land to the south known as

Mount PuIIen (elevation approxirnately 414 m a.s.l.), Dean Hill (elevation 394 m a.s.l.), and a small hiII to the north (approsimately 154 m a.s.1.). It drains into an unnamed tributary of Ravine Creek, which lies to the north. Self Pond is situated between the contour lines indicating 120 and 180 m above rnean sea level, to the north of the Sheridan

River sheet (Map Sheet 120 E/5, Energy, Mines & Resources, Canada). The land surface shows relatively Iittle dramatic relief in the immediate vicinity of Self Pond, but is gently undulating. Farther to the south-west, Mount Pullen and Dean Hill are part of a ndge delimiting the watershed. According IO mapping by Taylor et al. (1982), Self Pond lies within the maximum marine limit and above the shoreline position that existed approximately 8000 yrs BP. Tucker & Judge (1991) cite England (1976) in placing emergence in this area since then, at approximately 60 m. The pond itself is steep sided, escept for an area on the southwest shore, where surface runoffhas eroded and redeposited material creating a more gradua1 slope, both on shore and offshore.

During the initial site visit extensive, turbid runoff was observed flowing over this slope. In Self Pond, below the surface of the water, the bottom gradually slopes from the 134 southwest shore toward the centre. This slope provided easy access to the pond for

hand push coring. Given the potential for, and evidence of, an increased flow of eroded

material into Self Pond at this point, it was not an ideal site, but at least sarnples could be

taken.

4.2.2. (b) Kirk Lake

Kirk Lake is located at 82O27'N, 63"49'W, approximately 11 km WSW of CFB

Alert. Kirk Lake is approximately 100 ha in area, and on the topographie map sheet (Map

Sheet 120 E/5, Energy, Mines & Resources, Canada) appears belotv the 60 m contour line. In terms of emergence due to isostatic rebound, Kirk Lake would seem to be more recently esposed than Self Pond. To the south, a ridge comprises the top of the slope adjacent to the lake, and continues to rise to an unnamed height of land with an elevation of approximately 360 m. some 4 km further south. As in the case of Self Pond, active transport over the surface of the surrounding slope can be espected during the period when the combination of isolation-induced heating and ambient daily temperature is high enough to cause melting, or on the reIatively rare occasions when precipitation in the form of heavy min occurs (Hardy, 1996).

Kirk Lake drains into Colan Bay, an arrn of the Lincoln Sea, and is within a few kilometres of the sea, whereas Self Pond is approximately 8 km from the Coast.

Presumably these two sites will have experienced somewhat different post-glacial histories as a result of different dates of emergence (Retelle, f 986).

4.2.2. (c) Lower Dumbell Lake

Lower Dumbell Lake (82'29' 40" N, 62'35' 65" W) is a large lake situated 125 approsimately 4 km West of Alert, with an area of approximately 180 ha. There are a number of unsurfaced graded roads and tracks for vehicles and for utility maintenance in the vicinity. This site was chosen for the preliminary trial of paleoecological techniques and approaches to the assessrnent of tlie record of black carbonaceous particles in the

Alert area.

4.2.3. History of hurnan activity near the sites

In the High Arctic, human activity cm generally be separated into two basic time periods: the pre-European contact Paleoeskimo penod extending back several thousand years, at wliich time Independence 1and II peoples were thought to have travelled the shore of Lake Hazen; and the post- European contact period which, if one includes Norse esploration and settlement of Greenland, can be dated as early as 1000 years ago (pers. cornm. Dr. R. McGhee). The period of post-contact human activity in northern Ellesmere can be fiirther divided into two major stages, one linlced to early exploration, exploitation of marine resources and discovery; and the second. related to tlie threats associated with

çeopolitical forces in the modern world, particdarly World War II and the ensuing Cold

War (pers. comm. K. Greenaway, Gray, 1997). There is Iittle evidence of human activity stemming fiom the early phase of polar exploration in the immediate vicinity of these two sites, although on the Coast to the east, historical sites, such as Fort Conger, have been designated. The impacts of the second stage of post-contact activity are, however, more visible in relation to the sites under investigation.

During World War II, the Allied rnilitary establishment gained an appreciation of the strategic advantages offered by great circle routes. northern landing strips, and 126 advance notice ofweather conditions in the North Atlantic. When the U-S- S. R-

becarne a major world power, an appreciation of the role of the Arctic in strategic terms

dawned. An authoritative account of the founding of Alert, as the fi& of the Joint Arctic

Weather Stations established in the Queen Elizabeth Islands by the United States and

Canada, has been given by Johnson (1990). A wide-ranging and Iess formal account of

the history of CFB AIert has been written by Gray (1997).

SeIf Pond appears relatively undisturbed by human activity in the immediate area.

It is near a travelled route to Mount Pullen, a popular excursion destination for off-duty personnel from the base, but does not show indications of human use.

In comparison with Self Pond, Kirk Lake is much more regularly used by staff from the base. There is a small recreational cabin for use for local leave, and the usual outdoor recreational activities associated with such a facility are to be espected.

Lower Dumbell Lake is adjacent to a frequently used, unsurfaced track and is west of Upper Dumbeil Lake. Lower Dumbell is not as lieavily used as Upper Dumbell Lake, which is the water supply for the base and has undergone a number of related modifications. In 1979, a clean up team removed debris from Upper Dumbell including

75 barrels, bedsprings, wire and other materials, but there is no mention of a similar clean up at Lower Dumbell (Gray, 1997).

A study by Reirner & Wolfe (1985) investigated the water quality of the adjacent

Upper Durnbell Lake, which is the source of water for the military base, and found no

'linusual" levels of metaIs, with the exception of some possible seepage containing iron and cadmium at levels somewhat higher than in neighbouring samples. This was not seen as a 137 significant concem and was noted for future study in relation to an abandoned

transmitter site up dope. Analysis of metals in soils fiom Alert, reported in the same study,

found no results inconsistent ~4ththe site history of local activities, such as sewage outfalls

at Parr Inlet (now Alert Bay). In terms of anthropogenic impacts on individual Iakes, Upper

Dumbell Lake has been the object of direct human intervention, such as construction of a

quay to house the pumphouse and its generator (Reimer & Wolfe, 1985). There is no

evidence of direct antlzropogenic impacts at Lower Dumbell Lake, Kirk Lake or Self Pond,

but indirect influences are Iikely, given the current use of the area.

4.3. Matcrials and Methods

This section treats in detail the previoudy unpublished work with regard to Self

Pond and Kirk Lake. In the results section below, data obtained in an earlier published

study of samples from Lower Dumbell Lake (Doubleday et al., 1995) are included in the

discussion witli results from Self Pond and Kirk Lake. The Lower Dumbell Lake work

reflects a very early stage of development of tlie present approacli, using different

Iaboratory and microscopical techniques. The results of tlie Lower Dumbell analysis have

been converted to relative abundance of combustion particle types as a percentage of total

particles counted. However, as a note of caution, the differences in sample processing and

enumeration must be borne in mind. A description of the methods used in handling of previously published data for the Lower Durnbell Lake samples is given in Doubleday et al. (1 995).

4.3.1. Sampling

The Self Pond site was accessed by helicopter as result of a spontaneous 128 offer of transport assistance from a forensic investigation team active at Alert at the

time. There was Iittle time or capacity for arranging for bulky equipment or sophisticated

procedures, but in order to make the most of the opportunity, I took a minimal kit needed

to obtain "push cores". A military staff member was assiçned for safety reasons, and we

were given a 1.5 hour window of opportunity between drop off and pick up. In a

subsequent trip to the site, additional military personnel were assigned due to difficulties

expenenced in the first attempt. Between these bnef trips, a number of surface samples

and push cores were taken. Surface samples were "grabbed" manually using plastic bags.

Pus1-i cores were taken using Lucite tubing with a diarneter of 5 cm, which were forced into the Lake bottom with body weight. The tubes were then rnanually extracted, sealed witli rubber stoppers, as soon as the bottom of the tube cIeared the watedsediment interface. and brouçht ashore for labelling. As there was not enough time to subsample on site. the first core taken was transported in the coring tube supported in an upright position to CFB Alert. SubsampIing of this core was done Iater in a garage at the base.

Siibsequent cores were subsampled in the field, as time was less of a constraint. Sediment cores and grab samples consisted of extremely thick clayey material, dark gray in colour and without readily visible structure or other notable features. Subsectioning of the push core was done at 0.5 cm intervals, using an interval sectioning device (Glew, 1988). Al1 sarnples were double bagged in WhirlpakTMbags, labelled and stored.

Access to Kirk Lake was provided by a tracked all-terrain vehicle, thanks to the

Commander and personnel of CFB Alert. A moat had begun to open near the grave1 beach, and we used a small zodiac as a platform. Further down the shore away fiom the 129 beach, the remaining land-fast ice served as a bridge. The sedirnent sampling was done through the ice, and from the side of the zodiac, using a Glew mini-gravity corer

(Glew, 199 1)- The water was 1.8 to 2 m deep at points were cores were taken. The bottom displayed some variation. Sediments ranged from stiff grey-black, clay-like material to quite coarse, granular black material. The cores were subsectioned in the field at 0.5 cm intervals. using a field interval sectioner (Glew, 1988). Samples were double bagged in

WhirlpakTMbags, labelled and stored. The core used for this study (Core 5, JPS-92-Kirk-

5) was just over 7.5 cm long. The sediments in other Kirk Lake cores were fine-grained and dark grey to black' but in Core 5 the sediments were noticeably different, with very coarse granular material. This material appeared in the top 4 cm of Core 6 as well, with the lower 3 cm of Core 6 resembling the dark grey to black sediment of Cores 1 to 4.

Core 5 \vas taken from the ice edge tlirough the moat in 2 m of water, directly opposite the recreational hut.

Menwe took cores from Lower DumbeII Lake on July 17,1992, the lake was stitl largely ice covered. A moat appro~imately10 m wide was present, but it was possible to walk to the ice in some places. The bottom \vas very rocky. Cores were recovered through holes drilled through the ice using a manual ice auger at Hole 1, and taking advantage of sinkholes caused by meltwater drainage for Holes 2 and 3. The first core fiom Lower

Durnbell (JPS-92-LDL-HIC 1), at 82O29' 15.Y7N, 62" 35'58.4" W, was taken through a blanket of ice and snow exactly 2 m thick, at a depth of 30 m. This core was just over 6.0 cm in length. The Lower Durnbell core for which data are presented in this study was Core

2 taken at Hole 3 (JPS-92-LDL-H3C2), in approximately 20 m of water, using a Glew mini- 130 graviv corer (Glew, 199 1). Hole 3 \vas located at approsirnately 1 m from Hole 2

(82O29' 19.6"N7 62°35738.57'W).Core 2 was slightly longer than 10 cm, grey in colour and of clayey consistency.

4.3.2. Laboratory methods

The sediments frorn cores from Self Pond (Core 3 JPS-92-Self Pond-;) and Kirk

Lake (Core 5 JPS-92-Kirk Lake-5) urere subsampled. taking care to minimize exposure to ambient air, by working in a Class 100 clean air cabinet. These subsarnples were then placed in stenle glass or plastic vials. and covered and freeze dried at facilities of the

Geoloçical Survey of Canada and the Canadian Museum of Nature. After freeze-drying, subsamples were again removed. weighed and transferred to centrifuge tubes for processing. Unfortunately it was not possible to position an analytical balance in the cIean cabinet in order to complete the weighing because of the vibration of the unit. The method adopted was to make trials of volumes of freeze dried material, then weigh them on an analytical balance to acquire a sense of the volume of freeze dried sedirnent needed to make up a subsample approaching the desired mass (0.1 g). Sirnilar volumes were then taken from the freeze dried samples, and transferred to clean centrifuge tubes that Iiad previously been weighed with their tops. The centrifuge tubes containing the samples were sealed in the clean cabinet and taken to the balance to be weighed. The weight of the sealed centrifuge tube plus sample was recorded, and the weight of the corresponding centrifuge tube and top alone was deducted to yield a net sarnple mass.

The freeze dried samples were processed using a chernical digestion process developed by Rose (1990), revised (Rose, 1994), and subsequently modified by me 131 through omission of the Iiydrofluo~cacid step. Sediments were digested with hot nitric and Izydrochloric acid, to remove minerais. organic matter and carbonates. Afier completion of the digestion process, a suspension of the residue was prepared by diIution to a knotvn volume. Aliquots (200 pm) of this suspension were then transferred to clean glass coverslips (22x22 mm) with an en en dot-f" pipetter, with disposable tips. A new clean tip was used for each sampie to avoid cross-contamination. Four replicates were made of each sample. The coverslips and sarnpIes were Sien dried in a slide warrner, covered and mounted inside a clean cabinet acid fumehood for at Ieast 12 hours. When dry. the coverslips were mounted on clean glass slides with FIyra~"or ~a~hrax@ niounting media and labelled immediately.

3.3.2. (a) Lower Dumbell Lake Samples

The Lower Dumbell core (JPS-92-LDL-H3C2) \vas processed as described in

Doubleday et al. (1995) using the method of Odgaard (1993). The marker grain method for determining pollen concentration was adapted for combustion particles as described by Stockmarr (1971) and de Vernal et al. (1987). Original counts were transformed to percentage relative abundances for present use (Appendix 4.5).

4.3.2. (b) Microscopical rncthods

The slides were analysed with a Reichert Research Microscope, fitted with a tungsten filament light source, transformer and polarizing filters. Nikon and Minolta cameras were mounted on the carnera port. The carnera was fitted with a cable release.

Observations were made primarily with transmitted light. In addition to polarizing filters, the microscope was equipped with neutraI gray, blue, and green filters. The 132 polarizing, blue and green filters were the most frequently used. Indirect top Iighting

was also used.

Categories of particles to be enumerated were established, as previously discussed

(see Chapter 3,and count sheets were prepared. Counts were of the complete area of the

coverslip, usually at a magnification of 4OOX, with the use of a high dry objective for

study of individual particles at higher magnification.

4.3.2. (c) A note concerning Lower DumbelI Lake analyses

The Lower Dumbell Lake results were obtained in an early stage of the present

work. These data have been converted to percentage relative abundance, based on the

total number of combustion partides observed. However, I view the results of the Lower

Dumbell Lake study as being of interest, but not directly comparable to the results from

Self Pond and Kirk Lake, due to differences in laboratory and microscopical methods,

(and in investigator esperience) as reflected in Chapter 3.

4.4. AnalyticaI and statistical mcthods

The particles observed were first classified as to type. as discussed in Chapters 2 and 3, then counted in the appropriate category of the count sheet. At the end of the

counting process, the results obtained were recorded in a database organized by particle category and sample identification label.

In the section on Iaboratory methods above, I discussed the difficulties associated with preparing the samples to avoid contamination during weighing. My decision to emphasize preparation quality resulted in the requirement to adjust the raw counts to a base or "standard" sample mass in order to compare them. Following completion of the 133 counts, and entry into the database, ratios were taken to adjust the raw counts to a

standard sarnple mass, in this case 0.10 g of sediment (dry weight). These adjusted

sarnple count values were then summed across al1 types and al1 samples to yield a grand

total that could be used to calculate the relative abundance of any of the types present in

the form of a percentage of this total. These values were rounded, usually to the closest

integer, but in some cases, up to two decimal points were retained. As a result, a small

source of potential error due to rounding is introduced, but in no case does this exceed

1% of the total relative abundance. Data for raw counts and for adjusted values for Self

Pond, Kirk Lake and Lower Dumbell Lake are included in Appendices 4.3,4.4, and 4.5,

respectively.

Histograrns representing the distribution of combustion particle occurrence at each

site with depth were then constructed to show relative abundances of combustion

particles by type. for al1 combustion particles enumerated. For purposes of clarity and

emphasis in some instances' the values for the relative abundance of selected particle

types or groups of types were extracted from the distribution of the total particle

inventory for the site and presented separately as a chart of the contribution of that

particle type to the total relative abundance of combustion particles of al1 types, usually

with sediment depth.

The classical histogram, reflecting the particle distribution in the entire sarnple suite for each core, was the preferred mode of representation of the results of this

inventory. The geographical distribution of combustion particles observed from the transect from Alert to the Belcher Islands, of which this Chapter reports only a portion, is discussed in the concluding chapter.

4.5. Results

4.5.1. Descriptions of combustion particles €rom the Self Pond site

The following classes of particle types were documented in the Self Pond

sarnples:

1. spheroidal carbonaceous particles

2. non-black spheroidal particles

3. pleurospheres

4. cl~arcoalparticles

5. amorphous opaque combustion particles

6. amorphoiis opaque-non-opaque

7. coal-type particles

8. glassy rods

9. aciculate spheroids

10. aciculate masses

As discussed in Chapters 2 and 3, CIasses 1 to 6 are clearly associated with combustion,

but classes 7 to 10 are excluded frorn combustion totals, as their provenance cannot be

proven unequivocally at this time (see Chapter 3 for a discussion of these types). In the

classification system described in Chapter 3, the standardized terrns for classes 5 and 6, are '%ombustion amorphous opaque" (abbreviated as "cmarnop"), and "combustion amorphous opaque-non-opaque" (abbreviated as "cmmix"), respectively. 135 The counts made in the combustion categories were tabulated as described

under materials and methods, and the histograms were prepared, based on the adjusted

values. 4.2. (a) displays the relative abundance of the combustion particle types as a

percentage of al1 of the combustion particles enumerated in the Self Pond samples. The

particle type distribution is dominated by spheroidal carbonaceous black particles (58%), followed by non-black spheroidal particles (24%), combustion mixed opaque non-opaque

(1 0%). Of the other types present, the class 'kombustion amorphous opaque", labelled

--cmamop". represents approsimateIy 5% of the total. The remaining classes are present at even Iower levels: charcoal (1-2%), pleurospheres (CI%), and combustion angular opaque (CI %).

The distribiition of al1 combustion particle types found in the Self Pond samples with depth is given as a histogram in Figure 4.2.(b). Between the core sediment surface and 5 cm in depth, values are presented for each subsarnple slice at 0.5 cm intexvals. The values given for depth correspond to the endpoint of the subsampling interval. An additional sarnple, representing the bottorn of the core at 9.5 cm, is included for comparison with the surface sarnple. The profile of total combustion particle distribution with depth for the samples analysed indicates a maximum at a depth of 2.0-2-5 cm. This

Iayer accounts for slightly more than 25% of the total combustion particles observed in the samples from this core. The upper half of this profile, including the 2.0 - 2.5 cm sarnple, contains approximately 71 % of this total combustion partide distribution. In comparison, the contribution of the bcttom sample (9.5 - 10.0 cm) is approximately 3% of the total. This is similar to the Ievel found at 4.0 - 4.5 cm, and is less than that of any of FIGURE 4.2. Self Pond, Alert, Ellesmere Island, Nunavut. (a) The relative abundance of the combustion particle types is displayed as a percentage of al1 of the combustion particles enumerated in the Self Pond samples. (b) The distribution of ail combustion particle types found in the Self Pond samples with depth (cm) is given as a histogram. Cornbustion particle type

KEY SPCBK - spheroidai, carbonaceous, black type cmamnop - combustion, morphous. non- SPNBK - spheroidal, non-black type OPaque Q"pe Psph - plcurosphere type crnanop - combustion angular opaque type chtot - total charcoal of a11 types cmnii~- combustion mised opaque-nonopaque cmamop - combustion, amorphous opaque type type

O 5 10 15 20 25 30 Relative abundance (~'uJ 137 the other subsamples. Figure 4.3. (a) shows the distribution of the Self Pond charcoal fraction of the histograrn for total particles with depth, in an exaggerated fashion. Levels are very low in relation to those of other combustion particle classes. It is interesting to note, however, that the distribution is disjunct, with charcoal detected in only 3 of 10 sarnples, none of which were adjacent.

Figure 4.3.(b) presents the distribution of the spheroidal carbonaceous black particles with depth, as a percentage of the total combustion particle distribution for Self

Pond. It sliouId be noted that the scale on the x-axis has been changed by a factor of two, in order to emphasize the shape of the profile for this class of particles in the core.

4.5.2. Descriptions of combustion particles from the Kirk Lake site

At Kirk Lake, the classes of particle types recorded were:

1. spheroidal carbonaceous particles

2. non-black spheroidal particles

4. cliarcoal particles

5. arnorphous opaque combustion particles (including "diesel particles")

The counts made in the combustion categories for Kirk Lake were tabulated as descnbed under materials and methods, and adjusted to a standard sample mass of 0.1 g dry weight of sediment, for comparability. Histograms were prepared, based on adjusted values. Figure 4.4. (a) displays the relative abundance of the combustion particle types as a percentage of al1 of the combustion particles enumerated in the Kirk Lake core. This histogram highlights the contributions from the spheroidal carbonaceous black (62%) and charcoal (30%) particle types. The remaining 8% of the total combustion particle load FIGURE 4.3. Self Pond, Alert, Ellesmere Island, Nunavut.(a) The distribution of the charcoal fraction of the histogram for total particles in the Self Pond core with depth (cm), show in an exaggerated fashion. (b) The distribution of the spheroidal carbonaceous black particles (SPCBK) with depth, as a percentage of the totaI combustion particle distribution for Self Pond. It should be noted that the scale on the x- ais has been changed by a factor oftwo, in order to emphasize the shape of the profle for this class of particles in the core. Lnot analyseci

O 2 4 6 8 10 12 14 16

Relative abundance (O!

shaded axis denotes O value + + 1 0.2 0.3 Relative abundance (%) FIGURE 4.4. Kirk Lake, Alert, Ellesmere Islandt Nunavut. (a) The relative abundance of the combustion particle types displayed as a percentage of al1 of the combustion particles enumerated in the Kirk Lake core. This histogram highlights the contributions from the spheroidal carbonaceous black (62%) and charcoal (30%) particle types. The remaining 8% of the total combustion particle load is composed of non-black spheroidal type particles and diesel-type particles which are classified as "combustion, arnorphous, opaque" (crnarnop), (b) Histogram showing the relative abundance of totaI combustion particle occurrence with depth (cm) in the Kirk Lake core. The core was sectioned continuously at 0.5 cm intervals between the top of the core and the bottom. The values on the y-asis correspond to the endpoint of each sampling interval, one subsampre being analysed at each interval. SPCBK SPNBK Diesel-type chtot Combustion particle types

KEY SPCBK - spheroidal, carbonaceous, black type SPNBK - spheroidal, non-black type diesel-type (cmgen) - combustion generic type (black) type chtot - total charcoal of al1 types

0.5 1 1I 1 1.5 i 1 2.5 1 h .. - 1 5 3.5 1 Y 5e 4.5 1 8 l 5.5

6.5 shaded axis dcnotes O value

7.5 1 O 5 10 15 20 25 Relative abundance (%) 140 is composed of non-black spheroidal type particles and diesel-type particles which

are classified as "combustion, amorphous, opaque" (cmarnop).

Figure 4.4. (b) presents a histogram of total combustion particle occurrence with

depth in the Kirk Lake core. The core was sectioned continuously at 0.5 cm intervals

between the top of the core and the bottom. The values on the y-asis correspond to the

endpoint of each sampling interval, one subsample being analysed at each interval. The

interval at 1.5 - 2.0 cm represents the Iargest single contribution to the total combustion

particle load, accounting for approximate 31%. The section of the core from this layer to samples analysed, is presented in Figure 4.5. (a). Note that the scale used for the s-ais lias been enlarged by slightly more than a factor of two in order to highlight the profile of the distribution. Given that this particle type contributes almost two-thirds of the combustion particles which occur. it is not surprising that the distribution of spheroidal carbonaceous black type particles Iooks very sin~iIarto that of total combustion particles in Figure 4.4. (b). SPCBK type particles were not observed behveen 5.0 and 7.5 cm. The charcoal particle distribution for Kirk Lake is shown in Figure 4.5. (b). It should be noted that the scale of the x-ais is magnified by about 30% in relation to the s-axis of 4.5. (a), for emphasis. The profile of charcoa! particle occurrence, espressed as a percentage relative to the total con~bustionparticle census, shows a maximum just below the top of the core, at the 0.5 - 1.O cm level, where approximately 8% of the charcoal particles occur. The lowest levels of charcoal occur down core, at 4.0 - 4.5 and 4.5 - 5.0 cm, where it represents about 1% of the totaI combustion load in the samples analysed. Charcoal was absent between 3.0 and 4.0 cm, and behveen 5.0 and 7.5 cm. 141 45.3. Descriptions of combustion particles from the Lower Durnbell Lake site

As was indicated previously, the sarnples from this site were treated and analyzed at an earlier stage of this research, prior to final decisions about methods of processing, mounting and counting. Values that were originally expressed as concentrations of opaque spherical type particles terrned "soot" or "spherical carbonaceous particles?', at this early stage, have been converted to percentage relative abundance (see Appendix 4.5): so that the combustion particle record in Lower Dumbell

Lake is espressed in similar terrns. A histogram, sirnilar to those discussed for the Self

Pond and Kirk Lake sites, has been prepared for the Lower Dumbell core. Diatom analyses were made by M. S. V. Douglas for the Lower Dumbell core (JPS-92-LDL-

H3C2) which indicated no diatom occurrence below 1.5 cm (Doubleday et al., 1995). In

Lower Dumbell Lake the depth of the core in which the diatom record occurs corresponds approsimately to that of combustion particle deposition. A recent, general warming trend is inferred from diatom records at Cape Herschel, Ellesmere Island (Douglas, Ph.D.

Thesis, 1993) and a similar situation may have esisted in northern EIlesmere Island.

4.5.3. (a) Combustion particlé types

Two categories were used to describe and group combustion particles in the earlier study of Lower Dumbell Lake sediment core JPS-92-LDL-H3C2, prior to the classification work reported in Chapter 3: soot, meaning spheroidal black particles; and charcoal, meaning combustion particles with biomass features. At an early stage of the investigation, prior to the development of the classification and the refmement of procedures. the pnrnaiy concern was whether or not combustion particles could be studied in this environment. The recognition of the potential for application of additional types of particles came later.

1-53.(b) Distributions obsenredfrorn Lower Dumbell Lake

The results obtained for combustion particle types in samples from Lower

Durnbell Lake core JPS-92-LDL-H3C2 were converted to percentage relative abundance based on the total combustion particles observed. The percentage relative abundance of soot type and charcoal particles with depth in Lower Dumbell Lake is given in Figure 4.6,

The distribution of combustion particles with deptli follows a similar profile to that observed in Self Pond and Kirk Lake, with a ma.ximum within 1 cm of the sediment surface, and a rapid decrease in relative abundance of particles with depth, to none observed beyond 2.0 - 2.5 cm deptli. The value reported at 2.0 - 2.5 is only 0.3%: and cl%. appears as 0% due to rounding.

Without "O Pb dating and reliable sedimentation rates, and lacking stratigraphic controls, it is problematic to attempt to relate differences among these sites to one anotlier. However, it should be noted that core JPS-92-LDL-H3 C2 was taken in approsimately 20 m of water, and due to site factors such as residence tirne, and lag time in the redistribution of sediment in deeper lakes, it is possible that older sediments are closer to the surface here than at the other sites, as a result of lower rates of sedimentation. FIGURE 4.5. Kirk Lake, Alert, Nunavut. (a) The distribution of spheroidal carbonaceous black particIes (SPCBK) is shown as a proportion of the total combustion particle occurrence. represented by the samples analysed from the Kirk Lake core. (b) The relative abundance of the charcoal particle distribution with depth (cm) is shown. 1shadcd asis denotes O value

4 6 8 10 Relative abundance (%)

1 shaded ask denotes O value

4 6 Relative abundance (%) FIGURE 4.6. Lower Dumbell Lake, Alert, Nunavut. Histogram showing the percentage relative abundance of soot type and charcoal particles with depth (cm). j n charcoal I

Relative abundance (Oh)

shadcd asis denotcs O value

O+ not analyscd 3.6. Discussion

4.6.1. Partide types

Inclusion of data from the earlier study of Lower Dumbell Lake illustrates the

progression of the classification developed in Chapter 3 from its very basic orïgins, to the

more comples approach applied to Self Pond and Kirk Lake. In the case of Lower

Dumbell Lake, spheroidal particles ("soot") and charcoal type particles were the first

categories used. These sites were specifically investigated for the particle type described

in the literature as spherical. carbonaceous and btack, and associated with combustion of

coal and oil (Griffin & Goldberg, 1979, 198 1; Renberg & Wik, 1 b; Rose, 199 1).

The single most significant feature used in recognizing this type of particle is shape, whicli is commonly described as "spherical". This leads to the use of the terrn "spherical carbonaceous particle", or "SCP". tt should be noted, however, tliat while tnily spherical combustion particles occur and can be readily observed in reference materials prepared

from fossil fuel combustion particles, a range of somewhat Iess than spherical shapes is accepted by researcliers as belonging to this category (e-g. Griffin & Goldberg, l979:563

Fig. 1; Renberg & Wik, 1984:7 12, Fig. 1; Rose, 199128, Fig.4).

In the Alert samples, very few tmly spherical particles were found, the majority being more accurately described as spheroidal, eIiiptical or ovate. 1 included these particies in my counts, and to avoid confusion with what may be a more restrictive practice on the part of other researchers, have designated this category "spheroidal carbonaceous black" (abbreviated as SPCBK), at the point at which Self Pond and Kirk

Lake were analysed. 1 also increased the number of categories to include more roughly 146 rounded particles similar to those obtained €rom reference combustion sources using diesel oil as fùel. Tiiese rounded opaque particles were initially tenned "diesel- type". At the same time, additional categories were added for other opaque and non-opaque particles related to combustion, based on the work of McCrone & Delly (1973) and Fisher et al. (1978). These added categories were: "charcoal" (of al1 types, abbreviated as

"chtot"), non-black spheroidal particles (abbreviated as "NSPBK"), amorplious or irregular non-opaque particles, aciculate spheroids and coal-type rneaning non-combusted coal particles. Occasionally, other kinds of particIes were observed and noted, but were not included in the counts; for example, the occurrence of glassy rod-like shards, and the presence of diatoms. pollen and other unusual particles. A full description of the development of the classification was given in Chapter 3.

In the Self Pond samples, 6 particle types associated with combustion were observed and in Kirk Lake. 4 combustion particle types were found. suggesting a greater combustion source diversity for Self Pond, either in terms of sources of emissions, or of fuel.

The Kirk Lake result more likely represents the intensity of direct local activity, given the presence of the cabin and the large barbecue. The unusual nature of the sediments found in this and one other core were suggestive of coarse ash and rnay be directly related to these activities. Also the absence of two of the types seen in the Self

Pond core could support an argument for less exposure to diverse combustion sources.

The larger representation of charcoal may be a marker of anthropogenic burning as welI. 1.6.2. Combustion particle profiles

Al1 of the profiles exarnined for combustion particles at these two sites share some common features: 1) total particle relative abundance reaches a maximum, above and below which values are lower;

2) a smaller proportion of the total combustion particles occurs in the samples lower in the core than nearer the surface; and

3) the values for relative abundance of combustion particles at the surface esceed tkose for the lowest sample in the core that was analysed.

With respect to spheroidal carbonaceous black combustion particles (SPCBK). the profiles from the Self Pond and Kirk Lake sites appear very similar: in Self Pond, the

SPCBK niasimum lias a relative abundance of approsimately 14%, and occurs at a depth of 2.0 - 2-5 cm: while in Kirk Lake, the SPCBK maximum has a relative abundance of approsimately 13%. and is found at the depth of 1.5 - 2.0 cm. While we do not have conventional chronological or stratigraphie controls that enable us to detemine sedimentation rates or dates for these maxima, it is interesting to note the similarity in these two patterns of occurrence.

The differences are also of interest: greater combustion particle diversity implies greater source diversity with regard to particles deposited in Self Pond. Again this is most probably related to site factors, in the sense that Self Pond is soudi and slightly east of

Alert. and likely to be exposed to combustion emissions fiom power generation and open garbage burning, and afier January 1992, incineration, when winds are NNW. Gray

(1997) suggests that local combustion sources have at times been an issue. His account of 148 the interaction between the military base and the Atmospheric Environment Service

regarding the Bac kground Atmospheric Pollutant Monitoring installation (BAPMON), an

instrumented facility for monitoring atmospheric pollutants, indicated that in 1988 the

base agreed to conduct open buming at the dump when the winds are blowing out to sea

in order to avoid interference with the instrument readings. This change in management

practice could affect particle deposition at Self Pond. Studies by Renberg & Wik (1985)

and Rose (1998) have investigated the reIationship between spheroidal carbonaceous

particle (SCP) deposition and fuel consumption records? and found a pattern in the SCP

particle record in the sedirnent which tracks energy use reasonably well elsewhere. With

the adoption of modem fossil fuel-based te~hnology~there is a direct relationship between

levels of fuel consumption and population in extreme arctic environrnents. In the case of

Alert, this relationship can be sketched in a preliminary fashion from the work of Gray

( 1997) and Johnson (1WO), as shown in Table 4.1.

Looking at the non-spheroidal carbonaceous black component of the Self Pond

particle record known to be associated with rnixed burning, including spheroidal non- black (abbreviated as "SPNBK"), combustion amorplious opaque (abbreviated as

"cmamop") and combustion rnixed opaque and non-opaque (abbreviated as "cmmix") types (see Chapter 3), we see a peak in relative abundance in the region of 2.5 to 3.0 cm depth for these types (Figure 4.7.). This corresponds to the peak for total combustion particles (Figure 4.2.(b)). However, for cmamop and cmmix types, the peak is closer to

3.0 cm than to 2.5 cm, and these particles disappear from the record at 2.0 cm. If, as 1 suspect frorn the particle types, this pattern is related to mixed buming, such as the FIGURE 4.7. Self Pond, Alert, Ellesmere Island, Nunawt. The non-spheroidal carbonaceous black component of the particle record known to be associated with mixed buming includes spheroidal non-black (SPNBK), combustion arnorphous opaque (cmarnop) and combustion mixed opaque and non-opaque (cmrnix) types, with a peak in relative abundance in the region of 2.5 to 3.0 cm depth. n SPNBK

Ei cmamop

O 2 4 6 8 10 Relative abundance (%)

shadcd asis denotes O value 150 combustion of garbage, the absence of these types above 2.0 cm would give an inferred date of post-1988 for the sediment above, as this corresponds to the time at which measures were adopted to burn only when wind conditions would not carry emissions south (Gray, 1997; also Table 4.1). Also, given the record of a peak in the population of

Alert at 1986 (Gray, 1997), and the coincidence of the SPCBK peak at 2.5 as well, it would seem reasonable to infer a date of approsimately 1986-87 for the peak at 2.5 cm.

As the core was taken in 1992, the top of the core is given this date. Taking an approsimate date of 1987 for the 2.5 cm level, I estimate a crude rate of sedimentation of

0.4 cm il. '6 Projecting back in time and using this rate as an estimate, in order to reach pre-1950 levels, I would need a core approximately 16 cm deep- Turning to the Self Pond sediment record, the deepest sample 1 analysed for this study was at 9.5 cm, and when we look at the combustion particle profile, particles are still present at this depth, although at fairly low levels (- 3%), relative to the other samples analysed. Although a constant

Linear relationship between age of sediment and depth is unlikeIy, given possible compaction and redistribution within the iake following deposition, we can use the particle record to determine a more appropriate sampling and analytical strategy for Self

l6 This is very high in relation to values like those obtained by Zolitschka (1996) fiom Lake C2 at Taconite Lakes for esample, where values ranged fiom 0.18 mm y -' to 0.21 mm y". Lake C2 is a large la!!e (1.1 km'), and is more appropriately compared with Lower Dumbell Lake at Alert. In Lower Dumbell, the combustion profile peak for total combustion types occurs at 0.5 - 1.O cm, and setting this layer as 1987, would result in an estimated sedimentation rate of 1.O mm y -', still a much higher rate than that at Lake C2. However, unlike Lake C2, the terrain around Lower Dumbell Lake is subject to regular disturbance by heavy vehicles. Whether human activity can account for a 10-fold increase in sedimentation at Lower Dumbell cannot be assessed at this time. 151 TABLE 4.1. Chronology of combustion-related activities at CFB Alert, Ellesmere

Island (Based on accounts by ~ra~',I 997; and ~ohnson', 1990)

Date Activity I Capacity '* Fuel type Population ' (consumption) 1997 power generation 2 plants: Diesel 150 1x4 generators (2 on, 2 standby) + 1x2 generators (2 standby) 1988-1997 open buming Construction & packing wastes 1992 garbage al1 wastes incinerator except operationa1 construction & packing wastes 1986 27 1 (maximum) 1977 power generation 2 ausiliary units Diesel 200 added to 4 esisting generators 1968 fire - main power plant building burned 1950-1977 power generation, 4 diese1 diesel heating (including generators (for 1977 - water) 450,000 gal.) (CaterpiIlarB 2x500kW, 1x500 kW + Ix350kW)

2 950 founding of Alert oiI heaters, diesel ( aircrafi engine gasoline heaters, (estimated at generators 100 tondyear) 1950-1988 open garbage daily 1 burning 152 Pond. than our original assumption of exceedingly Iow sedimentation, and a total non-

biomass combustion particle record within 5 cm depth in the core. As indicated

previously, the other site at Alert for which we have obtained a profile of the relative

abundance of spherical black combustion particles is Lower Dumbell Lake (Doubleday et

al.. 1995). Conversion of these count values for soot and charcoal particle types to

percentage relative abundances based on total combustion particle count values, allows

construction of profiles which cmbe compared in general terms to those for Self Pond

and Kirk Lake, While the absoIute values themselves cannot be compared directly with

the other sites, the general characteristics of the profile appear similar: A maximum value

is reached, above and below which Ievels decline; the rnajority of the spherical

combustion particles occur in the top 2.5 cm; and the deepest sample which contains

spherical bIack combustion particles has lower levels than does the sample at the top of

the core. The ma~imumvalue for relative abundance of spherical combustion particles in

Lower Dumbell Lake (JPS-92-LDLH3C2) occurs at the 0.5 - 1.O cm depth, rather than

between 1.5 - 2.5 cm? as observed in the Self and Kirk cores.

Site factors are the most likely explmation for the differences between the combustion particle records for Lower Dumbell Lake, and for Self Pond and Kirk Lake.

Lower Dumbell Lake has an area of approximately 180 ha, compared with 37 and 100 ha

for Self Pond and Kirk Lake respectively. Also the core from Lower Dumbell was taken

in a much greater depth of water (20 m), compared with Self Pond (-1 m) and Kirk Lake

(2 m). The greater size of Lower Dumbell tvould lead me to expect a slower sedimentation rate, and chus a greater lag between capture by the Lake and deposition to 153 the sediment. Self Pond and Kirk Lake, as somewhat smaller Iakes, would respond more quickly in cornparison. However further work to define sedirnentation rates, with 210 Pb dating and in situ sediment traps would be helpful in comparing these quite different sites.

The elements of similarity, particularly the decline in partide levels at or just below the surface of the sediment, may be the more important message. Given that activity at CFB Alert has declined, in terms of numbers of personnel, budget and operational activities, since its peak in 1986 when the population was 271 (Gray, I997), it is possible that the decline in levels of combustion particles at the top of the cores from al1 three sites reflects this.

As shown in Table 4.1, which gives a sumrnary of combustion sources and events for the period foIlowing the founding of Alert, the general impression given is one of almost continuously producing point sources operating in support of activities at the base.

The two key types of emission-producing combustion facilities in regular operation are diesel-burning generators used to produce power, and open burning designed to eliminate waste. ParticIe types linked to these kinds of combustion were discussed in Chapter 3.

Given what we know about sedimentation rates in other, admittedly quite different lakes in Northern Ellesmere (Retelle, 1986; Toth & Leman, 1975; Bradley et al., 1996;

Ludlam, 1996; Hardy, 1996; Zolitschka, 1996), it would seem reasonabIe to assume a low rate of sedimentation compared with that of temperate regions, for Lower Dumbell. If so, the shalIowness of the combustion particle profile for Lower Durnbell Lake, would imply that the combustion particle record is dominated by relatively recent combustion. Even in 154 Self Pond where there is some evidence of combustion particles from the lowest level analpsed (Le. 9.5 - 10.0 cm)' levels near the top of the core are many times greater. The greater variety of combustion particle types in Self Pond is also suggestive of site-specific differences in combustion, more likely to be related to local sources. The nature of the partide record, particularly the dominance of the profile by "soot-type", suggests fossil fuel combustion, probably from human activity in the area.

HoweverSgiven that a decline in con~bustionpartide levels near the top of the sedirnent also appears in cores taken in other regions (Rose, 199 l), it cou1d also be argued that the sediment record reflects long-range transport, and therefore global background.

The most Likely interpretation is that the combustion particle records observed at AIert reflect both local and long-range influences.

4.7. Conclusions

The sites investigated near Alert do show evidence of combustion particle profiles that are similar in qualitative terms. The patterns at the Alert sites also resemble those tied to the dominance of fossil fueI-based human activities from other parts of the world,

In terms of paleolimnological understanding, the differences among combustion particle records at the sites documented at Alert underscore the importance of lakes as singular ecological and geographical entities?subject to similar landscape and meteorological forces, but processing those signals in site-specific ways. For esample,

Loiver Dumbell is a large lake that had significant ice cover and a small moat dunng the second week in July. 1992. It also has areas that are quite deep: cores were taken at 20 m 155 and 30 m From the surface. Combustion particle occurrence in relation to lake size and

depth may have the potential to reflect residence time and rates of deposition to the

sediment. As such combustion particles may be helpful spatial and temporal indicators,

particularly if used in conjunction witli other measures, such as S OP^.

In contrast, Kirk Lake and Self Pond present rather different profiles, in tems of

depth of the record and with regard to combustion particle types, suggesting local

influences resulting in variation, rather than a regional signal tending toward

hornogeneity. Differences in intrinsic site factors are of interest as well: both Kirk and

Self are smaller than Lower Dumbell, and both are subject to Iandscape and

anthropogenic influences which may lead to increased sedimentation and combustion

particle accuinulation.

Trends in patterns of combustion particle occurrence observed at Alert are strongly suggestive of a local fossil fiiel and otlier combustion origins, most probably related to the post-WWII period of local activity. With the addition of data from OP^ dating of these cores in the future, it may be possible to detemline much more authoritatively the extent to which combustion particle records in this region could be used as chronostratigraphic markers. Such dating would also assist in categoncally defining non-local particle types. However, even without supporting dates, the record of combustion particles does offer tangible evidence of human activity in this remote region. 156 CHAPTER 5

COMBUSTION INVENTORIES IN CONTEXT: CASE STUDIES RELATING

COMBUSTION PARTICLE OCCURRENCE TO OTHER

PALEOL[MNOLOGICAL RESEARCH AT HORSESHOE POND, ELLESMERE

ISLAND AND HAWK LAKE, KEEWATIN

5.1. Introduction

The results presented in this chapter represent the next step toward development of a nortli to south transect depicting the occurrence of combustion particles in an area of the Eastern Arctic. At Alert. 1 looked at combustion particle occurrence at three of the most northerly lakes in Canada (Chapter 4). The twu sites which are the focus of this chaptcr, Horseshoe Pond, Cape Herschel, Ellesmere Island, and Hawk Lake, Keewatin, comprise the central and longest portion of the transect, running from 78ON to 6j0N, approsimately 1650 km as a straight line distance (Figure 1.1).

5.2. Study Site Descriptions

5.2.1. Horseshoe Pond, Cape Herschel

In terrns of paleolirnnological research and contemporary ecological study, Cape

Herschel has been the subject of a long-running project of the Geological Survey of

Canada. Under the former leadership of W. Blake, Jr., the Cape Herschel Project has been the source of over 80 scientific contributions (Douglas et al. in press). Relatively few of these studies have been concerned with the issue of contaminants, in part because this 157 area- like the rest of the Arctic, was viewed as relatively pristine, until recently (McNeely

& Gummer, 1984). Also there are no year-round inhabitants and no economic or military

use which would make it suspect, such as the former Distant Early Warning Line Stations

or mines. However, between 1979 and 198 1, McNeely & Gummer collected surface

water, fiost rime and snowpack sarnples for chemical analysis for polycyclic aromatic hydrocarbons (PAH), organochlorines, chlorophenoxy herbicides, polychlorinated biphenyls (PCBs), metals and other parameters. One of the sites sampled was a "large pond on the south Coast of Rosse Bay, near Erik Harbor (3m a-s-l.)", at 78-63" N/074.71°

W. corresponding to Horseshoe Pond (Douglas, 1993). Some chemical tests were mn on the samples from this site, and data for physical parameters and major ions are reported for most of the samples (McNeely & Gummer, 1984). Analyses from other Cape Herschel sites, including one site near Horseshoe Pond indicate trace Ievels of some contarninants

(McNeely & Gummer, 1984). A subsequent unpublished investigation by J. Blais. cited by Douglas et al. (1994), found no evidence of anthropogenic lead isotopes in sediments from Cape Herschel.

The Cape Herschel site originally attracted my interest because of the pronounced change observed in the composition of the diatorn flora reported by Douglas et al. (1994).

This change can be surnmarized as a major shifi in composition of dominant taxa in ponds at Cape Kerschel occurring afier A.D. 1800, but probably earlier than the 19th century environmental changes usually associated with direct anthropogenic impacts. In consequence of the timing of the change, in part, Douglas et al. (1994) favour as an esplmation of climatic control, rather than anthropogenic pollution-related environmenta1 change.

Cape Herschel is Iocated on the east coast of Ellesmere Island (7g037'N,

74O42'W). This site was an active scientific research station between 1977 and the

199OYs,and the ponds continue to be studied every three years by J.P. Sm01 and M. S. V.

Douglas. In relation to the Alert sites (Chapter 4), the Cape Herschel sediment record was espected to show Little evidence of local human activity.

The bedrock in the area is Precarnbrian granite or granitic gneiss, and the overlying till is irreçuiarly distributed (McNeely & Gummer, 1984; Douglas, 1993;

Douglas et al. 1994). Cape Herschel is situated on the SE corner of the Johan Peninsula, to the south of Pim Island, and just beyond the northerly end of Baffin Bay. Here the passageway between Ellesmere Island and Greenland is very narrow, and the now nortliward-bound West Greenland current makes its rotation, joining southerly moving waters of the Baffin Current. This confluence creates a southward bound current that eventuaIly becomes the Labrador Current and which propels hundreds of icebergs into the

Atlantic each year. The adjacent Iandmasses of Ellesmere and Greenland have large placiers and the coasts of both islands have active glacier calving sites, although Ci

Greenland is the source of the most massive transfer of ice.

Horseshoe Pond has been described by Douglas (1 989, 1993) as a relatively large pond (approximately 4 ha in area), situated in calcareous tiIl. The site map (Figure 5.1 ) adapted from Douglas (1 99 1) and McNeely & Gummer (1 984) shows Horseshoe Pond on a peninsula between Erik Harbour and Smith Sound, less than 0.5 km fiom the coast. It is very close to sea level, the elevation being reported as 3 m a.s.1. The name ccHorseshoe FIGURE 5.1 Site map of Horseshoe Pond: Cape Herschel, Ellesmere Island, Nunavut. (Adapted from McNeely & Gummer, 1984; and M. S. V. Douglas, 1993.) Rosse Bay

Smith Sound 160 Pond", is informal, and refers to the shape of the pond. The reported depth of the pond is

50 cm (Douglas, 1993): and the drainage area is further descnbed by Douglas as: "rocky

rubble ...with a relatively high proportion of calcareous glacial/marine till. Some grassy

areas and rnossy banks comprise the vegetation." The presence of a number of bird

species, including snowgeese, red-throated Ioons and gulls on the banks and on the

islands in Horseshoe Pond, is also noted by Douglas.

The sediment 1 used was from Horseshoe Pond BS-78-26 Core 17. It is described by Douglas (1993) as follows: "13 cm; very wet; very organic; at 7-8 cm, transition from brown sediments (top sediments) to red brown (Iower llalf) sedirnent colour." These observations are supported by values for loss on ignition (LOI) that are above 50% for the entire core, and greater than 60% for the top 4 cm. The highest LOI value, 73.4%, occurs at the surface of the core. For comparative purposes, it should be noted that LOI values for anotlier Cape Herschel site, Ellison Lake, do not esceed 16%, and this maximum is reached at a depth of 4 cm down the core (Douglas, 1993). The zone of maximum LOI. is also believed to be the region of maximum "O Pb in the Horseshoe Pond core, with background reached at approximately 5 cm down core.

The sedimentation rate for Horseshoe Pond can be estimated, assuming a constant rate, and using the basal radiocarbon date from a second, longer Horseshoe Pond core, at about 30 yearslcm (Douglas, 1993), or 0.3 mm y-'. This would suggest a date of some 150 years earlier than 1978, or ca 1830 as a possible date at which the slope of the curve for

OP^ abruptly changes direction, and approaches background Ievels.

Using OP^ decay rates (Srnol& Douglas, unpublished data) plotted with depth FIGURE 5.2 Horseshoe Pond, Ellesmere Island, Nunavut. Profile of the estimated age of sediments frorn Horseshoe Pond Core 17 (BS-78-26) using '''~b decay rates plotted with depth (cm). (Smol & Douglas, unpublished data). Horseshoe Pond Core 17 (6s-78-26)

Year Depth (210 Pb estimated date)

J O 0.05 0.1 0.1 5 210 Pb concentration in Bqlg (cm), and half life decay rates, the point at which the decay rate plummets which is

usually taken to indicate leveis approaching background, appears to be more recent,

perhaps as recent as 19 12 (Figure 5.2). This would suggest a crude sedimentation rate of

approximately 1.0 mm y''. However, this is unlikely to be valid, given that OP^ fluxes to

the Arctic are known to be much lower, that sedimentation rates are also very low, due to

clirnatic constraints, and detection limits are likely to be reached before background

(Hermanson, 199 1; J.P. Smol, pers. comm.). This preliminary analysis of the OP^ data

without the benefit of other data. such as "'CS, that could be used to confirm

interpretation, should be treated as suggestive rather than definitive, as to the dates

proposed. Given the productive nature of this pond as shown by the high LOI values, bird

life and moss growth (Douglas, 1993), a higher estimate for recent rates of accumulation

of sediment as a function of higher levels of organic matter resiilting from biological

activity at Horseshoe Pond might be expected. Also, compaction would reduce

sedimentation rate values with greater depth in the core.

5.2.2. Hawk Lake, Keewatin

Hawk Lake (Figure 5.3) is located on the West Coast of Hudson Bay (63O38'N,

90°40' W). It is situated on the Precarnbrian Shield and has an area of 24.3 ha, and a

maximum depth of 4 m (Muir et al., 1995). This lake is one of a large set of northem

lakes that have been analysed for a variety of contaminants, including polycyclic aromatic

hydrocarbons (PAHs), organochlorine compounds, some metals and radioactivity

(Lockhart et al., 1993; Muir et al., 1995; Lockhart, 1995; Gregor et al., 1998).

Situated some 1650 km north of Winnipeg, Manitoba, Hawk Lake is 40 km north FIGURE 5.3. Site map of Hawk Lake. Keewatin, Nunavut. (Adapted from Welch, 1985 and Muir. 199 1.)

164 of the harnlet of Chesterfield Inlet, Keewatin. Other comunities located in the region include Rankin Inlet 120 km south, and Baker Lake, some 200 km West southwest of the lake. Relative to Cape Herschel, Hawk Lake lies approximately midway between

Horseshoe Pond, Cape Herschel, and Winnipeg. Treeline is located approximately 350 km to the southwest, at its most proxirnate (Welch, 1985).

Hawk Lake was selected for this study as a resuIt of encouragement by G.

Brunskill and L. Lockhart who were investigating patterns of PAH occurrence in remote lakes. While other arctic lakes were also subsampled for my study, the decision was made to focus on Hawk Lake as a result of data reported by Welch et al. (1 99 l), who found that a brown snow event deposited an estimated 1.84 kgha of particulate mass in the region.

Their analyses showed that the dust contained traces of chemicals, combustion products, organic matter and mineral dusts, which was interpreted as providing evidence of an

Asian origin for the event. The sampling of this event was fortuitous in that the investigators were at the site in order to obtain lake sediment cores, including the one from Hawk Lake that was the source of the samples that 1 analysed for combustion particles in this study. 1 was especially interested in the finding that combustion particles attributed to coaI buming were identified in the sample, and also in the discussion of previous similar occurrences Welch et al. (199 1). It has been suggested that, given estimates of the sedimentation rate for Hawk Lake of 55.1 g m -', based on 2'0~b rneasurements, a single such event could be expected to contribute between 2.7 and 27 percent of the total mua1 loading of the sum of PAHs found in the surface sedirnent of the lake (Welch et al., 1991). 165 On the basis of measurements of the concentration of rnercury in the sediments of

Hawk Lake and OP^ dating, Lockhart (1995) has estimatzd fluxes of mercury in the

surface slice at 5 ug/rn2iy compared with 0.6 at the bottom of the core. This

represents a five fold increase from values prior to A.D. 1750 (extrapolated date) to 1985

("Opb), or a doubling time slightly greater than a century (Lochart, 1995).

Muir et al. (1 995) esamined the distribution of organochlorine compounds in

sediments from Hawk and seven other lakes, extending from northwestern Ontario to

Ellesmere Island. They found sixteen organoclilorines. including DDT and toxaphene, at

a11 sites sampled. They also observed PCBs in the surface slices from these lakes. in terms of spatial trends, the highest values were reported for the most southerly sites, L382 and L375. and the lowest values for the most northerly, Lake Hazen and Buchanan Lake.

Not all organochlorines were found to have the same gradient with latitude. For esample,

Hawk Lake and one other lake had toxaphene, dieldrin and total chlordane values that were higher that those from northwestern Ontario and Lake Hazen (Muir et al., 1995).

Also the sum of the chlorobenzenes in the surface sediment samples was higher in the north than in the south.

In terms of temporal distribution patterns, Muir et al. (1995) found that the surface slices. that is the most recently deposited sediment in Hawk and other lakes, had the highest levels of organochlorines in each of the cores. In contrast, the rnost recent peak f0rp.p ' -DDT at Hawk Lake was found in slice 3, corresponding to the peak for OP^

(Lockhart et al. 1993). The peak for PAH occurred in slice 4, both well below the surface sediment (See Table 5.1, based on Lockhart et al., 1993; Muir et al., 1995). 5.3. Methods

5.3.1. Sampling

The Horseshoe Pond core (BS- 78-26 Core 17) was taken by Dr. W, Blake, Jr. of

the Geological Survey of Canada in 1978, as described in Douglas (1993). In surnrnary,

the core was obtained as frozen sediment and preserved as such until thawed for analysis

at Queen7sUniversity. 1took subsamples from this core, which were subsequently fieeze

dried by Dr, R, MchTeely,of the Geological Survey of Canada.

The Hawk Lake core (85-HLA) was one of many obtained from a suite of arctic

iakes by Drs- BrunskiIl, Lockhart, Muir and Welch, of the Freshwater Institute,

Department of Fisheries and Oceans, in 1985 for analysis of organochlorine, metals and

polycyclic aromatic hydrocarbons. 1 obtained subsamples for Hawk Lake in the form of

previously freeze-dried material.

Processing was done according to the digestion process developed by Rose

(1 994): taking care to avoid contamination, by using covered containers, glove boses and

clean air cabinets. The digestion was sIightly modified by omitting the step requiring

hydrofluonc acid, as discussed previously. FolIowing cornpletion of the digestion

process, 100.0 ul aliquots of a suspension of the sample were placed on clean coverslips

and dried for 12 hours. Slides were then made in a Class 100 clean cabinet, using H~X"

or FJaphra..x@as a mountant. Four replicates were made from each sample. This process was as described in detail in Chapter 4. 167 TBLE5.1: HAWK LAKE, KEEWATIN, NUNAWT. SEDIMENT SLICES, WTH DEPTH IN CORE (CM) AND MEDIAN AGE OF SLICE, SHOWING LEVELS OF POLYCYCLIC AROMATIC HYDROCARBONS (PAH) AND MERCURY.

lice' Depth Median ~~e'PAH (nglg).' Hg(n?Zk)' (cm)

Sources: '-~ockhartet al., (1 993), '~uiret al., (1 999, 3~ockhart(1995)

Note: Ages for slices 1-6 are from Muir et al., 1995. Ages for slices 8- 15 are read from graphs in Lockhart et al., 1995. Dates earlier than 1850 were extrapolated from plots for post-1850 Pb710, by Lockhart et al. Values for PAH and for lead are as read from graphs in Lockhart et al., (1993). * no date given ** mavimum value measured * * * cLmini-maxum"or secondary maximum value measured 5.3.2. Microscopical methods

Counts were made using a Reichert Research Microscope wïth transmitted and

indirect lighting, and equipped with polarizing filters. Counts were done of the complete

area of the coverslip, usually at a magnification of 4OOX, with the use of higher

magnification as required. The methods are as described in greater detail in Chapter 4.

5.3.3. Analytical and statistical methods.

The particles obsecved were first classified as to type, according to the working

classification established in Chapter 3, then enurnerated by category, following the same procedure as in the case of the Alert samples. However, in addition, al1 combustion particles observed were classified according to size using a British Standard graticule, according to the procedure described in Chapter 3,

For al1 sites. completed counts were entered into a database. For subsamples that deviated from 0.1 g dry cveight of sediment pnor to processing, due to factors discussed in Chapter 4, the raw count values were adjusted to the standard sample mass, converted to proportions and then to percentages. These values were then rounded, most ofien to the nearest integer, but depending on the levels observed and other considerations, as many as two decirnal places were retained in some instances, in order to emphasize relative abundance. Histograms were then prepared to show relative abundance of particles of al1 types observed compared to depth in the core, and to show the distribution of various particle types in the core as a whole and in relation to the total number of combustion particles observed. Histograms were also used to explore the particle size distributions in both the Horseshoe Pond and the Hawk Lake cases. 169 It should be noted that the two sets ofthree figures each for partide size class

distributions for Horseshoe Pond and Hatvk Lake are constmcted so that the maximum

particle diameter lies closest to the origin of the graph. This ordering reflects the relative

relationship of the size classes, based on the theoretical inverse relationship between

particle diarneter and transport potential, under uniform conditions, implying no wind

(Chapters 2 and 3).

5.4. Results

5.4.1. Descriptions of combustion particles from Horseshoe Pond, Cape Herschel

The following particle types were observed in the Horseshoe Pond core:

1. spheroidal carbonaceous particles

2. cenospheres

3. non-black spheroidal particles

4. pleurospheres

5. charcoal particles

5. a blochy

5. b. lath-shaped

6. opaque combustion particles

6. a. opaque angular

6. b. arnorphous

6. c. rounded

7. coal-type particles

Classes 1 to 6 in the list above are clearly associated with combustion, but class 7 .170 is excluded from combustion particle totals, even though unburned coal cmbe found in some post-combustion coal fly ash samples (McCrone, 1973).

In order to explore the relative abundance of combustion particles according to particle type and size class in Horseshoe Pond, a histograrn was constructed based on al1 combustion particles observed (Figure 5.4 (a)). To standardize particle classes between sites, values for al1 charcoal types were combined into a super-category, termed "total cliarcoai" (abbreviated as "chtot"). Similarly, the generic opaque combustion particle types were combined into a super-category termed "total combustion opaque" and abbreviated as "cmtot", when categories were summed, and "combustion generic"

(abbreviated as "cmgen"), when the primary type was also the counting category (Figure

5.4(b)). This was the case when only amorphous opaque combustion particles, not assignable to other specified categories; were observed.

From the distribution of al1 types of combustion particles in the Horseshoe Pond samples examined (shown in Figure 5.4. (b)), total charcoal particles can be seen to be the largest contributor, representing about 60% of the total. Spheroidal carbonaceous bIack particles contribute approximately 22%, followed by "total combustion" ("cmtot"), a supercategory created by surnming the contributions of amorplious opaque, amorphous angular and amorphous rounded types.

In terms of temporal distribution? combustion particles in the top four samples from the sediment surface down the core, plus two additional samples, one at 8 cm and the other at 12 cm, were analysed, and the particles were typed, counted and sized. This was done in order to look for any recent change, meaning within FIGURE 5. 4,Horseshoe Pond, Cape Herschel, Ellesmere Island, Nunavut. (a) Histogram showing percentage relative abundance for al1 combustion particles observed by type. (b) Histogram showing percentage relative abundance for al1 combustion particles observed by supercategories including "total combustion opaque" (ibcmtot"), combustion generic" ("cmgen"). and total charcoal" (abbreviated as ccchtot"). Further discussion of combustion partide classification and categorization is given in Chapter 2. combustion particle type

SPCBK Csph SPNBK Psph chtot cmtot cmtot combustion particle type 172 the Iast 150 years approxirnately; and to compare IeveIs approaching the surface of the

sediment tvith Ievels at depth, representing earlier periods of time. In the case of

Horseshoe Pond, a histogram constructed from the total combustion particles counted

shows a definite maximum in the top Iayer, comprising some 45% of al1 of the particles

ofall types found (Figure 5.5 (a)). Levels then decline abruptly to approximately 10% in

the second sample. The third sample, corresponding to a depth of 3 to 4 cm, shows an

increase in total particle load to a secondary maximum, with the relative abundance of total combustion particles almost doubling to just less than 20%. Levels are lower in the remaining 3 sarnples analysed. A comparison of the sarnple from the deepest layer (12 cm) with the sediment surface layer indicates that levels of combustion have increased just over 10-fold. The sample from 8 cm has a relative abundance of combustion particles approsimately midway between that of the bottom and the top, at about 8%.

The temporal distribution of the spheroidal carbonaceous bhck particles

(SPCBK), as depicted in Figure 5.5 (b)? is similar to that of the profiIe for al1 combustion particies, in that particle occurrence in the bottorn sample is considerably lower than layers nearer the surface. The second slice shows a reduction in the relative abundance of

SPCBK in comparison with the top slice, followed by an increase in the third slice, as is the case for relative abundance of combustion particles of a11 types (Figure 5.5 (a)). The rnost noticeable contrast between the profiles for total combustion particles and for

SPCBK is that in the case of the latter, the level of relative abundance at the surface is matched by that of the third Iayer, rather than presenting a clear-cut maximum at the top.

For the total charcoal particle distribution shown in Figure 5.6, as a percentage of FIGURE 5.5. Horseshoe Pond, Cape Herschel, Ellesmere Island, Nunavut. (a) Histogram showing changes in relative abundance (%) for al1 combustion particles recorded, expressed as a percentage relative abundance with depth (cm). (b). Histogram showing changes in relative abundance with depth in the core (cm) as a proxy for changes in the temporal distribution of spheroidal carbonaceous black particles (SPCBK) with depth, expressed as a percentage relative abundance. 10 20 30 40 Relative abundance of al1 types of combustion particles (%)

unot analyseci

5 10 15 20 25 30 35 40 45 56 Relative abundance of SPCBK type combustion particles (%) 0-0 174 the total combustion particle count, the profile shows the highest levels at the top of the

core, with approsimately 24% of the charcoal occurrence in the sediment surface layer.

As in the case of the SPCBK type particles, the second sarnple at 2 - 3 cm has a smaller

proportion of the total charcoal present.

Figures 5.7 (a) to (c) show the result of the particle size class analysis. Figure 5.7.

(a) shows the size distribution pattern of the combustion particles enumerated in the

Horseshoe Pond core sarnples as a uni-modal distribution with a median class of 3.5.

However, when the particle size distributions for the charcoal particles as a super-group

(Figure 5.7.(b)), and for the SPCBK type (Figure 5.7.(c)), are examined, the MO components display rather different size distributions. The general histogram for al1 types

5.6.(a), evidently obscures this, and it appears that the distribution is in fact bimodal.

5.4.2. Descriptions of combustion particles from Hawk Lake, Keewatin

The following particle types were observed in the Hawk Lake core:

1. spheroidal carbonaceous particles

2. non-black spheroidal particles

3. pleurospheres

4. charcoal particles

5. opaque combustion particles

5. a, opaque angular

5. b. arnorphous

5. c. rounded FIGURE 5.6. Horseshoe Pond, Cape Herschel, Ellesmere Island, Nunavut. Relative abundance of total charcoal particles enumerated with depth (cm), as a percentage of total combustion particles enumerated. O 10 20 30 40 50 Relative abundance of charcoal particles % FiDgure 5.7.(a), (b) and (c) Horseshoe Pond, Cape Herschel, Ellesmere Island, Nunavut. Results of the particle size class analysis for Horseshoe Pond. (a) Histogram of size class distribution of total combustion particles enumerated. Size distribution pattern of al1 the combustion particles enumerated in the Horseshoe Pond core samples for al1 types. (b) Relative abundance of charcoal by size class as a percentage of the total combustion particles enumerated. (c) Relative abundance of spheroidal black carbonaceous partides (SPCBK) as a percentage of the total combustion particles enumerated. Size class midpoints and extremes

al Oc (CI -0 C n3 (CI al .-> -CCu 0 [lr

>7 6-5 5.5 4.5 3.5 2.5 1.5 cl Size class rnidpoints and extremes

Size class midpoints and extremes 6. combustion amorphous mixed, opaquelnon-opaque

7. coal-type particles

Particles belonging to classes one to six were enurnerated. Histograms of the total combustion particle content in the sarnples analysed are presented in Figure 5.8. Figure

5.8.(a) shows the relative abundance of combustion particles by type as a percentage of the total in al1 classes, with subclasses broken down for class 5, the opaque combustion particles. Figure 5.8.(b) presents the same information, but for ease of cornparison with the Horseshoe Pond result in Figure 5.4.(a) shows the sum of al1 subclasses of class 5, opaque combustion particles.

It is very clear that the single most important type of combustion particle observed in the Hawk Lake samples is charcoal: approximately 58% of the total number of particles observed consisted of charcoal of al1 types (Figure 5.8.(a) and (b)). The second largest category, in terms of relative abundance, is that of combustion particles belonging to the combustion amorphous opaque class, termed generic combustion and abbreviated in the diagram as "cmgen". This 'Super-group" consists of the sum of values for combustion angular opaque, combustion rounded and combustion mixed opaquehon- opaque shorvn in Figure 5.8.(a), and represents approximately 17% of the total number of particles observed in the Hawk Lake sarnples. The third most abundant type of opaque combustion particle observed is the spheroidal black carbonaceous particle type

(SPCBK). However, pleurosphere type (Psph) and non-opaque, spheroidal non-black type

(SPNBK), together are twïce as abundant. FIGURE 5.8. Hawk Lake, Keewatin, Nunavut. Histograms of the total combustion particie content in the samples analysed are presented. Figure 5.8.(a) shows the relative abundance of combustion particles by type as a percentage of the total in a11 classes, with subclasses broken down for ciass 5, the opaque combustion particles. Figure 5.8.(b) presents the same information, but for ease of cornparison with the Horseshoe Pond result in Figure 5.4.(a) shows the sum of al1 subclasses of class 5, opaque combustion particles. SPCBK Csph SPNBK Psph chtot cmgen crnanop crnRN cmmk corn bustion particle type

Key SPCBK - spheroidal, carbonaceous, black type Csph - cenosphere type SPNBK - spheroidal, non-black type Psph - pleurosphere type chtot - totai charcoal of all types cmgen - combustion generic (black) type cmanop - combustion angular opaque type cmRN - combustion rounded opaque type cmmix - combustion mixed opaque non-opaque type

SPCBK Csph SPNBK Psph chtot cmtot combustion particle types (b) 179 Another interesting feature of the distribution of total combustion particles in the core with depth (Figure 5.9), is occurrence of a distinct minimum in slice nurnber 7, at 7.8 to 9.1 cm Below this level, the relative abundance of combustion particles again increases sharply to just over 6% in slice 8, which corresponds to a depth of 9.6 cm, representing the midpoint of the slice, and to a date of pre- 1900 (Muir et al. Z 99 1). The relative abundance of combustion particles again declines gently to a second minimum in slice

1 1, corresponding to a depth of 13 to 14.3 cm, which has been given an estimated age of ca. 1850 based on estrapolation from OP^ dates (Lockhart et al. 1993). The relative abundance again increases in slice 12, almost doubling. The last sample 1 analysed in this core is from slice 15, corresponding to a sediment interval of 18.3 to 19.5 cm depth. This

IeveI has been given an estimated date of pre-1800. It shows the presence of combustion particles, at levels similar to those in slice Il, but locver than the minimum at slice 7.

The overall pattern observed in the Hawk Lake samples is one of much higher levels of combustion particles of al1 types in the more recent sedimsnts (Figure 5.9), with a maximum occumng at a depth of approximately 3 cm, and corresponding to a date of

-1 961 (Muir et al. 1995).

Of the total charcoal observed in samples from the Hawk Lake core (Figure

5.1 O.(b)), 64% occurred at a depth from 1.3 to 6.5 cm in the core. According to the dates assigned by Muir et al. (1995) and summarized in Table 5.2, the sediments have a median age of 1927 at a depth of approximately 6.5 cm.

Figure 5.10.(a) indicates the distribution of spheroidal carbonaceous black particles (SPCBK) that are generally believed to be associated with anthropogenic FIGURE 5.9. Hawk Lake, Keewatin, Nunavut. Histogam showing the distribution of al1 combustion particles of al1 types found in the Hawk Lake sediment core samples with depth (cm), as a percentage of the total particles enumerated.

181 combustion. The relative abundance of these opaque spheroidal parti cles in relation to the total number of combustion particles enumerated in the Hawk Lake samples displays a somewhat sirnilar pattern to the distribution with depth observed for total combustion particles.

First, however, it should be noted that levels of SPCBK are qaiite low in general, as reflected in the change in the horizontal scale of Figure 5.10.(a) in cornparison with

Figures 5.9 and j.lO.(b). Again a pronounced minimum occurs in slice 7 (no SPCBK type particles are observed). corresponding to an interval depth of 7.8 to 9-1 cm The profile of

SPCBK then differs from that for al1 combustion particle types: levels in slice 8 increase, but show a further increase in slice 9, at a depth of 10.4 to 1 1.7 cm. niis is the last level from which SPCBK type particles have been observed in the Hawk Lake sarnples: they are not detected in slices 10 to 12, nor in 15.

Given the dominance ofcharcoal in the sediment record of combustion particle types from Hawk Lake, it is not surprising that the profile of relative abundance of al1 charcoal (Figure 5.1 O.(b)) as a percentage of al1 combustion particle types would strongly resemble the profile for a11 types (Figure 5.9.). For charcoal type particles, a maximum is reached in slice 3, at the interval from 2.6 to 3.9 cm down core. Over 40% of the charcoal is found in the top 6 cm of the core, and occurs to varying degrees in al1 12 sarnples examined. The minimum observed occurs in slice 1 1, at 13 to 14.3 cmdeep, with higher levels observed Iower in the core, in slices 12 and 15.

The contribution of the generic combustion total (cmtot) includes the opaque and non-opaque generic particle types and is shown as a percentage of the total of al1 FIGURE 5.10. Hawk Lake, Keewatin, Nunavut. (a) Distribution of SPCBK type particles with depth in the core (cm): as a percentage of total combustion particles enumerated. Note that the scale of the horizontal avis has been expanded for emphasis. (b) Distribution of al1 charcoal type particles with depth (cm), in the core as a percentage of total combustion particles enumerated for al1 types. Note that the horizonta1 scale is reduced from that in (a). 1shaded axis denotes O value not dysed

1 1 -5 2 relative abundance (%)

not analyseci

O 2 4 6 8 10 relative abundance (%) 183 combustion particles enumerated (Figure 5.1 1.(a)). For comparative purposes, the opaque types of generic combustion particles are then extracted to create Figure 5.1 1.(b). Given that this process of association of related types creates a significant overlap between the groups of particles included in each figure, it is not surprising that the figures resemble one another. Perhaps the more interesting element is the difference between the two, attributed primarily to the exclusion of the mised opaque-non-opaque particles, and is expressed in Figure 5. 11.(a) and 5.1 1.(b) as a major difference between relative abundance given for slice 6 at 6.5 to 7.8 cm. This slice corresponds to a proposed date of

L 908 (Muir et al. 1995).

Figures 5.12.(a), (b) and (c). display histograms showing the size class distributions of al1 combustion particles from the Hawk Lake samples, of al1 types enumerated, of total charcoal particles and of SPCBK type particles, respectively. As was observed with regard to the Horseshoe Pond size class distribution for al1 combustion particles enumerated (Figure 5.7.(a), (b) and (c)), the first of these plots suggests a sIightIy skewed uni-modal distribution. However, in the case of the distribution of total charcoal by size, a more pronounced skew appears. FinalIy in Figure 5.1 2.(c), an even narrower distribution, skewed in the opposite direction to that of the charcoal, is produced by SPCBK type particles. Comparison of the three figures is instructive, as what appears to be uni-modal slightly skewed distribution unfolds into two very dissimilar categories of particle types. The largest size class is placed nearest the origin, reflecting the relative relationship for the size classes, based on the theoretical inverse relationship between particle diarneter and transport potential, under uniform conditions, meaning no wind. FIGURE 5.1 1. Hawk Lake, Keewatin, Nunavut. (a) Distribution of ai classes of generic combustion particle types (crntot=cn~gen+cmmop+cmmix), with depth (cm) as a percentage of total combustion particles enumerated. (b) Distribution of the sum of a11 classes of opaque combustion particle types (cmoptot=cmtot-cmrnix), with depth as a percentage of total combustion particles enumerated. - - - pp- 1 shaded axis denotes O value not adysed

O 1 2 3 4 5 6 7 relative abundance (%)

Oshaded a..s denotes O value + not analyseci

2 3 4 5 relative a bundance (%) FIGURE 5.12. Hawk Lake, Keewatin, Nunavut. Results of the particle size class analysis. Histogam of size class distribution of total combustion particles enurnerated. (a) Size distribution pattern of dlthe combustion particles enurnerated in the Hawk Lake core samples for al1 types. (b) Relative abundance of charcoal by size class distribution of the total combustion particles enumerated. (c) Relative abundance of spheroidal black carbonaceous particles (SPCBK) as a percentage of the total combustion particles enumerated. 6.5 5.5 4.5 3.5 2.5 1.5 Particle size classes - midpoints and extremes

6.5 5.5 4.5 3.5 2.5 1.5 Particle size classes - midpoints and extremes 5.5. Discussion

Horseshoe Pond and Hawk Lake represent dissimilar sites, in terms of latitude, size, and depth. Yet there are similarities: sediments fiom both have relatively high levels of organic matter, and the inputs of combustion particles to both sites appear to be dominated by charcoal. Both sites reveal evidence of abrupt changes in their sediment records, through diatom research (Douglas, 1993; Douglas et al., 1994) and geochemistry

(Muir et al., 1995; Lockhart, 1993). Combustion particle inventories, as reflected in the histograms of particle distribution with depth, and in the composition and size distribution of the "particle" rain, contribute to understanding environmental change.

In general, the samples from Horseshoe Pond reflect the pattern described previously: combustion particles appear in the core at relatively low levels earlier in the core. increasing to a masimum near the surface. At Horseshoe Pond, 1 recorded a combustion particle maximum in the top centimeter of the core which accounts for approximately 45% of the total combustion particle load for the sis samples analysed.

This corresponds to the position of the maximum value (73.4%) for the profile of loss on ignition in this core obtained by Douglas (1993). Sediment samples fiom farther down in the core, representing earlier time periods, contributes a much smaller proportion of the total particles found in the samples analyzed, as expected (Figure 5.4 (a)). Work by others

(Griffin & Goldberg, 1979, Wik & Renberg, 1985; Rose, 1991) has repeatedly produced this result. What is interesting however, is that based on a preliminary analysis of

Horseshoe Pond 2'0~bdata core provided by Sm01 and Douglas (unpublished, see

Appendix 5.3), levels of '"~b have alrnost reached background at 5.5 cm down the core, 187 at an estimated date of 19 12. This corresponds roughly to the transition between early and more recent levels of particle deposition, inferred from the modest proportion of the particle record contributed by older sediments. In order to define the temporal changes in the combustion particle record more clearly, now that "Opb dates are available, higher resolution is required and additional analysis are needed".

In terrns of particle types, it can be seen from Figure 5.6.(a) that total charcoal appears to achieve a distinct maximum in the top layer, drops to a minimum in the second sample, then rises a few percent in each of the next two samples. At four centimeters, approximately 10% of the total combustion particles occur the form of charcoal. Al1 samples esarnined contained charcoal (Figure 5.6.).

Spheroidal carbonaceous black particles are found in small proportions in al1 of the samples esamined; the Iowest levels occurring at the bottom of the core (MN),and increasing to 5% at 8 cm (Figure 5.5.(b)). The proportion of SPCBK type particles then dedines at 4 cm to approsimately 3%, increases to 8% in the sample above, and then declines to - 3% at 2 cm just below the surface. At the surface, SPCBK constitute 8% of

17 The diatom record shows a number of changes between samples at 4-8 cm. For example, in the core at the 3-5 cm interval, Douglas (1993) notes an increase in abundance of several diatop taxa, including Achnanthes minztitissima, Achnanthes spp., Cocconeis placentula, Denticda spp. and several Nilzschia spp. At the same depth a decline in Nmiiculata vztlpinn is reported. Cocconeisplacentztla is known to be epiphytic on mosses, and its appearance in the core may indicate the period of time at which the moss bank developed (Douglas, 1993). Other less marked diatom shifts noted by Douglas (1 993) incfude increases in Cyrnbella spp. (1 0 cm) and Navicula vulpina ( 8-4 cm). In terms of abrupt straigraphic transitions, it can be seem from the diatom profile for Horseshoe Pond (Douglas 1993), that one of the Fragilaria species, Fragilaria construens var. venter-, although never more than 10% of the relative abundance, achieves a distinct maximum at 6 cm, and has vanished by 4 cm. 188 the total combustion particle load in the core (see Figure 5.4(b)), not a large proportion in cornparison with charcoal (25%) as depicted in Figure 5.6. The "early" appearance of spheroidal opaque particles in the sediment record may have a number of explanations.

For esarnple, there was a coal mine at Disko which operated for several decades

(Schiener, 1976). Some Greenlandic sources have claimed a rnuch longer history of coal burning, and stem-powered sailing vessels burned coal, some of it taken on in

Greenland. Large arnounts of coal were also brought north and burned by the whalers, missionaries, traders and others, and indeed relatively recent vessels such as the Nnscopie cvhich travelled from Hudson Bay to Lancaster Sound in the 1940s also bumed coal (R.

Gilbert, pers. comm.). Tliese amounts would be insignificant from the point of view of a concern for poIlution, but that does not mean that such emissions would be without effect in a nutrient poor environment.

The particle size distributions for total combustion particles, charcoal particles and SPCBK type particies are shocvn in Figure 5.7.(a), (b) and (c), respectively. The total combustion particle size class distribution for Horseshoe Pond (Figure 5.743)) appears to be a slightly skewed unirnodal distribution, with a greater representation of particles in the srnaller size classes. However, the figures for charcoai and for SPCBK type particles look sornewhat different: charcoal particles appear to be almost normally distributed among the five inner bins, with a slight skew towards the smaller size classes, while

SPCBK type particles have a size cIass pattern that is both strongly skewed and concentrated in the lower half of the size class range.

1 believe this pattern of particle occurrence supports the interpretation that the 189 magnitude of change in particle deposition in the most recent layer of the core is significantly greater than at lower Ievels, corresponding to earlier penods. However, the combustion particle record appears to persist throughout the core, albeit at very low levels, and so this investigation would appear to lend support to the argument for a longer period of anthropogenic change discussed by Douglas (1993) and Douglas et al. (1994).

However caution is advisable in makinç further interpretations. due to the lirnited number of sarnples.

In order to understand possible sources, it is useful to look at natwal vectors.

Birds migrate long distances using prevailing winds, as do pollutants. Birds migrating to

Cape Herschel from wintering grounds in the south have essentially two options in tems of routes: either they travel the mid-North Arnerican fly-way, cross Hudson Bay and the lower Queen Elizabeth Islands. to arrive at the south Coast of Ellesmere, or they travel the

North Atlantic Davis Strait-Baffin Bay route. Of the two, the more easterly route may be more attractive, as it is shorter, more direct, and does not involve travel over extensive continental and inland waters which are much slower to open up in spring than the coastal marine areas like Davis Strait and Baffin Bay, which have the benefit of powerful ocean currents. Also it must be remernbered that not al1 marine areas are ice-covered in the

Eastern Arctic in winter. There are large areas of open water, termed polynyas, which are important for moderating local conditions and for sustaining marine wildlife. The North

Water, to the east of Cape Herschel, and Lancaster Sound, south of Ellesmere, are notable proximal esamples.

With regard to the role of wind currents and birds as biological agents of diatom 190 introduction at Cape Herschel, Douglas (1 993) presents a persuasive argument pointing to the role of long-distance atrnosphenc transport, both organismically facilitated, and unassisted, as a mechanism. In addition to the south-north migratory route used by many species of birds found in the Arctic, there is also the potential for atmosphenc transfer from the north to Cape Herschel, principally as passive atrnospheric transport in winter

(Gregor et al. eds., 1998).

In the case of the more southern Hawk Lake there is evidence of change in the sediment profile with respect to Ievels of rnercury, lead, organochlorines and polycyclic aromatic hydrocarbons (Muir et al., 1995; Lockhart et al., 1993; Lockhart, 1995). The record of polycyclic aromatic hydrocarbons (PAH) are of particular interest with respect to combustion particle occurrence. as combustion products frequently contain PAH, and fuels comnionly used to support anthropogenic combiistion also contain PAH. The identity of specific PAH has been observed to be related to fuel type and combustion process (Charles & Hites, 1987). The patterns of occurrence detected by Lockhart et al.

(1 993) have been described in more detail above, and can be summarized in general ternis as follows: for the sum of sixteen polycyclic aromatic hydrocarbons, a maximum is attained around 1950, with a decline above this to the surface of the sediment- Values for

PAH from the bottom of the core are lower than such values at the top. For mercury a long period of loading was observed, which was interpreted as pre-dating 1885. With respect to PAH, Hawk Lake was also shown to have a long history of PAH deposition, which was attributed to Iong range transport.

It should be noted that, unfortunately, no sample material was available for combustion particle analysis from the top slice of the Hawk Lake core due to consumption for other analyses, therefore; al1 combustion profiles presented here are from sediment slice two and deeper. However, the record of total combustion particle occurrence presented in Figure 5.8, indicates a maximum in slice 3, corresponding to a median slice depth of 3.2 cm The median age assigned to this slice in Muir et al. (1995) is

1961. It would seem reasonable to interpret the earliest date for this maximum as mid way between the median dates given by Muir et al. (1995) for this and the adjacent slice, or, approximately 1952. This would seem to be in general agreement with the published date for the PAH mauimum, and I would infer a correlation between the occurrence of the combustion particle rnaxinium and that of the measured value for the sum PAH mâxirnum.

Farther dom the core, Lockhart et al. (1993) identifies an early secondary sum

PAH maximum. which he extrapolates to a date of pre-1850. Frorn the published profiles. this corresponds to a core depth at or greater than slice 1 1, or a median sample depth of

14.3 cm down core (Figure 5.1 1) The combustion particle record for al1 particles observed, indicates a distinct secondary maximunl between 14.3 and 15.6 cm. This value contributes approsimately 4% of the total particle distribution in the core for al1 particle types, and is twice as high as the value from the lowest slice analysed, at 18.2 - 19.5 cm

Again, on a qualitative basis, the correspondence between the measured sum PAH profile and the counted total combustion particle record is positive, and 1would infer a relationship between the two profiles, that could be tested by subsequent work.

I observed an interesting discontinuity in the pattern of spheroidal carbonaceous 292 particles (SPCBK) in Hawk Lake: Rather than an initial appearance at low levels,

followed by a gradua1 increase up the core, there is an abrupt appearance corresponding to

a secondary maximum, in slice 9, followed by a sIight decline in slice 8. In slice 7, no

SPCBK type particles were detected, and above this, the classical profile with presence at

low levels, followed by fluctuating abundance, with a maximum observed in slice 3, and

a decline in slice two. Stronger inferences from this profile are constrained, as these

particles constitute less than 10% of the total combustion particles observed.

5.6 Conclusion

In terms of the possible applications of the combustion particle inventory

approacli to paleoecological interpretations of environmental change using lake

sediments, the case studies of Horseshoe Pond and Hawk Lake are encouraging. While

definitive statements are Iimited by gaps in infornlation concerning interpretation of dating and other key issues. investigation of combustion particle occurrence at these two

very different sites has supported the recognition of similarities in wide spread patterns of distribution? specifically the increase in loading at the sediment surface, corresponding to the inost recent period of deposition. Although levels of occurrence are too low to make expansive claims, the trends observed resemble those in other, more industriakzed areas.

In addition, where anomaIies have been found in a core, such as the early secondary peak in polycyclic aromatic hydrocarbons at Hawk Lake reported by Lockhart et al. (1 993), construction of a profile of relative abundance for combustion particle types and depth does indicate that a relationship between the PAH levels and the combustion 193 particles should be further investigated. Although much lower levels of particles are

observed at Horseshoe Pond than in the case of Hawk Lake, the sediment record of

combustion particle occurrence does provide evidence of a long history of particle

deposition. While the profile follows the general pattern of a significant increase at the

top of the core, there are suggestions of fluctuations that may also be of interest from a

climatic standpoint. The evidence of early occurrence of combustion particle transport

and of fluctuations in patterns of distribution of particle types also supports the findings of Douglas et al. (1994) with regard to signals of early environmental change.

1 believe these results confirm the merit of this approach to combustion particle classification and invento-. Further development and testing is required but, in my view, this approach has sliown itself deserving of suc11 an effort. 194 CHAPTER 6

COMBUSTION PARTICLE INVENTORIES AND PALEOENVIRONMENTAL

FUCCONSTRUCTION OF LONG-RANGE TRANSPORT INFLUENCES: A CASE

STUDY FROM THE BELCHER ISLANDS, NUNAVUT

6.1. Introduction

Of the many possible relationships of interest in terms of anthropogenic effects in arctic environrnents, long-range transport and sources are of particular interest. In order to regulate pollutants, we need to know what they are, and in order to control them effectively, we need to know from whence they corne. Based on the work by Griffin &

Goldberg (1979) that linked fuels and particle types, the forensic particle analysis of

McCrone & Delly (1 973), and the findings of correlations between combustion particles and pollutants (Charles & Hites, 1987; Rose & Juggins, 1994). 1 developed a hypothesis that information concerning Iong-range transport relevant to pollutants in the Arctic could be obtained by study in the distribution and occurrence of con~bustionparticles and other biogenic tracers (Doubleday, 1992). If so, in addition to providing information about depositional histories, and aiding in interpretation of sediment profiles developed using chemical analyses, conibustion particle studies might also provide an additional tracer for source identification. In order to explore the feasibility of pursuing this approach, it is advantageous to use a site for which wind patterns are well known at a regional scale, and where airborne particdate pollutants can be expected to occur, at least at low levels. The

Belcher Islands in Hudson Bay are one such possible site. 195 6.2. Sîudy Site Descriptions

The Belcher Islands are set of low-lying islands (QOOm. a-s-l.), to the noah of the junction of James Bay and Hudson Bay (Figure 6.1). They serve as the geographic marker

of the most southerly tip of Nunavut, the new territory comprising the Eastern Arctic, not

tvithstanding their location at 56ON, 79"W. The inclusion of the Belchers in the new

territory was the result of long-standing cultural and environmental affinities with the

High Arctic and the Inuit, and the fact that they were previously part of the Northwest

Territories.

The Belcher Islands are outcrops of the Circum Ungava Geosyncline (Dyke et al.,

1989) and were well-scoured by glaciation in the past, Ieaving what today is designated as

"rock" on a map of surficial geology (Dyke et al., 1989). Dredge and Cowan (1989) list the following rock types as occurring in the Belchers: oolitic jasper, siltstone, greywacke, and concretionary siltstones, which are characteristically dark coloured and readily identifiable. These have been found in the fonn of erratics in southwestern Ontario and as far west as Alberta, providing tracers for reconstruction of Laurentide glaciation and deglaciation (Dyke et al., 1989). Hermanson (1 990) reported the presence of basalt at one of his sites on the Belcher Islands. The BeIcliers are still experiencing post-glacial isostatic rebound, as evidenced by the presence of raised beach terraces, such as the one for which "Raised Beach Pond", was named, which are indicative of previous sea levels.

Today, this site is approximately 70 m. a.s.1,

The marine environment remains an important force in the ecology and climate of the Belcher Islands, in terrns of currents, ice regimes and biota (Sly, 1995; Rouse, 1991). FIGURE 6.1. Site location map of Raised Beach Pond, Pond 5 and Dry Pond, Belcher Islands, Hudson Bay, Nunavut. Sanikiluaq (North Camp)

Flaherty Island 197 In environmental terms, the latitude of the Belchers corresponds to treeline on the mainland, but the vegetation here is actually a tree-less mid arctic-tundra, The difference can be attributed to the moderating influences of Hudson Bay, which reduces temperatures significantly, on the order of 5-10', in cornparison with other mainland sites at the same latitude, due to the persistence of ice-cover in the Bay. In climatic terms, the

Belchers lie on the boundary between the dry subhumid (Ci) and the moist subhumid (Cz) climatic regions of Thomthwaite (National Atlas of Canada, 1990), attributable in part to the incursion of Atlantic air masses (Bryson, 1966).

The main settlement on the Belcher Islands is Sanikiluaq, Iocated near the north end of Flaherty Island. From Sanikiluaq it is approsimateIy 975 km to Hawk Lake,

Keewatin and 2935 km to AIert, Ellesmere Island. Toronto Iies some 1425 km south.

Sudbury, Ontario is approsimately I O88 km SS W, and FIin Flon, Manitoba is 13 87 km

WSW.

6.2.1. Raised Beach Pond

Raised Beach Pond (79 16'W' 56 34'N) is approximately 3 km WNW of the hamlet of Sanikiluaq. It is situated on a former beach, now at an elevation of approximately 70 m. This pond is described as large and shallow (approximately 20 cm deep), subject to seasonal drying due to evaporation, which causes it to lose a significant portion of its area dunng the summer (Douglas & Smol, field notes, unpublished).

Unpublished data from Moser et al. for loss on ignition give a mavimum value in excess of 30% at the surface, declining 7% in the first centimetre, 15% by 4 cm depth, and reaching a first minimum (at approximately 4%) at 8 cm depth. At 10 cm a very 198 slight increase is seen (to approximately 5%), declining to 3% at 13 cm. Biogenic silica is also reported by Moser et al. (unpublished), with a maximum value of 6% by weight at a depth of 2 cm, declining to 4% at 6 cm, and to 1% at 8 cm At the bottorn of the core a minimum of approxirnately 0.3% is reached.

Diatom analyses completed for the same core (Douglas, unpublished) indicate that at the top of the core a FI-agilat-iapinnatacomplex dominates the diatorn flora with a relative abundance of 60%. but that this is in fact a decline from conditions at the bottom, where it contributed 100%. Other species are observed at 8 cm including Achnatzfhes spp.. Nmiczrlntn spp. and hrirzschic~spp. At 4 cm, FI-ogilariapinnafa cornples relative abundance is reduced to slightIy less than 60%: and other species appear. There is a further slight decline in the relative abundance of the Fi-agiinria pinnata complex at 2 cm. corresponding to a greater presence of Achnanthes spp. and Nitschin spp., and the first appearance ofCyn?helln spp. CymbelZn spp. are slightly more abundant in the top section of the core.

6.2.2. Pond 5

Pond 5 (79 O 15'W: 56 O 35'N) is located on the present-day beach, approximately

4.5 m. a.s.1.. adjacent to Eskimo Harbour. It is approximately 2 km NNE of Raised Beach

Pond, and almost 4 km NW of Sanikiluaq.

Loss on ignition (LOI) reported by Moser et al. for Pond 5 shows a uniform decrease from 52 to 9% between the top of the core and 5 cm in depth, followed by an increase between 5 and 6 cm, a slight decline at 7 cm, and a sharper decline at 8 cm to approximately 3%. LOI remains at less than 5, gradually tapering off to 2% at a depth of 199 13 cm, There is an anomaly at 22 cm where LOI increases to IO%, but this drops off at 24 cm to approximately 1%. Biogenic silica values found by Moser closely approximate the profile obtained for LOI, with the exception of the anomalous increase at 22 cm. In the diatom record from Pond 5 there is a much sharper transition in species composition at 5 cm, where the FragiZariu pinnata cornplex declines from approximately 90% to less than

30%. This corresponds to a sudden increase in Denticulatcr kzre~ingiito 45%, and more modest gains by CymbeZZa spp., 1Vifschia spp. and others, which previously had very early occurrences at low levels.

6.2.3. Dry Pond

Dry Pond (79 O l2'W, 56 O 33'N) is located about 3 m from the edge of Sanik

Lake which is south of Sanikiluaq (Sm01 and Douglas, unpublished) (apparently called

Imitavik Lake by Hermanson, 1990, 1991). It has an elevation of 1 1 m. A.S.L. (N.W.T.

Local Governent Town Planning & Lands, Sanikiluaq). Sanik Lake serves as the source of drinking water for the hmlet. At the point at which it was cored, Dry Pond was completely dry and is perhaps best considered an intermittent pool. Dry Pond was not analysed by Moser et al. as the dry condition of the pond made it less than an optimal choice for diatoms, LOI and biogenic silica for this site. 1decided to include it in the combustion particle study as it has an elevation between that of Raised Beach Pond and

Pond 5.

6.3. Methods

6.3.1. Field and laboratory methods

Cores were taken by pushing the coring tube into the sediments by hand, as the 200 ponds were shallow. AI1 sediment cores cvere sarnpled in the field at 1 cm intervais.

Samples were transferred to clean storage bags, labelled and brought back to Queen's

University. The cores were subsampled by M.S.V. Douglas, KA- Moser and myself for diatoms, pollen and combustion studies, respectively. Care was taken to minimize sarnple and subsample exposure in removing the subsamples for this study.

The subsarnples removed were freeze dried by R. McNeely (Geological Survey of

Canada), A second set of sarnples were then removed from this freeze-dried material, cveighed, and piaced in acid-resistant pre-weighed centrifuge for chemical digestion. A modification of the method described by Rose (1993) was used but the hydrofluoric acid step was omitted.

Following completion of the digestion process, known aliquots of a suspension of the sample were placed on clean glass coverslips that measured 22 by 22 mm, using an

Eppendorf pipette cvith disposable tips. Four replicates of each sample were prepared.

The coverslips were tlien dried on a covered slide warmer in a clean cabinet for 12 hours, before mounting with ~~ra...@or ~a~hra..@ mountant.

6.3.2. Dating

Subsamples were also taken frorn Raised Beach Pond and Pond 5 for 'l0pb dating by J.P. Sm01 and M.S.V. Douglas (Appendix 5.1). Based on the results of these analyses, preliminary figures for '"~b and ')'CS in sediments from Raised Beach Pond and Pond 5 have been prepared, sketching out our best estimate relating probable dating horizons with depth and combustion particle distribution (see Figures 6.3 to 6.10). Given that both of these cores were taken in 199 1, this date is taken for the top of the core. The half-life 20 1 of "'~b is approsimately 22.2 years. Thus, a decrease in the activity of "'~b down the

core by 50% cm be equated to a period of time approsimately 22 years earlier, or in this

case to 1969. From these profiles, in Raised Beach Pond, the point of a 50% decrease in

OP^ activity occurs at a depth ofjust less than 5 cm, which would correspond to an

approsimate "'pb date of 1969. J.P. Sm01 & M.S.V. Douglas (pers. cornm.) report that 5

cm has been tentatively dated to approximately 1967, using the Constant Rate of Supply

(CRS) Mode1 of AppIeby & Oldfield (1978).

The occurrence of 13'cs in sediment is associated witli the Cold War atomic fall out, appearing at approsimately 1950, peaking about 1963, then decreasing to Iower levels in more recent sediments. In the Raised Beach Pond core, gamma counts from rhree samples show that there is no detectable '37~sat 8 cm depth in the core, but that at 5 cm 137Cs is definitely present, with levels then declining nearer the top of the core at 2 cm. The actual peak value for Ij7csactivity may faIl above or below the reading made at

5 cm, but. at a minimum, this pattern of values indicates that the sediments in the core are undisturbed. If the 137~svalue at 5 cm does represent the 1963 maximum, and assuming no mobility of Cesium at this site, then our estimate of the E OP^ date of 1969 for a depth slightly less than 5 cm would appear to be reasonable.

Future work using gamma spectroscopy may resolve the issue more fully. It should be noted than Herrnanson (1 990) found evidence of mobility of Cesium downward in some of his cores from the Belchers, and that the Cesium datum may ultimately be less useful than the approximate dates based on 'lOpb. In any event our OP^ and 137~sdata seem to agree. 202 In the sediments from Pond 5, the profile for OP^ activity indicates a decline to

50% of the surface, or 199 1, value for OP^ activity is reached at approximately 4.5 cm

This implies a date of about 1969 at slightly greater than 4 cm depth of sediment. The gamma values obtained for the three sarnple points fiom Pond 5 indicate no occurrence of

137Cs at 23 cm or at 10 cm, whereas the I3'cs activity is definitely rneasurable at 2 cm.

Again, these readings for gamma activity support our interpretation of this core as being undisturbed, and they do not contradict an approximate date of 1969, based on the OP^

IeveIs, at slightly deeper than 4 cm.

6.3.3. Microscopical methods

Samples were selected to intensively document the top 5 cm of sediment, with selected coverage thereafier, either adjacent or alternate samples being chosen. Counts were made of the complete area of the coverslip for each sarnple selected. This work was done using a Reichert Research microscope with transmitted and indirect lighting, and polarizing filters. It \vas fitted with either Nikon or Minolta camera back for documenting particles (Chapters 3 & 4). Particles were classified as to type (Chapter 3) and recorded.

In the case of Pond 5, particles were aIso size classified using a British Standard

Graticule, and recorded.

6.3.4. Statistical analyses

This study is a first exploration of combustion particle occurrence in sediments fiom the mid-Arctic, using the multi-particle type approach discussed in Chapter 3. The data were collected in nominal or categorical forrn, and types are subject to discrimination pnmdy on the basis of qualitative characteristics at this point in the development of this 203 approach. Statistical analyses are consequently very basic. Histograms were prepared for

combustion particles of al1 types, based on the relative abundance of each particle type as

a percentage of the total combustion particle load. Major particle types were identified on

the basis of the histogram of total types.

Histograms of particle occurrence with depth in the core, as a percentage of the

total particle count, were also prepared. Profiles were prepared for seiected particle types.

In the case of Pond 5, size classes were established and particles enurnerated by particle

type were also classified as to size in order to investigate the utility of particle size as a

descriptive factor. As this investigation is an exploratory survey of occurrence and

distribution, no screening of the data to remove minor constituents was performed.

However, major constituent types were identified from the histograms for comparative

purposes, and minor types were included in the "super-groups" of particle types, as

appropriate for comparative purposes in Chapter 7.

6.3. Results

6.4.1. Descriptions of combustion particles from Raised Beach Pond

The particle types observed in the samples from Raised Beach Pond included:

1. spheroidal carbonaceous black

2. spheroidal non-black

3. pleurosphere

4. spheroid

5. charcoal total

6. arnorphous opaque 7. amorpl-ious non-opaque

8. angular opaque

9. aciculate spheroidal

10. coai type

Of the total distribution of combustion particles by type enumerated in the Raised Beach

Pond sarnples (Figure 6.2), charcoal of al1 types, espressed as total charcoai, had a relative abundance of 496, making it the dominant constituent. Spheroidal non-black particles were the second largest component of the total combustion particles observed, at approximately 32%. Generic combustion particles of the arnorplious opaque type had the third highest representation with 10%. Spheroidal carbonaceous black particles contributed 8%. Pleurosphere type, spheroidal type and generic combustion angular opaque type made up the remainder of the particle types observed, with 1 to 3% each.

The profile of the distribution with depth (cm) of the total combustion particle load in the Raised Beach Pond sediment, espressed as the relative abundance of total con~bustionparticles of al1 types by layer as a percentage of the total combustion particles enumerated in al1 layers, is presented as a histogram (Figure 6.3). The general pattern is one of low leveis, from 1 to 4%, in the bottom layers between 15 and 1 1 cm (based on samples at 15, 13 and 1 1 cm), to a ma..imum of slightly more than 30% at the top of the core. Between the top layer of sediment and a depth of 5 cm, the relative abundance of particles decreases to approximately 10% of the total particle load. At 7 cm, the relative abirndance increases somewhat (l2%), then drops to less than 4% in the sarnples reported at lower levels. FIGURE 6.2. Raised Beach Pond, Belcher Islands, Hudson Bay. Histograrn of the total distribution of combustion particles in al1 sarnples from Raised Beach Pond, by particle type.

(a) Spheroidal carbonaceous black particle type (SPCBK)

It must be acknowledged that the SPCBK type constitutes a reIatively small component of the total combustion particle type distribution of Raised Beach Pond

(Figure 6.4), at 8% of the total. However, because of the significance attached to this type, as discussed previously (Chapter 2), It is interesting to look at the distribution with depth of SPCBK type regardless of its low relative abundance.

SPCBK type particles are first observed in the Raised Beach Pond sediment core at a depth of7 cm: corresponding to-an estimated OP^ date of 1930, where they contribute approsimately 1% of the total combustion particle load. This corresponds to an approsimate OP^ date of 1920. SPCBK were not detected in the sample at 5 cm, but . appsar at 3 cm, again contributing about 1% of the total of al1 particles enumerated. From the depth of 3 cm (corresponding to about 1984), to the surface of the core, the relative abundance of the SPCBK type doubles with each 1 cm increment to the top of the core,

\\thers this type contributes a maximum of 4% of the total combustion particle load.

(b) Charcoal: total for al1 charcoal types (chtot)

The profile showing the distribution of the relative abundance of the charcoal component of the total combustion particle load in the Raised Beach Pond sediment is presented in Figure 6.5. Given the dominance of charcoal in the combustion particle inventory of types from this site as a wbole (Figure 6.3), it is not surprising that profile for charcoal total alone with depth (Figure 6.5) closely resembles that for the total of a11 combustion particle types (Figure 6.3), including the stronger point at 7 cm. There is, however, one small but possibly significant difference between the two: at the top of FIGURE 6.3. Raised Beach Pond, Belcher Islands, Hudson Bay. Histogram of the profile of the total distribution of combustion particles of all types with depth (cm) and OP^ dates. Raised Beach Pond relative Abundance of combustion particles with depth O 5 10 15 20 25 30 35

Depth (cm)

Years (estimated 21 0- Pb)

Activity (Bqlg ) FIGURE 6.4 Raised Beach Pond, BeIcher Islands, Hudson Bay. Histogram of the relative abundance (%) of spheroidaI carbonaceous bIack particle (SPCBK) type with depth (cm) and 'IOpb dates. Raised Beach Pond SPCBK relative abundance with depth and date O 1 2 3 4 5

Depth (cm)

9 209 the core, the relative abundance of the total combustion particle load increases, as

described above but the relative abundance of the charcoal total contribution declines in

this sarnple to approsimately 3%. from a maximum of slightly more than 10% at a depth

of 2 cm. This reflects? in part, an increase in particles from sources other than biomass

burning.

In order to provide more detail as to the possible the relationship among particle

types. particularly with regard to the top 1 cm of the sediment, 1 prepared a different type

of conlposite profile. For each of the Raised Beach Pond sarnples, 1 prepared a separate histogram representing the total conibustion particle distribution in that sarnple by type

These independent histograms were then stacked according to sediment depth.

By treating the distribution of combustion particles in each sediment sample anatysed in the core as a distinct population, and espressing the histogram of the frequency distribution of particles by type in the form of a bar graph \vit11 particle type proportions on a single bar, it is possible to prepare a combustion particle spectrum for each sample. Assembling these spectra in order of deptli and linking them vertically according to type, generates a composite profile of relative abundance at each depth for each combustion particle type. 1am using the term "combustion particle spectra" to describe this format as an analogy with pollen spectra (Faegri & Iversen, 1989). On the basis of relative abundance within samples, the difference between the total of a11 combustion particles and the contribution of the charcoal total in the top layer can be attributed to, in order of magnitude of contribution: spheroidal non-black (SPNBK), FIGURE 6.5. Raised Beach Pond, Belcher Islands, Hudson Bay, Nunavut. Histograrn showing total distribution of charcoal particles of a11 types for ail sarnples analyzed. Raised Beach Pond Occurrence as percentage relative abundance of charcoal with depth (cm) and etimated dates (210-Pb) O 2 4 6 8 10 12

Years (210-Pb Depth '91 ' estimated) 21 1 spheroidal carbonaceous black (SPCBK), and generic combustion opaque (cmop).

6.4.2, Descriptions of combustion particles from Pond 5

Combustion particles in Pond 5 samples were counted and classified in three ways: first by general category, second, by detailed subcategories and third by size. In the sampIes from the Pond 5 core, the following combustion particle types were recorded:

1. spheroidaI carbonaceous black (SPCBK)

2. cenosphere

3. spheroidal non-black type (SPNBK)

4. pleurosphere

5. charcoal blocky

6. charcoal angular

7. charcoal lath

S. charcoal lacy

9. charcoal amorphous

10. combustion Iacy

1 1. amorphous mised opaquehon-opaque

12. combustion angular

13. combustion rounded

14. combustion arnorphous

15. combustion arnorphous rounded

16. coal type: blocky

angular rounded

17. resinous, cellular: irregular

spheroidal

Numbers 1 to 15 were recognized as combustion-associated and included in the classified types for purposes of analysis. Number 16, coal type, was excluded from further consideration at this time. Number 17, resinous cellular spheroidal or irregular shaped particles. is excluded from the combustion particle total, and from further consideration here (see Chapter 3 for further information concerning tlie classification).

A histogram showing the relative abundance of combustion particles by type as a percentage of the total combustion particles enumerated in the Pond 5 sarnples was prepared (Figure 6.6). Of tlie combustion particle types obsenred the most abundant was total charcoal (8S%). consisting of tlie following cateçories: charcoal blocky, charcoal angular, charcoal lath. charcoal lacy. charcoal amorphous and charcoal rounded. Generic combustion (numbers 10 to 15 in tlie list above) of al1 types made up approximately 9% of the total. Spheroidal carbonaceous black, spheroidal non-black, pleurospheres and cenospheres contributed the remaining 3%.

Figure 6.7 shows a histogram of the distribution of the total combustion particle load of al1 types with depth at Pond 5, as well as inferred OP^ dates, so that the proportion of the particle load corresponding to a particular depth is clearly shown.

Perhaps the most striking feature is the position of the maximum, accounting for approsimately 19% of the total combustion particle distribution, at 4 cm from the surface.

From the change in level of activity of 'I0pb, a date of 1968 is estimated for tliis layer. 213 This is very close to the depth at which Moser found that loss on ignition values began

their drarnatic increase toward a their present-day maximum. The Ievel of total

combustion particles in the Pond 5 sarnples at 3 cm then decreases to approximately 1l%,

rïsing slowly over the next 3 cm to the top of the core, where a second maximum occurs.

Approximately 17% of the total combustion particle load is found in the sarnple representing O to 1 cm, Below 4 cm, the relative abundance of total combustion particles

in each sample also decreases in samples from 5 and 6 cm. However, at 7 cm, there is a slight increase to approximately 12% of the total, declining to 7% at 8 cm.

(a) Spheroidal carbonaceous black particle type (SPCBK)

The contribution of the spheroidal carbonaceous black type to the total combustion particle inventory of Pond 5 is quite small in terrns of relative abundance, as shown by Figure 6.6. Wowever it is useful to set out a profile of SPCBK type particles at an espanded scale in order to explore the relative abundance of these particles with depth as a percentage of the total combustion particle occurrence. This profile of SPCBK type particles is presented in Figure 6.8. The two profiles have similar patterns of maxima and minima (although the scaies are quite different), with the exception of the sample from the top of the core, where the reIative abundance of SPCBK type particles is three times greater than in the adjacent sample. For the total combustion particle distribution, however, the total combustion particle relative abundance in the sample at the top of the core is only approximately 25% greater than that of the adjacent sample. fb) Charcoal: total distribution for aII charcoal types (chtot)

Given the dominance of charcoal in the profile of total combustion particles for FIGURE 6.6. Pond 5, Belcher Islands, Hudson Bay, Nunavut. Histograni showing the relative abundance of combustion particles by type, as a percentage of the total combustion particles enurnerated in the Pond 5 sarnples.

FIGURE 6.7. Pond 5, Belcher Islands, Hudson Bay, Nunavut. Histograrn of the dative abundance of the total combustion particle Ioad of al1 types as a distribution with depth (cm) at Pond 5, showing inferred OP^ dates. Pond 5 Histogram of total combustion particle distribution with depth

1 1991

3 1980

5 1944

7 1865

11 1828' Year Depth (cm) (estimated 13 21O-P b)

19 - - - - 21 -

23 tI It Ii f1 I

Activity (Bqlg) 216 Pond 5, it is not surprising that the profile for the relative abundance of total charcoal with depth (see Figure 6.9) is very similar to that of total combustion presented in Figure

6.7. There is a secondary maximum at the surface, but the primary maximum occurs at 4 cm, dating to approximately 1968. There have been fluctuations in relative abundance of charcoal present in the sediment, but the range throughout the profile has been fiom 7 to

17% approximately, at each of the sample depths analysed.

I have also explored the question of similarity and difference with respect to the temporal distribution of particle type categories in Pond 5.1 recognize that, as in the case of SPCBK type particles, these particles are present in such low proportions that they can only be used as an illustration of a pattern. In this case, there is a maximum in the sample at the top of the core, wliich decreases relatively regularly to 4 cm then more abruptly to 6 cm. At 7 cm there is a slight increase, followed by a decline at 8 cm.

(d) Combustion particle size distributions

The Pond 5 sarnples were investigated for combustion particle size class distribution in addition to particle type. Figure 6.10 (a), (b) and (c) present the results of the size class distribution for al1 combustion particles enumerated in the Pond 5 sarnples, for total charcoal type particles, and for spheroidal carbonaceous particles (SPCBK type), respectively. The histogram showing the distribution by size cIass of al1 combustion particles enurnerated resembles a normal distribution with a slight skew toward the smaller particle size classes (Figure 6.10 (a)). The distribution of the total charcoal

(Figure 6.10 (b) strongly parallels that of (a), which is to be expected given that charcoal FIGURE 6.8. Pond 5, Belcher Islands, Hudson Bay, Nunavut. Histogram of the distribution of spheroidal carbonaceous black type combustion particles to the total combustion particle load with depth (cm), at Pond 5. Pond 5 SPCBK relative abundance with depth

Depth (cm)

16 Ye r (estimate 17 210-P b) 18 19 20 21 22 23 1 1 1 1

Activity (Bqlg) FIGURE 6.9. Pond 5, Belcher IsIands, Hudson Bay, Nunavut. Histograrn of the relative abundance of total charcoal with depth. Pond 5 distribution of total charcoal

9 IO 11 Years Depth (cm) 12 (estimated 21O-P b) 13 14 15 16 17 18 19 20 21 22 23

0.2 0.3 Activity (Bqlg) FIGURE 6.1 0. Pond 5, Belcher Islands, Hudson Bay, Nunavut. (a), (b) and (c) present the results of the size class distribution for the total of ail combustion particles enumerated in the Pond 5 samples; for the total charcoal type particles; and for the total spheroidal carbonaceous particles (SPCBK type), respectively. Particle size classes - midpoints and extremes

Particle size classes - midpoints ànd extremes

Particle size classes showing midpoints and extremes 220 types contribute 88% of the total combustion particle load. Perhaps the most interesting aspect of this distribution is the extent to which the larger size classes are represented: approximately 43% of the charcoal particles enumerated faIl into the size classes with a median value of 4.5 and up (values are graticule scale values of relative size).

The distribution of SPCBK type particles in Figure 6.1 O (c) appears rather different from the preceding esamples, in that the distribution is quite skewed and particles in the smaller size classes dominate. At just 3% of the combustion particle total, this is not compelling evidence, but it is suggestive of the possibility of a different history for particles in this category, which might usefully be investigated.

6.4.3. Descriptions of combustion particles from Dry Pond

A third site was similarly investigated, and combustion particle occurrence was catalogued and recorded. Due to space limitations, this materiai appears in Appendix 6.2.

6.5. Discussion

The results of this preliminary investigation of combustion particles in the sediments examined from Raised Beach Pond, Pond 5 and Dry Pond indicate that the profiles of combustion records reported here reflect the general trend toward increasing levels since 1850. This pattern has been observed in other regions and was discussed in

Chapter 4. In addition to this generally observed trend toward increased deposition of combustion products in recent sediments, there is a change in the relative composition of the spectrum of combustion particles in the samples fiom the Belchers with sediment depth, corresponding to change over time.

Combustion particle sources may be local or regional. In order to begin to sort out 22 1 the patterns of occurrence of combustion particle types in the sediment, it is helpful to have an appreciation of the rates of deposition, as cvell as an understanding of local and regional sources, both contemporary, and historical.

Frorn the estimated 'lOpb dates for Raised Beach Pond and for Pond 5, it is possible to reconstruct approximate sedimentation rates. For Raised Beach Pond, the average sedimentation rate for the '"~b-dated core segment is approximately 1 mm yr -'.

For the '"~b-dated core segment of Pond 5, the average sedimentation rate is approximately 0.6 mm yr -'. For an estimate of incremental sedimentation rates for both sites based on OP^ dates, see Table 6.1 & 6.2.

In order to produce combustion particles, there are three basic conditions that niust be met: fuel must be available (defined as combustible organic matter, for purposes of this study), a spark or other source of ignition must be in contact with the fùel, and in general, oxygen must be available to support combustion. Combustion in ecosystems is either triggered by the interaction of biophysical conditions, including the moisture regime and the frequency of lightning strikes (Weeks, 1976), or by human intervention, either deliberate or inadvertent. The presence of combustion particles is evidence of past buming of a fuel, either near the site where the bumed residue is found, or remote from the site, in which case a connection to the depositional Iocation by wind or by water, is expected.

In the case of the Belcher Islands combustion record, the choice as to probabIe combustion locus is restricted to either local anthropogenic activity or to long-range transport effects by the nature of the site and its location. 1 am particularly interested in 222 what is known of human-initiated fire activity in the case of the Belchers, as it may assist

in developing a rneans of discrirninating between local and regional fire activity in the

interpretation of the sedimentary fire record in the Arctic more generally. Unlike the sites

discussed previously (Chapters 4 & 5), the Belchers have a recent history of Inuit land use

extending to the time of first contact with Europeans. The Belcher Islands have been

inhabited by Ungava Inuit and also used sporadically by hunters frorn what is now

Northern Quebec since the pre-Contact period. Henry Hudson is reported to have sighted the islands, but the first real contact between western society and the peopIe living in the

Belchers took place in 19 14 (NWT Data Book, 1990/91).

The present community of Sanikiluaq was established in 1967 (Herrnanson, 199 1) and becarne a hamlet in 1976 (NWT Data Book, 199OB 1). In terms of development,

Sanikiluaq is not an industrialized centre, but rather is dependent on the renewable resource economy. However. like many other arctic communities, Sanikiluaq has local conlbustion sources, including a diesel generator that provides local power and an open garbage durnp. Open burning of garbage is a common practice. A relatively low power diesel generator (20 kW) was first used in the Belchers between ca 196 1 and 1969, at

South Camp. Afier the camp was relocated to North Camp (now Sanikiluaq), a more powerful General Motors@ generator (80 kW, with a backup unit of 70 kW) was used.

Most recently, the Sanikiluaq power station was built in 1985 to house three larger generators (each a Caterpillara 325 kW unit) (Chris Irving, pers. commun.).

Before the adoption of diesel, coal was irnported frorn Wales and

Newcastle by traders and missionaries for heating (David Murray, pers. commun.). TABLE 6.1 Raised Beach Pond Sedimentation and Combustion

Core ~ear" Sed. ~ate" Chronology of combustion-related events or depth development" 19 (cm yr -') (cm)

1.5 Manitoba fires 1985 Sanikiluaq power station 3x325 kW turbines (CaterpillarO) 0.25 0.14 1969-70 South Camp moved to North Camp ls80 kW turbine (General MotorsB )(store) O. 1 ca 196 1 - ca 1969 South Camp operational -20 kW generator 0.06 N. Ontario fires: * 1914 Hearst - 1 12 km strip * 19 16 Matheson - 64 km front (-202,000 ha) * 1932 Haileybury (-1 2 2,000 ha) 0.05 N. Ontario fires: * 191 1 Porcupine ( -200,000 ha)

0.09 *N. Ontario fires: 1882 Mattagarni Lake *N.Ontario fires: 18 13 & 1794 Moose Factory to Kenogamissi (Matagami River) *N. Quebec fires: 1661 Tadoussac to James Bay

- --- - '' Note: The forest fire information marked with an astensk (*) is unpublished work by Dr. K Abel, Department of History, Carleton Universisr. l9 Sediment depth (cm) 'O Estimated fiom OP^ " Estimated rate of sedimentation (cm yr -') " Note: Where the year of occurrence does not match any sediment horizon's estirnated 210 Pb date, the actual year is given and the entry appears on a separate line. 324 TABLE 6.2 Pond 5 Sedimentation and Combustion chronologyU

Core ~ear" Sedimentation Chronology of combustion-related events" 21 26 (cm yr -')

1985 Sanikiluaq power station 3x325 kW turbines (CaterpiIlar@)

1969-70 South Camp moved to North Camp - 1x80 kW turbine (General Motors@ ) (store)

Ca 1961-ca 1969 South Camp - generator (-20 kW)

N. Ontario fires: * 1922 Haileybury - (-1 2 1,000 ha) * 19 16 Matheson - 64 km front (-202,000 ha) * 1914 Hearst to Haileybury - 1 12 km strip * 19 1 1 Porcupine (-200,000 ha)

N. Ontario fires: * 1882 Mattagarni Lake

*N. Ontario fires: 181 3 & 1794 Moose Factory to Kenogamissi (Matagami River) *N.Quebec fires 1661 Tadoussac to James Bay

'3 Note: The forest fire information marked with an asterisk (*) is unpublished work by Dr. K Abel. Department of History, Carleton University. '' Sediment depth (cm) Estimated from OP^ '6 Estimated rate of sedimentation "Note: where year of occurrence of the fire or related development does not match any sediment horizon's estirnated OP^ date, the actual year is given and the entry appears on a separate Iine. 225 Clearly, it is reasonable to espect that local combustion sources are likely to have had an influence on the combustion record, and that indications of coal and diesel combustion in the sediment, as well as of the incineration of garbage, may be found. in addition it appears likely that the contribution of mobile combustion sources to sediment are increasing, particularly in relation to community maintenance and construction projects (Chris Irving, in litt.).

Combustion particles appearing in the sediment record after an approximate date of 19 14 may be suspected of originating locally, but with a Iow probability, at Ieast until approximately 1960, when Iocal power generation using diesel as fbel becarne a regular occurrence. From 1960 on' the probability of a local origin for fossil fuel combustion particles increases as a resu1t of increased population and increased combustion of al1 types.

This chronology of contact and settlement suggests that combustion particIe types which can be Iinked to burning of fossil fuels found in sediments with an estimated date earlier than 19 14 are likely to be regional rather than local in origin. In terms of sediment depth, for Raised Beach Pond, fossil fuel related combustion particles occurring just above, at, or beIow 7 cm are almost certainly due to transport. In the case of Pond 5, particles at 6 cm are almost certainIy pre-1914, and some of the particle content of the 5 cm horizon may aIso be. These records of occurrence are discussed under long-range transport below.

Afier 19 14 up to the early 196Os, the focal point of anthropogenic fossil fuel related combustion is likely to have been South Camp, where the store and school were 226 located. From the penod of the consolidation of settlements on the Belchers marked by the move of South Camp to North Camp in 1969-1 970, North Camp (now Sanikiluaq) would be the centre for Iocal fossil fùel combustion sources. The net effect would be to rnove the sources closer to the study sites and an intensification of the source to sediment signal reflected in particle relative abundance, would be expected after 1969-70.

This by no means rules out the possibility of seeing the long-range transport of combustion particles from regional sources. In Raised Beach Pond and Pond 5, the charcoal particle record appears before 1914, as estimated from the OP^ profile. It would seem reasonable to characterize this early portion of the charcoa1 particle record as resulting from long-range transport from fires on the mainland, as fuel is scarce on the

Belchers. Although these levels are not high early in the sediment record (510% in Pond

5 and -2% in Raised beach Pond), they are detectabIe. Nearer to the 19 14 date of

"contact", charcoal levels increase markedly in Raised Beach Pond and less so in Pond 5

(Figures 6.5 & 6.9). This appears less likely to be due to the arriva1 of expeditions in the

Belchers than to a number of intense and large fires in Northern Ontario and Quebec that would have increased the availability of combustion particles for transport, provided a convection mechanism for lofting them, and reduced the capacity of the immediate landscape area to trap them (Tables 6.1 & 6.2). At present, regular observation of smoke- laden air at the Belchers, particularly from the south are reported and in 1988 smoke from forest fires in Northern Manitoba reduced visibility in the Belchers to 30 rn on one occasion (Chris Irving, pers. comm.).

Biomass combustion is considered to be a usual feature of the Subarctic and 227 Arctic regions: botli the boreal forest and tundra regions have a long history of fire

occurrence, as documented by Filion et al. (1 99 1) in the case of Northem Quebec, and in

Keewatin (Nichols, 1970). Conditions apparent in recent time penods are expected to

have existed in the past as well. However, in al1 of the major conflagrations in Northern

Ontario between 19 11 and 1922, included in Table 6.1 and 6.2, human activity related

variously to logging, mining, settlement and raiiroad access was identified as a factor in

starting the fires. This suggests that the peak in charcoal in the Belchers dating from

about this time should probabIy be interpreted as long-range, but due to a combination of

environmental and human factors.

The airbome transport of industrial combustion particles to the Belchers would

seem to be possible as weII, given that the presence of arboreal tree pollen is reported

from the Belcher Islands sediment cores by Moser et al. (unpublished). Studies of forest-

related material such as charcoal and pollen from other regions have provided evidence of

long-range transport of pollen and charcoal (Terasmae, 1967, Fredskild, 1984, Nichols,

1978, Bourgeois et ai. 2 985). While it is tnie that the Belchers are located at a latitude corresponding to treeline on the mainland, and therefore perhaps closer to pollen and charcoal sources than to industrial combustion sources, strong winds are present and many combustion particles have been shown to be readiiy transported long distances by wind (Delany et al., 1967; Rosen, L968; Welch et ai., 199 1).

Although the Belchers are clearly arctic in climate, vegetation and geospatial relationships, they are not necessarily remote from more developed regions with respect to ecophysical and meteorological conditions. Hermanson (1990) makes reference to 228 work by Robbins (1978) and others, showing that severe storms in the Great Lakes region have been known to follow storm tracks which pass over the Belchers. Two powerfûl storms, one in Lake Michigan on November 11, 1940, and another in Lake Erie on

November 18, 1958, were observed to cause disturbances of the sediment in those lakes.

Hermanson (199 1) has interpreted disturbances that he observed in Imitavik (Sanik) sediment cores as effects of these storms as well. Apparently the storrn track of the

November 18, 1958 storm was charted passing over die BeIchers on November 19.

Hermanson also attributes discontinuities in the radioisotope profile to these storm- related disturbances of the sediment, suggesting that they can be used as marker horizons.

Two important points arise from these reports: one, that the connection between the Great Lakes airshed and the Belchers is strong and recurrent, and two, that delivery of airborne materials from the Great Lakes region to the Belcliers has occurred and is to be espected. at least on an episodic basis.

In terms of industrial point sources, although there is no industry located on the

Belchers, significant point sources for industrial particle emissions esist in Northern

Ontario and Northern Manitoba that may contribute to ambient particle loads on a regional basis. Work by Henderson (1996) describes transport of industnal emissions from Flin Flon, Manitoba in the direction of James Bay with the prevailing wind. There are also reports of the detection of emissions from the smelter complex at Sudbury being detected at ScheffervilIe, Quebec. A transect joining these locations would pass just south of James Bay and the Belchers (D. Murray, pers. commun.). In addition to these smelter facilities, Northern Ontario also has coal fired electrical generation plants at Atitkokan 229 and Thunder Bay- Again, there is reason to suspect that combustion particles, in this case from industrial activities, rnay reach the Belchers by regional and long-range transport.

In the Raised Beach Pond (RBP) sediment profile, below 10 cm which corresponds to the estimated OP^ date of pre-1888, 10% of al1 combustion particles present are observed (Figure 6.3), Most of which are charcoal (Figure 6.5). These particles can most reasonably be attributed to long-range transport.

In the RBP sanlple from 7 cm, dated to between 191 1 and 1949 approximately, there is relatively strong combustion signai (Figure 6.3). This spike is largely composed of charcoal (Figure 6.5), but also marks the first appearance of spheroidal carbonaceous black type particles (SPCBK), at a very low level of relative abundance (Figure 6.4).

SPCBK type particles are not observed at 5 or 4 cm, but do reappear at 3 cm.

6.6. Conclusion

The work presented here Iends encouragement to the further development of this approach to combustion particle documentation. In the Belcher Islands, particles are generally more abundant numerÏcally, by an order of magnitude with respect to the raw counts in comparison with Horseshoe Pond, for exarnple. Although it is more challenging to deal with a greater variety of types, at the same time there is greater expectation that relationships cmbe drawn out. This chapter, like Chapters 4 and 5, provides an exarnple or test case for the development of this approach, as well as stimulating thoughts about future research (Chapter 7). CHAPTER 7

OVERVIEW, DISCUSSION, CONCLUSIONS

AND RECOMMENDATIONS FOR FUTURE WORK

In each of the preceding chapters, the emphasis has been on problems of

combustion partide identification and the recognition and description of patterns of

combustion particle occurrence. In Chapters I and 2,I sketched out the broad dimensions

of the many relevant fields of inquiry which contribute to Our current understanding of the

nature of combustion particles, the processes by which they are created, the mechanisms

which play a role in their distribution, and the nature of the effects these particles may

have on the environment. In Chapter 3,1 exarnined the attributes of a range of combustion

particies from known reference materials and from the sites chosen for this study, using

light microscopy. Two findings emerged from this work on the description of the

combustion particles: first, the array of possible conformations of combustion particles is

vast, and second, some ordering of this array into categories is necessary if we want to

examine patterns of occurrence.

As a result of this work 1 developed two types of tools: one to sort combustion

particles observed in sediment sarnples, and one to describe them. The first, an illustrated diagnostic key, which emphasized combustion features that may prove to be important in understanding particle occurrence or effects, was presented in Chapter 3. The second tool that 1 prepared is a synoptic key (in the sense described by Pankhurst, 1979), that sets out, in the form of an artificial classification (Appendix 3.l), a description of the &y of 23 1 combustion particles that 1 have observed in this study. This synoptic key is not presented for purposes of identification in a taxonomie sense, but rather as a step towards greater discrimination among combustion particles in environmental samples, the significance of which is not well known. For exarnpIe, 1 have seen particles which, by virtue of their characteristics, 1 cm recognize as distinctive groups, but for which I need additional information to match to a source. 1 have also seen particles that very closely resemble those from known sources, and for which it is possible to suggest a correspondence and ultimately an explanatory mechanism for their occurrence (for example. see Chapter 3,

PIate 1 1).

Finding an approacli that is tolerant of arnbiguity, at least at the outset, was important to me for practical purposes. Particle identification skills (in the strictest sense) are acquired through esperience over a long period of time. There are always uncertainties due to the relationships among fuels and the parallels between processes of particle formation. Enough information esists with respect to combustion particle samples from known sources to validate the utility of artificial ~Iassification(Fisher et al.,

1978) and to justie the risk taken in attempting to develop a meaningful adficial classification of combustion particles in the environment for purposes of paleoIimnological interpretation.

In Chapters 4, 5 and 6,1 presented the combustion particle records, documented using the classification developed in Chapter 3, for specific sites from Alert ai the north end of Ellesmere Island, to Cape Herschel mid-way down the eastern coast of

Ellesmere, to Hawk Lake in Keewatin on the West coast of Hudson Bay, and finally to 232 three sites in the Belcher Islands. These exarnples provide a basis for exploration of this approach to combustion particle classes based on combustion particle features, in addition to absolute identification in some cases, in the context of environmental factors that rnay influence their distribution. The larger question of interest to me when 1 began this project, beyond that of the problem of combustion particle ciassification, and the documentation of combustion particle records in sediments from lakes and ponds at specific sites in the Arctic: was whether or not the distribution of combustion particles here can be related to the larger patterns of transport and deposition that influence the presence of contaminants in the arctic ecosystem. 1 now briefly examine the potential of the approach presented here for addressing these larger-scale regional questions.

The current scientific consensus as to what is now known of the important source areas and pathways of contaminant transport to the Arctic is summarized, in part, in

Figures 7.1 and 7.2. Although ocean currents are unlikely to have contributed directly to the deposition of combustion particles in the sediments of the lakes and ponds studied here over the pst 200 years's, and air rnass movements are the pathway of primary interest, there is a relationship between ocean currents and air masses that may be relevant to questions of combustion particle transport. Cornparison of Figures 7.1, 7.2 and

7.2 serves to draw attention to the importance of the Northern Hernisphere's industrial regions in relation to pathways of pollutant transfer, and to the study region.

'' ~lthough,for exarnple, many of the coastal lakes in Northem Ellesmere Island did have marine connections following postglacial emergence (Retelle, 1979); and Herring (1 977) (cited in Griffin & Goldberg (1979)) did find combustion particles in ocean sediments, it is highly unlikely that ocean currents could be directly responsible for particles found in the sampIes studied here. FIGURE 7.1 Schematic map of central industrial areas and dominating air currents as identified by the Arctic Monitoring And Assessrnent Program (AMAP?1994). Central industrial areas

Dominant air currents FIGURE 7.2 Known pathways of pollutant transport in the northern hemisphere. as identified by the Arctic Monitoring And Assessrnent Program (AMAP, 1994).

FIGURE 7.3 Major ocean current influences linking the North Atlantic and the Eastern Arctic. The long arrow indicates the Gulf Stream.

To sumrnarize what 1 found at the selected study sites using the particle categonzation 1developed in Chapter 3,I have combined the data fiom Chapters 4, 5, and

6, and assembled it into a regional picture of the north-south transect fiom Alert to the

Belcher Islands-

To facilitate cornparisons between very different sites, I have identified five

"super groups" or super-categories of combustion particles. These super groups of particles. based on the classification developed in Chapter 3, are:

spheroidal opaque, which includes simple and complex opaque spheres, and

cenospheres,

spheroidal non-opaque. which included simple and complex non-opaque spheres, and

pleurospheres,

charcoal of al1 types,

generic combustion, opaque, which included al1 shapes. structures and consistencies

of opaque particles, and

generic combustion, non-opaque, and mixed which included al1 shapes, structures and

consistencies of non-opaque particles.

While this is a very preliminary treatrnent of data resulting from the particle survey, classification and enurneration from the selected sites, and these broad groups do not permit a fine scale of discrimination, they are sufficiently distinctive to permit the regional distributions of combustion particles to be exarnined. They also serve as a basis for a crude test' at the level of regional influence, of the utility of the approach presented here. 23 7 Two kinds of composite samples were created from the count data from Chapters

4. 5, and 6. The first one treated the total particle content of the samples counted for each site, adjusted by the number of sarnples analysed for each site, to give a "standardized" value for particle occurrence at that site. This was done to compensate for the variation in numbers of samples analysed from each core. The value obtained was then used to calculate a standardized percentage relative abundance that is designated as "(std) %" in the appropriate figures. The adjusted sarnple values were then used to prepare the charts and geographical distributions. The results of the treatment of the total samples from al1 sites as a composite sarnple are presented in Figure 7.4 where the distribution of super group A is shown on the map, and those for the remaining super groups are shown below it.

The second composite sarnple was created by taking the particle counts from the top sarnple layer of each site, for each of the "super groups" listed above, as a fraction of the total particle rain represented by that layer for al1 sites enurnerated. This value was expressed as a percentage relative abundance for each of the particle super groups in relation to the North-South transect. The results are shown in Figure 7.5 where the relative abundance of super group A in the top layer is plotted on the map to illustrate the spatial distribution and the results for the remaining "super-groups" are presented beneath the map.

The most obvious outcome of this preliminary analysis is that distinct differences exist arnong the sites sarnpIed, both in the samples for the top of the cores which reflect recent impacts, and in the comparison of standardized values for al1 samples analysed. FIGURE 7.4 Relative abundance of the total particle record of super groups A, B, C' D and E at al1 of the sites, expressed as a percentage of al1 of the sample sets analysed. Values were standardized to take into account variations in the numbers of samples. ,-----1\ /' \ '. ... Supergroups

>and 5 1l Raised Dry Hawk Horse- Self Kirk Beach Pond Lake shoe Pond Lake 1 Pond Pond FIGURE 7.5 Relative abundance of the combustion particle record of super groups A, B, C, D and E in the top layer at al1 of the sites, expressed as a percentage of the total number of particles observed in these sarnples. - __----.--._ ------* - -. -. -. Supergroups

I l l 1 i1 I I I 1 i i i I 1 l 1 I l i j i 1 I 6.7..!%1 q,% L -8% i 9% 1 1% 04.0- l t 1 i i I Il I 1 : II -32% iA6!%I9L0iii 3-YLL

-00% 0% 0% 0%

?ond 5 Raised Dry Hawk Horse- Self Kirk Beach Pond Lake shoe Pond Lake Pond Pond 240 The super group C, which represents charcoal as a standardized value for al1 samples

from each core (Figure 7.4), and the total charcoal content in the top layer (Figure 7.5),

displays a general trend with the majority of charcoal particles found in the more

southerly sites, and gradually tapering offto values of zero, or approaching zero, at Alert,

the most northerly site. This corresponds roughly to a decay in signal strength with

distance from treeline (see Figures 7.6 and 1.1). The top layers of the sediment show

slightly higher proportions of charcoal in the more northerly sites than do the

standardized values for each core as a whole. This seems reasonable, as increasing

biomass combustion emissions on a global basis (Clark et al., 1994) can also be expected to result in rising levels of combustion particles in sediments in the Arctic. It is also reasonable. in light of increasing effects of human activity locally, with expanded con~bustionparticle generation capabilities. particularly in recent years'9.

The combustion particle profiles observed for super group A (splieroidal opaque particles) clearly follow a different pattern from that described for charcoal particles of a11 types (super group C) above. When the standardized relative abundance, based on the total particle record at each site, are compared, the transect is dominated by the Alert record (51% of total particle occurrence for this super group is found here), and the three sites from the Belcher Islands have quite similar levels of occurrence (1 1, 12, and 12% for Pond 5, Raised Beach and Dry Pond, respectively, see Figure 7.4). However, when a comparison is made of particles in this category in the tops of the cores (see Figure 73,

"> It has been suggested that the power generating capacity of a11 of the Distant Early Warning Site installations was equivalent to that of a mid-sized city (M. Kostiuck, Issues Analysis Paper, Geography 45.570C, Carleton University, March 1999. FIGURE 7.6 Map showing the location of treeline and the 10" C July isothem.

242 the proportion of total particles found at Alert is now 23%, with an increase in the contribution from the three Belcher Island sites to 65% of the total- 1interpret this as indicating at least ttvo different source areas, one dfecting AIert more strongly, and one or more others influencing particle occurrence indicating at least two different source areas, one affecting Alert more strongly, and one or more others influencing particle occurrence in the Belchers, the relative strengths of which in the Belchers, the relative strengths of which are changing. This appears to be primariIy due to increases in super group A-type particles at the Belcher Island sites probably due to developments to the C south (see Chapter 6),and possibly to reduced local combustion particle emissions at

AIert (see Chapter 4 for discussion). I interpret this as also indicating tliat site factors have assumed greater significance in explaining the distribution of combustion particles in the environment, possibly as a result of new local sources (see Chapter 6 for example) or seographical relationships with new regional sources (see Figure 7.7, for examples).

Further studies of site factors related to particle deposition are needed to dari@ this.

A comparison of particle size class distributions for the spheroidal black particle type, excluding cenospheres and cornplex particles, from three of the sites (Horseshoe

Pond, Cape Herschel; Hawk Lake, Keewatin; and Pond 5, BeIcher Islands) is shown in

Figure 7.8 a, b, and c. There is a very slight increase in the occurrence of slightly larger size classes, in the more southerly sites (Hawk and Pond 5). However, the relative abundance of these particles, expressed as a percentage of al1 particles enumerated, appears higher in Horseshoe Pond, the more northerly site. The word "appears" is used advisedly, given the generally lower Ievels of particles at Horseshoe Pond, a smaller 243 absolute number constitutes a greater proportion of the total. This effect may also be

exacerbated by increased dilution of the combustion particle record by temgenious

sedirnent (M. Retelle, pers. comm.). Figure 7.9 shows selected particle size distributions

by particle type (not super group) as represented by size classes based on particle

diameter, for Horseshoe Pond. It should be noted that, in ail of the size classes recorded,

the percentage of spheroidal black particles (SPCBK) occurring in each size class is less

than 10, and that for each sample the number of SPCBK present does not exceed Z 1.

One of the most surprising outcomes, in my view is that the variation between

sites, particdarly sites that are geographically close, is so great. For example, the contrast

between combustion particle records for Kirk Lake and Self Pond was very interesting

(see Chapter 4- Figures 4.2 and 4.4, for example). While sorne findings, such as the large

(>50 pm in length) lath shaped charcoal particles at Kirk Lake, can be attributed directly

to hiunan activities at the site (including barbecuing on the ice-covered lake surface), other variations are not as so easy to explain in their origin. In the case of Self Pond, the most likely explanation is that site-specific factors, such as emissions ti-om locd combustion sources and prevailing winds, have swamped any other regional signal. In the case of the Belcher Islands, the other factors that may play an important role are elevation and aspect, or degree, of exposure. For exarnple work by Bourgeois (1990) on pollen in ice from glaciers in the Eastern Arctic, and Alt (1987) on air masses over the Queen

Elizabeth Islands. suggest that air mass movement, composition and resultant deposition may have a component related to altitude. Raised Beach Pond (Chapter 6) is at an FIGURE 7.7 Map showing the location of known sources of emission of airborne particulates in relation to the transect from Alert to the BeIcher IsIands. Dominant air currents are shown and the Gulf Stream is indicated. Source of Combustion and Related Particles @

Air currents >

Gulf Stream --s------FIGURE 7.8 ParticIe size distributions of spheroidal black particles by particle diameter size class show as percentage relative abundance with depth in core for a) Horseshoe Pond, Cape Herschel; b) Kawk Lake, Keewatin; and c) Pond 5, Belcher Islands- >7 6.5 5.5 4.5 3.5 2.5 1.5 cl Size Classes

Particle size class - midpoint and extremes

Particle size classes showing midpoints and extremes FIGURE 7.9. Horseshoe Pond, Cape Herschel, Ellesmere Island. Relative abundance of particles by particle type?particle size (maximum diameter), and depth. LEGEND HORSESHOE POND PERCENT SPCBK Peph SPNBK RELATIVE ABUNDANCE OF -- -. 1- - . .. . ,. . . .. - - .. .. - COMBUSTION PARTICLES TYPES BY SIZE, EXPRESSED AS PARTICLE DIAMETER SlZE CLASS, WlTH SAMPLE DEPTH IN CORE

SPCBK - spheroldal carbonaceous black Psph - pleurospheretyp chbloc - charcoal blocky chlath - charcoal lath SPNBK spheroldal non-black (simple) cmRN cornbuslion generi~rounded

Chan 1 SPCBK HSP Charî 3 chbloc HSP Chart 4 chlath HSP Charl5 SPNBK HSP 237 elevation of approximately 70 metres, while Pond 5 is less than 5 metres above sea level.

However, 1do not hwe enough data on other site factors here to draw conclusions, and this is a subject for future work.

On a different scale, Pacyna and Shaw (1990) describe very long-range transport of air masses containing natural and anthropogenic pollutants to the Arctic. They distinguish regional pollution in arctic air masses on the bais of elevation: anthropogenic sources closer to the Arctic are more likely to contribute pollutants to layers below 3.5 km, whereas pollutants found at elevations above this represent more distant sources. including Asian deserts (Le. Gobi Desert). Ottar et al. (1986) found patchy areas of polluted air in the Arctic between 1.5 and 4.5 km altitude, with sources kom similar temperature regimes below this.

The episodic nature of this transport may be siD@ficant in environmental terms.

As discussed in Chapter 5, at Hawk Lake, Welch et al. (1991) estimated that 4000 tonnes of dust and other particdates were deposited in a single "brown snow" event in Keewatin, in the Canadian Central Arctic. This dust contained: "diatomsl pollen (Alnzrs sp., PepZis sp. ), chrysophyte cysts, soi1 fungi, sponge spicules, woody and Sphagn ttrn sp. tissue, numerous spherical soot particles", which, on the basis of back trajectory and other analyses. was attnbuted to Asian desert sources. Most significantiy, they found that this single event transferred on the order of 1.O kg of polycyclic aromatic hydrocarbons (PAH) and 0.03 kg of polychlorinated biphenyls (PCB) to the region, arnounts which could account for a significant fraction of the annual accumulation in Wawk Lake, perhaps 25% or more (Welch et al., 199 1). This raises the question of the relative importance of violent 238 storrn events in the transfer of combustion-related particulates. As discussed in Chapter 6,

Hermansen (1990) wites about the impacts on sediment patterns of storrns travelling from the Great Lakes to the Belcher Islands. According to Olson et al- (1 W8),long-range dust events are frequent.

It may be usehl to conceptualize two different types of atrnospheric transport in the Arctic on the basis of the energy invotved for purposes of understanding large particle transport and deposition. The first type of transport is the gradua! movement of the aged aerosols reported in much of the literature from studies of arctic haze, which tend toward uni- or bi-modal distributions (such as those described by Shaw, 1984 and 199 1). The second type is the higher energy episodic event, characterized by unique combinations of particle types, wider ranges of particles sizes and greater numbers of particles in larger size ranges, such as the black snow discussed by Brimblecombe et al. (1 986), and the brown snow described by Welch et al. (1991). Shaw (1980) also describes a similar Iiigh- energy dust event recorded in Hawaii.

In the sediment samples analysed in this study. I generally found the increase in abundance of combustion particles in more recent sediments reported by other researchers elsewhere (see Chapter 2). However, it was not always a graduai or regular increase. For example, as discussed in Chapter 5, in Hawk Lake the spheroidal black carbon particles

(one of the subsets composing super group A) first appeared at around 1 1 cm, then disappeared, then reappeared at 7 cm, but at slightly lower level of abundance. It is possible that this 'Tagged" profile of occurrence with depth in the sediment is related to the episodicity of deposition events. Conclusions and Future Work

The ability to define combustion particle types and categories through this classification process has enabled me to analyze the combustion particle records in sediment sarnples from ponds and lakes. It has also made it possible to collect environmenta1 combustion particle data from which patterns can be drawn that reflect the interactions of an array of environmental variables related to combustion particle occurrence. With some knowledge of relevant site and historical factors, I have been able to link some of the patterns 1 have observed with environmental and human factors.

However much remains to be investigated. While 1 have made a preliminary inquiry into the work of Bryson (1966) and of Barry (1967) on the dominance of air masses of different origins previousIy (Terasmae & Weeks. 1978), it is worthwhile to examine this and other models, in relation to the combustion particie record at the transect sites, in the future.

Many of the strongest depositional signais with respect to combustion particles that I found seemed likely to be Local in origin. This would imply that at least in the vicinity of sorne of the stiidy sites, the Arctic has reached the stage of development where local as well as regional, national, and international measures to protect environmental quality may be desirable. At the sarne time, the investigation of particle size cIasses for various particles (for example, Figure 7.16) suggests that background level effects are detectable, and that long-range transport has occurred.

The universe of combustion particles needs further description, and future work with respect to building reference collections is desirable. This would contribute to the 250 development of a capability for what 1 have called a "forensic" approach to documenting combustion particle occurrence related to episodic air mass movement, Ultimately, by increasing Our capacity to describe the variability in particle populations from remote areas, stronger cases for linking them to emission sources can be made.

Most importantly, much additional work is needed to develop Our understanding of the roles combustion particles may play in environmentai change, in relation to toxicity and contaminant transfer. and to impIications of combustion particles for climate change. through effects on albedo, for esarnple.

Based on the work presented here, the overall priorities that 1 recommend for future research are: further development of the combustion particle classification for paleolimnological purposes, analysis of transport models for large particles in light of sedimentary records of occurrence. and intensive field study of site specific factors related to combustion particle occurrence. 25 1 REFERENCES

Alderton, D. H. M,, 1985. Historical monitoring. Monitoring and Assessrnent Research Centre. MARC Report 3 1. University of London: 320 pp.

Alt, B. T., 1985. Atmospheric circulation in the Canadian High Arctic. AM& of Glaciology. 7: 21 3.

Alt, B. T., 1987. Developing synoptic analogs for extreme mass balance conditions on Queen Elizabeth Island ice caps. Climate and Appl. Meteorol. 26: 1605-1 623.

Arnerican Concrete Institute, 1996. Use of fly ash in concrete. American Concreie Institute, Fannington Hills, Michigan. 34 pp.

Arctic Environmental Protection Strategy, 199 1. Arctic Environment, Rovanierni. 45 pp.

Arctic Monitoring and Assessment Program (AMAP). 1998 S. J. Wilson, editors. AMAP Assessment Report: Arctic Pollution Issues. Oslo, Nonvay: Arctic Monitoring and Assessment Program, 1998; 1, Introduction. pp- 1-8.

Arctic Monitoring and Assessment Program (AMAP). 1998 D. J. Gregor, H. Loeng & L. A. Barrie (eds).AMAP Assessment Report: Arctic Pollution Issues. Oslo, Nonvay: Arctic Monitoring and Assessment Program, 1998: 3. The influence of physical and chernical processes on contaminant transport into and within the Arctic. pp. 25-1 16.

Arctic Monitoring and Assessment Prograrn (AMAP). 1998 R. Dietz, J. Pacyna & D. J. Thomas, (eds). AMAP Assessment Report: Arctic Pollution Issues. Oslo, Nonvay: Arctic Monitoring and Assessrnent Program, 1998: 7. Heavy metals. pp. 373-524.

Armstrong, D. E., J. P. Hurley, D. L. Swackhamrner & M. M. Shafer, 1987. Role of particle-mediated processes. In R. A. Hites & S. J. Eisenreich (eds). Sources and Fates of Aquatic Pollutants. Washington: Arnerican Chernical Society. 15: 49 1-5 17.

Bacci, P., M. Del Monte, A. Longhetto, A. Piano, F. Prodi, P. Redaelli, C. Sabbioni & A. Ventura, 1983. Characterization of the particulate emission by a large oil fuel fired power plant. Journal of Aerosol Science. l4:557-7l!.

Bailey, 1. H., L. F. Radke, J. H. Lyons & P. V. Hobbs, 1984. Airborne observations of Arctic aerosols II: giant particles. Geophysical Research Letters 11597-400.

Bailey, 1. W., 1938. Ce11 wall structure of higher plants. Journal of Industrial and Engineering Chemistry. 30:40-7. 353 Bailey, 1. W. & T. Kerr- 1935. The visible structure of the secondary wall and its significance in physical and chemical investigations of tracheary cells and fibers. Journal of the Arnold Arboretum. l6:273

BaiIey, 1. W. & M. Et. Vestal, 1937. The orientation of cellulose in the secondary wall of tracheary cells. Journal of the Arnold Arboretum 18 :1 8 5-95.

Bailey, J. G., A. Tate, C. F. K. Diessel & T. F. Wall, 1990. A char morphology system with applications to coal combustion. Fuel 69: 225-39-

Barnes, R. S. & W. R. Schell, 1973. Physical transport of trace metals in the Lake Washington watershed, In CycIing and ControI of Metals, Proc. Conf. Environ. Resour. Columbus, Ohio, 1972: 45-53.

Barrie, L. A., 1985. Atmospherïc Particles: Their physical and chemical characteristics, and deposition processes relevant to the chemical composition of glaciers, Ann. GIaciology. 7: 100-108.

Barrie, L. A., 1986. Arctic air pollution: an overview of current knowledge. Atmos. Envir. 20: 643-63.

Barrie, L. A. & M. J. Barrie. 1990. Chernical components of lower tropospheric aerosols in the High Arctic: sis years of observations. J. Atmos. Chem. 1 1 : 21 1-226.

Barrie, L. A. & R. M. Hoff, 1985. Five Years of air chemistry observations in the Canadian Arctic. Atmos. Envir. 19: 1995-30 10.

Barrie, L. A., D. Fisher & R. M. Koerner, 1985. Twentieth century trends in arctic air pollution revealed by conductivity and acidity observations in snow and ice in the Canadian High Arctic. Atmos. Envir. 19: 2055-2063-

Barrie, L. A., D. Gregor, B. Hargrave, R. Lake, D. Muir, R. Shearer, B. Tracey & T. Bidleman, 1992. Arctic contarninants: sources, occurrence and pathways. The Science of the Total Environment, 132: 1-74.

Barry, R. G., 1967. Seasonal location of the Arctic front over North America. Geographical Bulletin. 9: 79-95.

Bassini, F. & P. Becker, 1990. Charcoal's occurrence in soi1 depends on topography in Terra Firme Forest near Manaus, Brazil. Biotropica 22: 420

Bauhau, J., P. K. Khanna & R. J. Raison, 1993. The effect of fire on carbon and nitrogen mineralization and nitrification in an Australian forest soil. Australian Journal of Soi1 Research. 3 1: 62 1-3 9. 253 Bender, M., 1996- A quickening on the uptake- Nature 38 1 :195- 196.

Bennett, S. He,1967. Methods applicable to the study of both fresh and fixed materials. In R. McClung Jones. Microscopical technique for workers in animal and plant tissues. Hafner Publishers Co., New York: 59 1-677.

Bidleman, T., 1993. Workshop on the Analytical and Environmental Chernistry of Toxaphene. Burlington, Ontario, Feb. 4-6.

Bidleman, T. F., G. W. Patton, M. D. Walla, B. T. Hargrave, W. P. Vass, P. Erikson, B. FowIer, V, Scott & D. J. Gregor, 1989. Toxapliene and other organochlorines in Arctic Ocean fauna: evidence for atmospheric delivery. Arctic. 42307-1 3.

Bidwell, R. G. S., 1974. Plant Physiology. Macmillan Publishing Co., Inc, New York, 643 pp.

Bigg, E. K., 19S0. Cornparison ofaerosol at four baseline atmospheric monitoring stations. Journal of Applied Meteoroloçy 19531-33.

Blatt. H., 1982. Sedimentary Petrology. W.H. Freeman, San Diego, California. 564 pp.

Bolch, W. E., Jr., 1975. Solid Waste and Trace Element Impacts. In A. E. S- Green (ed). CoaI Burning Issues 12: 23 1-48.

Bolton, N. E., J. A- Carter, J. F. Emery, C. Fulkerson, L. D. Hulett & W. S. Lyon, 1975. In S. P. Babu (ed). Trace Element Mass Balance Around a Cod Fired Steam Plant. Trace Elements in Fuel. Anlericm Chemical Society, Washington: 175-87.

Bourgeois, J. C., 1986. A poIlen record from Agassiz Ice Cap, northern Ellesmere Island. Canada. Boreas 15(4): 345-3 54.

Bourgeois, J. C. 1990. Seasonal and annual variation of pollen content in the snow of a Canadian High Arctic ice cap, Boreas. 19513-22.

Bourgeois, J. C., R. M. Koerner & B. T. Alt, 1985. Airbome pollen: a unique air mass tracer, its influx to the Canadian high Arctic. Annals of Glaciology 7:109-116.

Bradley, R- S., F. T. Keimig & H. F. Diaz, 1993. Recent changes in the North American Arctic boundary layer in winter. J. Geophys. Res. 98:885 1-8858.

Bradley, R- S., M. J. Retelle, S. D. LudIarn, D. R. Hardy, B. Zolitschka, S. F. Lamoureux & M. S. V. Douglas, 1996. The Taconite Met I&es Project: a systems approach to paleoclimate reconstruction. J. Paleolim. 16: 97- 1 10. 254 Bradshaw, H. W., K. Tolonen & M. ToIonen, (1994) 1997. HoIocene records of fire from the boreal and temperate zones of Europe, In J. S. Clark, K. Cachier, J. G. Goldammer & B. Stocks (cd). Sedirnent Records of Biomass Buming and Global Change, NATO AS1 Series. Series 1: Global Environmental Change, 51 : 347-366.

Bridgeman, H. A., R. C. Schnell, J. D. Kahl, G. A Herbert & E. Joranger, 1989- A major haze event near Point Barrow, Alaska: anaIysis of probable source regions and transport pathways. Atmos. Envir. 232537-2549-

Bright, D. A., W. T. Dushenko, S. L. Grundy & K. J. Reimer, 1995a. Evidence for short- range transport of polychlorinated biphenyls in the Canadian Arctic using congener signatures of PCBs in soils. Sci. of the Tot. Environ. l6O/l6 1 :X 1-263.

Bright, D. A., W. T. Dushenko, S. L. Grundy & K. J. Reimer, 1995b. Effects of local and distant contaminant sources: polychlorinated biphenyls and other organochlorines in bottom-dweIling animals from an Arctic estuary. Sci. of the Tot. Environ. l6O/I 6 1265- 283.

Brimblecombe. P.. T. Davies & M. Tranter, 1986. Nineteenth century black Scottish showers. Atmos. Envir. 20: 1OS- 1057.

Brooks. J. D. & G. H. Taylor, 1965. Formation of graphitizing carbons from the liquid phase. Nature 206:697-699.

Brosset. C.. 1976. Air-borne particles: bIack and white episodes. Ambio 5: 157-63.

Browne. F.L. (ed), 1958. Theories of the combustion of wood and its control. USDA Forest Service, Forest Products Labratory. Madison, Wisconsin.

Bryson, R. A., 1966. Air masses, streamlines and the boreal forest. Geograph. Bull. (Can.) 8: 228-269.

Bryson, R.A., W.N. Irving & J.A. Larsen, 1965. Radiocarbon and soi1 evidence of former forest in the Southern Canadian tundra. Science 147: 46-48.

Bunce, N.J., 1990. Environrnental Chemistry. Wuerz Publishing, Winnipeg, Manitoba. 327 pp.

Burrells, W., 1977. Microscope Technique. Fountain Press, London, 574 pp.

Byram, G. M., 1957. Sorne principles of combustion and their significance in forest fire behavior. Fire Control Notes l8:47-57. 355 Cachier, H., M. P. Bremond & P. Buat-Menard, 1 9 89. Organic and black carbon aerosols over manne regions of the northem hemisphere. Centre des Faibles Radioactivités, Laboratoire mixte CNRS-CEA, France.

Cachier, H., P. Buat-Menard, M. Fontugne & J. Rancher, 1985. Source tearns and source strengths of the carbonaceous aerosol in the tropics. Journal of Atmosphenc Chemistry 3: 469-459.

Cadle, R, D-,1972. Preface to the Particle Atlas Edition Two. In W. C. McCrone & J. G. Delly, 1973- The Particle Atlas. Am Arbor Science Publishers Inc., Ann Arbor, Michigin. v-vi.

Cadle. R. D., 1975. The ineasurement of airbome particles. John Wiley & Sons Inc., New York, 342 pp.

Cadle, R. D. & J. M. Dasch, 1988. Wintertime concentrations and sinks of atmospheric particulate carbon at a niral location in rural Michigan. Atmos. Envir. 22: 1372- 138 1.

Campbell, A. G., 1990. Recycling and disposa1 of wood ash. Tappi: 141-6.

Carette, C. G. & V. M. Mahotra, 1986. Characterization of Canadian fly ashes and their relative performance in concrete. Energy, Mines and Resources Canada, Ottawa. 48 pp.

Carlson. T. N.,198 1. Speculations on the movement of polluted air to the Arctic. Atmos. Envir. 15: 1473- 1477.

Carpenter, R. L., R. D. Clark & Y. Su, 1980. Fly ash from electrostatic precipitators: characterization of large spheres. Journal of the Air Pollution Control Association. 30: 679-68 1.

Charles, M. J., & R. A. Hites, 1987. Sediments as archives of environmental pollution trends. In R. A. Hites & S. J. Eisenreich (ed). Sources and Fates of Aquatic Pollutants. American Chemical Society: 365-389.

Charles, D. F., & J. P. Smol, 1994. Long term chemical changes in Mes: Quantitative inferences using biotic rernains in the sediment record. In L. Baker (ed), Environmentai Chemistry of Lakes and Reservoirs, Advances in Chemistry Series 237, Amencan Chemical Society, Washington D.C., 627 pp.

Charles, D. F., & D. R. Whitehead (eds), 1986. PaIeoecological investigation of recent Iake acidification: Methods and project description. Research Project 2 174-10, Indiana University, Bloomington, Indiana, 150 pp. 256 Charles, D. F., J, P. Sm01 and D. R. Engstrom, 1994. PaleoIimnological approaches to biological monitoring. In S. L. Loeb & A. Spacie (eds), Biological monitoring of aquatic systems. CRC Press, Boca Raton, Florida. pp. 233-293.

Charles, D. F., R. W. Batterbee, 1. Renberg, H. Van Dam & J. P. Smol, 1989. Paleoecological analyses of lake acidification trends in North Amerka and Europe using diatoms and chrysophytes. In S.A. Norton, S.E. Lindberg and A.L. Page (eds), Acidic precipitation Vol. 4. Soils, aquatic processes and lake acidification. Springer-Verlag, Stuttgart, 207-270.

Charles, D. F., M. W. Binford, E. T. Furlong, R. A. Hites, M. J. Mitchell, S. A. Norton, F. Oldfield, M. J. Paterson, J. P. Srnol, A- J. Utala, J. R. White, D. R. Whitehead & R. J. Wise, 1990. PaIeoecological investigation of recent lake acidification in the Adirondack Mountains, N.Y. J. Paleolim.3 : 295-24 1.

Cheng, R. J., V. A. Mohnen, T. T. Shen, M. Current & J. B. Hudson, 1976. Characterization of particulates from power plants. Journal of the Air Poltution Control Association 26: 787-790.

Cliigier, N. A., 1976. Pollution formation and destruction in flarnes - introduction. In NA. Chigier (ed). Pollution Formation and Destruction in Flarnes. Pergamon Press, Oxford. Prog. Energy Combus. Sci. 1: 3-16.

Chomiak, J.? 1990. Combustion: A study in Theory, Fact and Application. Abacus Press. Cordon & Breach Science Publishers. New York. 464 pp.

Chong, T. M. Y. & K. T. Mattes: 1979. Water supply for the worId's most northern community. Symposium on Utilities Delivery in Northem Regions. March 19-11, 1979. Edmonton, Alberta- Cited in K.J. Reimer & W. W. Wolfe, 1985. CFS Alert Environmental Assessment. Department of National Defence. 44 pp.

Chylek, P., V. Srivastava, L. Cahensli, R. G. Pimick, R. L- Dod, T. Novakov, T. L. Cook & D. Hinds, 1987. Aerosol and graphitic carbon content of snow. J-Geophys. Res. 92:98O 1-9809.

Chylek, P., B. Johnson, P.A. Darniano, K.C. Taylor & P. Clement, 1995. Biomass burning record and black carbon in the GISP2 ice core. Geophysical Research Letters 22(2): 89-92.

Clark, F. R. S. & D. A. RusseIl, 1981. Fossil charcoal and the paleoatmosphere. Nature 290: 428.

Clark, .J. S., J. Lynch, B. J. Stocks & J. G. Goldarnmer, 1998. Relationships between charcoal particles in air and sediments in west-central Siberia. The Holocene 8: 19-29. 257 Clark, J. S. & W. A. Patterson III, 1984. Pollen, "O Pb and opaque spherules: An integrated approach to dating and sedimentation in the intertida~environment. J. Sed. Petrol. 54: 125 1- 1265.

Clark, J. S. & W. A. Patterson III, (1994) 1997. Background and local charcoal in sediments: scales of five evidence in the paleorecord. In J.S. Clark, H. Cachier, J.G. Goldamrner & B. Stocks (ed). Sediment Records of Biomass Buming and Global Change. NATO AS1 Series. Series 1: Global Environmental Change 51: 23-48.

Clark, J. S. & P. D. Royall, 1995. Particle-size evidence for source areas of charcoal accumulation in late Holocene sediments of eastern North Amencan lakes. Quat. Res. 43: 80-9.

Clark, J. S. & P. D. Royall, 1994. Pre-industnal particulate emissions and carbon sequestration from biomass buming in North America. Biogeochemistry 23 : 3 5-5 1.

Clark, J. S., B. J. Stocks, & P. J. H. Richard, 1996. Climate implications of biomass buming since the 19th century in eastern North America. Global Change Biology 2: 433 -442.

Clark, J. S.. H. Cachier, J. G. Goldammer & B. Stocks (eds), (1 994) 1997. Sediment Records of Biomass Burning and Global Change. NATO AS1 Series. Series 1: Global Environmental Change 5 1 : 489 pp.

Clark. R. L., 1984. Effects on charcoal of pollen preparation procedures. Pollen et Spores 26: 559-576.

Clark, R. L., 1982. Point count estimation of charcoal in pollen preparations and thin sections of sediments. Pollen et Spores 24523-535,

Clark, T. S., J. Merkt & H. Muller, 1989. Post-glacial fire, vegetation, and human history on the northern alpine forelands, south-western Germany. Journal of Ecology 77:897-925.

Clarke, A. D., R. J. Charlson, L. F. Radke, 1984. Airborne observations of Arctic aerosol IV: optical properties of Arctic haze. Geophysical Research Letters 1 1:405-408.

Clarke, A. D. & K. J. Noone, 1985. Soot in the Arctic snowpack: A cause for perturbations in radiative transfer. Atrnos. Envir. 19: 2045-2053.

Cloke, M. & E. Lester, 1994. Characterization of coals for combustion using petrographic analysis: a review. Fuel 73: 3 15-330.

Cofer III, W. R., K. P Koutzenogii, A. Kokorin & A. Ezcurra, (1994) 1997. Biomass burning emissions and the atmosphere. In I. S. Clark, H. Cachier, J. G. Goldammer & B. 258 Stocks (ed). Sediment Records of Biomass Burning and Global Change. NATO AS1 Series. Series 1: Global Environmental Change 5 1: 189-306.

Condon, R. G., P. Collings and G. Wenzel, 1995. The best part of life: subsistence hunting, ethnicity, and economic adaptation arnong young adult huit males. Arctic 48: 3 1-46.

Cope, M. J. & W. G. Chaloner, 1980. Fossil charcoal as evidence of past atmospheric composition. Nature 283: 647-9.

Cope, M. J. & W. G. Chaloner, 198 1. A reply to Clark and Russell. Nature 290: 428.

Coste, J. H., 1936. The Nature of the Dispersoids in Country and Town Air. In Transactions of the Faraday Society, Sixty-fourth General Discussion of the Faraday Society, The University Press, Aberdeen: 1 162- 11 7 1.

Cumming, B. F., K. A. Davey, J. P. Sm01 & H. J. B. Birks, 1994. When did acid-sensitive Adirondack Iakes (New Yorkt USA) begin to acidie and are they still acidifjhg? National Research Centre, Reprinted frorn the Canadian Journal of Fisheries and Aquatic Sciences. Ottawa, 5 1: 1550-1568.

Cumming, B. F., J. P. Srnol, J. C. Kingston, D.F. Charles, H. J. B. Birks, K. E. Carnburn, S. S. Disit, A- J. Uutala & A. R. Selle. 1992. How much acidification has occurred in Adirondack region lakes (New York, USA) since preindustrial times? Canadian Journal of Fisheries and Aquatic Sciences 49: 128-141.

Cwynar, L. C., 1978. Recent history of fire and vegetation from laminated sedirnent of Greenleaf Lake, Algonquin park, Ontario. Can. J. Bot. 56: 10-2 1.

Daisey J. M., R. J. McCaffrey, & R. A. Gallagher. 198 1. Polycyclic aromatic hydrocarbons and total extractable particulate organic matter in the Arctic aerosol. Atrnos. Envir. l5:1353-1363.

Dallavalle, J. M., 1948. Micromeritics: The Technology of Fine Particles. Second ed. Pitman Publishing Corporation, London, 550 pp.

Davidson, R. L., D. F. S. Natusch, J. R. Wallace & C. A. Evans, Jr., 1974. Trace elements in fly ash: dependence of concentration on particle size. Envir. Sci. Technol. 8:1707-lll3.

Davidson, R. M. & L. B. Clarke, 7996. Trace Elenlents from Coal. IES Coal Research. London. 60 pp.

Davies, C. N., 1974. Particles in the atmosphere - natural and man-made. Atmos. Envir. 8: 1069-1079. 259 Davis, M. B., 1998. Retrospective studies. In G.E. Likens (ed) Long-terni studies in ecology: approaches and alternatives. New York: Sprinçer-Verlag: 71-89. de Baar, H. J. W., J. T. M. de Jong, D. C. E. Baker, B. M., 1995. Importance of iron for plankton bloorns and carbon dioside drawdown in the Southern Ocean. Nature. 373: 412-415.

DeIany, A. C., D. W. Parkin, J. J. Griffin, E. D. Goldberg & B. E. F. Reinman, 1967. Airborne dust collected at Barbados. Geoch, Cosmoch- Acta. 3 1: 885-909. de Vernal. A-, A. Larouche & P. J. H. Richard, 1987. Evaluation of Palynomorph concentrations: Do the aliquot and the marker-grain methods yield comparable results? Pollen et Spores 29: 29 1-304.

Dietz. R., J. Pacyna & D. J. Thomas, 1998. Heavy MetaIs. In Arctic Monitoring and Assessment Program (AMAP), AMAP Assessment : Arctic Pollution Issues. Oslo, Nortvay: 1-3 73 -524.

Disit, S. S., A. S. Disit & J. P. Smol. 1992. Assessment of changes in Iake water chemistry in Sudbury area lakes since preindustrial times. Can. J. Fish. Aquat. Sci. 46: 8- 16.

Disit. S. S., A. S. Disit, J. P. Sm01 & W. Keller, 1995. Reading the records stored in the Iake sediments: A method of esarnining the history and estent of industrial damage to lakes. In J.M. Gunn (ed), Restoration and recovery of an Industrial Region, Springer- Verlag, New York, 358 pp.

Dixit, S. S., J. P. Smol, J. C. Kingston & D. F. Charles, 1993. Diatoms: Powerful indicators of environmental change. Environ. Sci. Technol. 26: 23-33.

Djolov, G. D. & D. E. Syrakov, 1979. Pressure and topography effects on long-range air pollutants transport. In Papers Presented at the WMO Symposium on the Long-Range Transport of Pollutants and its Relation to General Circulation Including Stratospheric/Tropospheric Exchanpe Processes. World Meteorological Association. Geneva, Switzerland: 253-25 8.

Djupstrom, M., J. M. Pacyna, W. Maenhaut, J. W. Winchester, S-M Li & G. E. Shaw, 1993- Contamination of arctic air at three sites during a haze event in late winter 1986. Atmos. Envir. 27A: 2999-30 10.

Doubleday. N. C., 1992. Carbonaceous particles in the High Arctic: Linking contaminants and climate? Musk-Ox 39: 93-99. 260 Doubleday, N. C., 1996. Cornons' concems in search of uncornmon solutions: Arctic contarninants, catalysts if change? The Science of the Total Environment 1 86: 169-1 79.

Doubleday, N. C., 1997. Arctic contarninants and the environment. In T. Fleming (ed), The Environment and Canadian Society. Nelson. 85-1 04.

Doubleday, N. C., M. S. V. Douglas & J. P. Smol, 1995, Paleoenvironmental studies of black carbon deposition in the High Arctic: a case study from Northem Ellesmere Island. The Science of the Total Environment 160/161 : 66 1-668.

Douglas, M. S. V., 1989. Taxonomie and ecological characterization of freshwater diatoms from the sediments of 36 High Arctic ponds (Cape Herschel, Ellesmere Island, N.W.T., Canada). M.Sc. Thesis, Queen's University, Canada. 172 pp.

Douglas' Marianne S. V., 1993. Diatom ecology and paleolirnnology of high arctic ponds. Ph.D. Queen's University, Kingston, Ontario. 161 pp.

Douglas, M. S. V. & J. P. Smol, 1999. Freshwater diatorns as indicators of environmental change in the High Arctic. In E.F. Stoermer & J.P. Smol, (eds), The Diatoms: Applications for Environmental and Earth Sciences. Cambridge University Press. Cambridge: 227-244.

Douglas, M. S. V.. J. P. Sm01 and W. Blake, Jr. 1994. Marked post-18th century environmental change in High Arctic ecosystems. Science 266: 4 16-4 19.

Duff, K. E. & J. P. Smol, 1991. MorphoIogical descriptions and stratigraphic distributions of the clirysophycean stomatocysts from a recently acidified Iake (Adirondack Park, N.Y.). J. Paleolimnol. 5: 73-1 13.

Duff, K. E., B. A. Zeeb & J. P. Smol, 1995. Atlas of Chrysophycean Cysts. Kluwer Academic Publ., Dordrecht, the Netherlands. 194 pp.

Dunbar, M. & K. R. Greenaway, 1956. Arctic Canada from the Air. Defence Research Board, Canada, Queen's Printer. 541 pp.

Dyke, A. S., J.Vincent , J. T. Andrews, L. A. Dredge & W. R. Cowan, 1989. The Laurentide Ice Sheet and an introduction to the quatemary geology of the Canadian Shield. In R. J. Fulton (ed), Quaternary Geology of Canada and Greenland. Minister of Supply and Services Canada, Ottawa: 178- 189.

Ebert, L. B., & J. C. Scanlon, 1988. Interrelation of polynuciear aromatic hydrocarbons and carbonaceous matenals. In L. B. Ebert (ed), Polynuclear Aromatic Compounds. American Chernical Society, Advances in Chernistry No. 2 17. Washington, D.C.: 368-382. 26 1 Ebert, L. B., 1985. Chemistry of ençine combustion deposits: Literature review. In L.E. Ebert (ed). Chemistry of Engine Combustion Deposits. Plenum, New York: 3-18.

Ebert L. B., W. H. Davis, Jr., D. R. Mills & J. D. Dennerlein, 1985. The chemistry of intemal combustion engine deposits - 1. Microanalysis, thermogravimetric analysis, and infrared spectroscopy. In Ebert (ed). Chemistry of Engine Combustion Deposits. Plenum, New York: 7 1-99.

Echalar, F., A. Gaudichet, H. Cachier & P. Arta.0, 1995. Aerosol emissions by tropical forest and savanna biomass burning : characteristic trace et ements and fluses. Geophysical Researcli Letters 22: 3039-3042.

Economist, Tlie, 1995. The way to dusty death. The Economist, February 18, 1995: 82- 83-

Electricity Commission, 1932. Report on the measures which have been taken in this country and in others to obviate the emission of soot, ash, grit and gritty particles from chimneys of electric power stations. His Majesty's Stationary, London.

Etiegni. L., A. G. Campbell & R. L. Mahler, 1991. Evaluation of wood ash disposa1 on agricurtural land 1. Potential as a soi1 additive and liming agent. Communications in Soi1 Science and Plant Analysis 22: 243-256.

Faegri, K & J. Iversen, 1989. Testbook of Pollen Analysis. John Wiley & Sons inc., New York, 328 pp.

Fairs G. L. 1943. The use of the microscope in particle size analysis. Chemistry and Industry: 374-8.

Fairs. G. L.' 1957. Devçlopments in the technique of particle-size analysis by microscopical esamination. The Faraday Society. Transactions of the Society: 209-222.

Filion, L., 1984. A relationship between dunes, fire and climate recorded in the Holocene deposits of Quebec. Nature 309543-6.

Filion, L., D. Saint-Laurent, M. Desponts & S. Payette, 199 1. The late Holocene record of aeolian and fire activity in northem Quebec, Canada. Tlie Holocene 1 201-207.

Fisher, G. L., D. P. Y. Chang & M. Bruinmer, 1976. Fly ash collected from electrostatic precipitators microcrystalline structures and the mystery of the spheres. Science 192: 553- 555. 262 Fisher, G. L., C. E. Chrisp & W. G. Jennings, 1978a. Physical and chemical properties of rnutagens in coal fly ash. In D.D. Hemphill (ed).Trace Substances in Environmental Health. University of Missouri, Missouri: 293-298.

Fisher, G. L., B. A. Prentice, D. Silberman, J. M. Ondov, A. H. Biermann, R. C. Ragaini & A. R. McFarland, 1978b. Physical and morphological studies of size-classified coal fly ash. Environ. Sci. Technol. 12: 447-451.

Florian, M. E., 1990. Scope and history of archaeological wood, In R. M. Rowell & R. J. Barbour (eds), Archaeological Wood. American Chemical Society, Washington: 3-32.

Folger. D. W., 1970. Wind transport of land-derived mineral, biogenic? and industrial matter over the North Atlantic. Deep-Sea Research 17: 33 7-3 52.

Fortescue, J. A. C. & G. G. Marten, 1970. Micronutrients: Forest ecology and systems analysis. In D. E. Reichle (ed) Analysis of Temperate Forest Ecosystems. Springer- Verlag, New York. 173- 198.

Fosberg, M. A. & S. Levis, 1994. Reconstruction of paleo-fire through climate and ecosystems models. In 1. S. Clark, H. Cachier, J. G. Goldammer & B. Stocks (ed). Sediment Records of Biomass Buming and Global Change. NATO AS1 Series. Senes 1: Global Environmental Change 5 1 : 49-70.

Fredskild, B., 1973. Studies in the vegetational history of Greenland. Palaeobotanical investigations of some holocene lake and bog deposits, Bd 198, Nr 4, Reitzels Forag, Copenhagen. 245 pp.

Fredskild, B., 1984. Holocene palaeo-winds and climatic changes in West Greenland as indicated by long distance transported and local pollen in lake sediments. In N. A. Momer & W. Karien (eds.) Climatic Changes on a yearly to miilennial basis. D. Reidel Publishing Company: 163-1 71.

Fyfe, W. S., 1993. The life support system in danger: Challenge for the earth sciences. Earth Science 47(3): 179-20 I .

Gajewski K., S. Payette, J. C. Ritchie, 1993. Holocene vegetation history at the boreal-forest - shb-tundra transition in north-western Quebec. Journal of Ecology 8 1: 43 3-443.

Garstang, M., P. D. Tyson, H. Cachier & L. Radke, (1994) 1997. Atmospheric transports of particulate and gaseous products by fire. In J.S. Clark, H. Cachier, J.G. Goldarnmer & B. Stocks (ed). Sediment Records of Biomass Buming and Global Change. NATO AS1 Series. Series 1: Global Environmental Change 5 1: 207-52. 263 Gatz, D. F,, 1975. Relative contributions of different sources of urban aerosols: application of a new estimation method to multiple sites in Chicago. Atmos. Envir. 911-18.

Gay A. J., R. F. Littlejohn, P. J. Van Duin, 1984. Studies of carbonaceous cenospheres from fluidised-bed combustors. The Science of the Total Environment 36: 239-46.

Giever, P. M., 1968. Analysis of number and size of particulate pollutants. In A.C. Stem, Air pollution, II, Academic Press, New York: 249-279.

Glew, J. R., 1988. A portable estruding device for close interval sectioning of unconsoIidated core sarnples. J. Paleolirn. 1: 235-239.

Glew. J. R., 1989. A new trigger rnechanism for sedirnent samplers. J. Paleolim. 2: 241 - 243.

Glew. J. R.. 199 1. Miniature çravity corer for recovering short sediment cores. .J. Paleolim. 5: 285-287.

Goldberg, E. D.. 1985. Black carbon in the environment. J. Wiley & Sons Inc., New York, 198 pp-

Goldstein. H. L. & C. W. Siegmund, 1976. Influence of heavy fuel oil composition and boiler combustion conditions on particulate emissions. Envir. Sci. Technol. 10:1109-1114.

Goodlad, J. 1995. Effects of the Braer oilspill on the Shetland seafood industry. Presentation to International Conference on Marine Marnmals and the Marine Environment, North Atlantic Marine Mammal Commission, Lerwick, ShetIand. April20-21, 1995.

Graedel, T. E., T. S. Bates, A. F. Bouwman, D. Cunnold, J. Dignon, 1. Flung, D. .J. Jacob, B. K. Lamb, J. A. Logan, G. Marland, P.Middleton, J. M. Pacyna, M. Placet & C. Veldt, 1993- A compilation of inventories of ernissions to the atmosphere. Global Biochemical Cycles 7(1): 1-26.

Grasserbauer, M., 1978. Characterization of individual airborne particles by light microscopy, electron and ion probe microanalysis, and electron microscopy. In H. Malissa (ed). Analysis of Airborne Particles by Physical Methods. CRC Press Ltd, West Palm Beach, Florida: 1X- 178.

Gray, D. R., 1997. AIert, Beyond the Inuit lands: The story of the Canadian Forces Station Alert. Borealis Press, Ottawa, 197 pp. 264 Green, A. E- S. (ed), 1980. Coal Burning Issues- University Presses of Florida, Gainsville, 390 pp.

Green, H. 1946. Two dimensional form of flocculation. Industrial and Engineering Chernistry. 3 8:679-882.

Green, H. L., 1936- The size frequency of particles in minera1 dusts. In Transactions of the Faraday Society, Sisty-fourth General Discussion of the Faraday Society, The University Press, Aberdeen: 109 1-1 097.

Greenatvay, K., C. Beattie, R. Cameron, N. Doubleday, P. Gravel, J. Halstead, F. Harnpson, S. Hazell, D. Pharand, G. Robertson, F. Roots, C. Tucker, A. Saunders & E. Solem, 199 1. The Arctic Environment and Canada's International Relations, Canadian Arctic Resources Cornmittee, Ottawa: 83 pp + append.

Gregor, D. J., 1990. Deposition and accumulation of selected agricultural pesticides in Canadian Arctic snow. In D. Kurtz (ed), Long Range Transport of Pesticides. Lewis Piiblishers, Chelsea, Michigan: 373-386,

Gregor, D.J., 199 1. Trace organic chemicals in the arctic environment: atmospheric transport and deposition. In W. Sturges (ed), Pollution of the Arctic Atmosphere. Elsevier Science PubIishers Ltd.: 21 7-254

Gregor, D. J. & W. D. Gummer, 1989. Evidence of atmospheric transport and deposition of orgailochlorine pesticides and polychlorinated biphenyls in Canadian Arctic snow. Environ. Sci. Technol. Z:56 1-565.

Gregor, D. J.. H. Loeng & L. Barrie, 1998. The influence of physical and chemicaI processes on contaminant transport into and within the Arctic. In Arctic Monitoring and Assessment Program (AMAP), AMAP Assessment : Arctic Pollution Issues. Oslo, Norway: 25- 1 16.

Gregor, D. J., A. J. Peters, C. Teixeira, N. Jones & C. Spencer, 1995. The historkal residue trend of PCBs in the Agassiz ice cap, Ellesmere Island, Canada. The Science of the Total Environment 160/16 1 : 1 17- 126.

GEUD-Arendal, GRID-Arendal Meta Data Base, Updated July 20, 1999. http://~wv.grida.no/db/maps/prod/level1/70404.htm

Griest, W. H., 1984. Carbonaceous particles and coal combustion stack ash and their interaction with polycyclic aromatic hydrocarbons. The Science of the Total Environment 36: 209-214. 265 Griest, W. H. & B. A. Tomkins, 1984. Carbonaceous particles in coal combustion stack ash and their interaction with polycyclic aromatic hydrocarbons. The Science of the Total Environment 36: 209-2 14.

Griffin, J. J. & E. D. Goldberg, 1979. Morphologies and Origin of Elemental Carbon in the Environment. Science 206: 563-565.

Griffin, J. J. & E. D. Goldberg, 195 1. Sphericity as a characteristic of solids and fossil fuel burning in a Lake Michigan sediment. Geoch. Cosmoch. Acta. 45: 763-769.

Gschwend, P. M. & R. A. Hites, 198 1. Fluxes of PAH to marine and lacustrine sediments in the northeastern United States. Geochim. Cosrnochim. Acta, 44: 2359-2363.

Hallimond, A. F. 1953. Manual of the polarizing microscope. Second edition. Cooke, Troughton & Sirnms, Ltd. York, England, 197 pp.

Hamilton, E. M. & W. D. Jarvis, 1963. The identification of atmospheric dust by use of the microscope. Central Electricity Generating Board, London, 32 pp.

Hamilton, R. J., 1934. The relation behveen free falling speed and particle size of airborne dusts. Paper D4. British Journal of Applied Physics 3, Special Suppl. S90-95.

Hamilton R. J., J. F. Holdsworth & W. H. Walton, 1954. Factors in the design of a microscope eyepiece graticule for routine dust counts. British Journal of Applied Physics 3: 101-105.

Hamilton, R. S. & T. A. Mansfield, 1993. The soiling of materials in the arnbient atmosphere. Atmos. Envir. 27.4: 1369- 1374.

Hardy, D. R., 1996. Climatic influences on strearnflow and sediment flux into Lake C2, northern Ellesmere island, Canada. J. Paleolirn. 16: 133-149.

Hargrave, B. T., W.P- Vass, P. E- Erickson and B. R. Fowler, 1989. Distribution of chlonnated hydrocarbon.pesticides and PCBs in the Arctic Ocean. Can. Tech. Rept. Fish. Aquat, Sci. 164: 224 pp.

Harvey, H. W., 1933. On the rate of diatom growth. Journal of the Marine Biological Association of the United Kingdom 19:253-276.

Harvey, H. W., 1937. The supply of iron to diatoms. Journal of the Marine Biological Association of the United Kingdom 22205-219-

Harvey. H. W., 1939. Substances controlling the growth of a diatom. Journal of the Marine Biological Society of the United Kingdom 23499-520. 266 Havas? M. & Hutchinson T. C., 1983. The Smoking Hills: natural acidification of an aquatic ecosystem. Nature 30 1:23 -27.

Haywood, J. D. & K. P. Shine, 1995. The effect of anthropogenic sulfate and soot aerosol on the clear sky planetary radiation budget. Geophysical Research Letters 22(5): 603-606.

Heckman F- A- & A. 1. Medalia, J. Inst. Rubber Ind- 3: 66

Hedges, J. i., 1990. The chemistry of archaeological wood. In R. M. Rowell & R. J. Barbour (eds), Archaeological Wood. American Chemical Society, Washington D.C.: 11 1-140.

Heicklen, J. (rd). Atrnospheric Chemistry. Acadernic Press, New York: 273 pp.

Hein, .J. W. de B., J. T. M. de Jong, D. C. E. Bddcer, B. M. Loscher, C. Veth, U. Bathmam & V. Smetacek, 1995. Importance of iron for plankton blooms and carbon dioside dracvdocvn in the Southern Ocean. Nature. 3 73 : 4 12-4 15.

Henderson, P. J., 1996. Heavy metal distribution in humus and surficial sediments in the vicinity of a Canadian smelter. Talk given at Carleton University, May 2-3, 1996.

Henderson, P. J., 1. McMartin. G. E. M. Hall, D. Walker, and J. B. Percival, 1995: Mercury distribution in humus and surficial sediments in the vicinity of Flin Flon, Manitoba, Canada. Wat. Air Soi1 Pollut. 80: 1043-1046.

Henderson P. J., 1. McMartin, G. E. Hall, J. B. PercivaI & D. A. Walker, 1998. The chernical and physica1 characteristics of heavy metals in humus and till in the vicinity of the base metal smelter at FIin Flon, Manitoba, Canada. Environmental Geology 3439-58.

Henein, N. A., 1976. . Analysis of pollutant formation and control and fuel economy in diesel engines. In N.A. Chigier (ed), Pollution Formation and Destruction in Flarnes. Pergamon Press, Oxford: 165-208.

Hermanson, M. H., 1990. OP^ and 13'cs chronology of sediments from small, shallow Arctic lakes. Geoch. Cosmoch. Acta. 54: 1443-1451.

Hermanson, M. H., 199 1. Chronology and sources of anthropogenic metals in sediments fiom small, shallow arctic lakes. Envir. Sci. Technol. 25: 2059-2064.

Herdan. G., 1960. Small Particle Statistics. Buttenvorths, London, 41 8 pp.

Hemdon, W. C., 1988. New dimensions in polynuclear aromatic compounds. In L.B. Ebert (ed). Polynuclear Aromatic Compounds. American Chemical Society, Washington: 1-12. 267 Herrick, R. A. & L. G. Benedict, 1968. A microscopic classification of settled particles found in the vicinity of a coke making operation. Air Pollution ControI Association Proceedings: 68-1 37.

Herring, J. R., 1977. Charcoal fiuxes into Cenozoic sediments of the North Pacific. Unpublished PhD. thesis. University of Califomia at San Diego, Califomia. 105 pp. Cited in Goldberg, E.D., 1983. Black carbon in the environment. J. Wiley & Sons Inc., New York, 198 pp.

Heywood, H., 1946. A comparison of methods of measuring microscopical particles. Bulletin of The Institution of Mininç and Metallurgy 477: 1- 14.

Hidy, G. M., W. Green & A. Alkemeeny, 1972. Inadvertent weather modification and Los Angeles smog. In G.M. Hidy (ed)., Aerosols and Atmospheric Chemistry. Academic Press, New York: 339-344.

Hinds, W. C., 1982. Aerosol Technology. John Wiley & Sons, New York. 430 pp.

Hites. R. A. & S. J-Eisenreich (eds). Sources and Fates of Aquatic Pollutants. Washington: American Chemical Society. 15: 49 1-5 17.

Hites, R. A.? R. E. Laflamme & 5. W. Famngton, 1977. Sedimentary polycyclic Aromatic kydrocarbons: The historical record. Science 198: 829-83 1.

Hjelmroos. M., & L. G. Franzen, 1994. Implications of recent long-distance pollen transport events for the interpretation of fossiI pollen records in Fennoscandia. Review of Palaeobotany and Palynology 82: 175-89.

Hoadley, R. B., 1990. Identifiing Wood: accurate results with simple tools. The Taunton Press. Newtom, Connecticut, 223 pp.

Hoffmann, P. & M. A. Jones, 1990. Structure and degradation process for waterlogged archaeological wood. In R. M. Rowell & R. J. Barbour (eds), Archaeological Wood. American Chemical Society, Washington: 3 5-65.

Holdsworth J. F., F. H. Price, & R. C. Tomlinson, 1954. Inter-laboratory checks on the counting of coal dust particles on thermal precipitator slides. British Journal of Applied Physics 3 :96- 10 1.

Holland, A. J. & E. Preston, 1937. The microscopical esamination and identification of crystalline products in commercial glasses. Journal of the Society of Glass Technology 21 : 395-408. 268 Holland, A. J. & E. Preston, 1938. The microscopical esamination and identification of crystalline products in commercial glasses. Part II. Journal of the Society of Glass Technology 283-98.

Hopper, J. F., H. B. Ross, W. T. Sturges & L. A Barrie, 1991. Regional source discrimination of atmospheric aerosols in Europe using the isotopic composition of lead, Tellus 43B: 45-60.

Hom, S. P., 1989, Prehistoric fires in the Chimpo highlands of Costa Rica: sedimentary charcoal evidence. Revista de Biologia Tropical 37: 139- 148,

Hueglin C. H,, C. H. Gaegauf, S. Kunzel & H- Burtscher, 1997. Characterization of wood combustion particles: morphology, mobility and photoelectric activity. Envir. Sci. Technol. 3 1: 3439-3447.

Huttunen, P., 1980. Early land use, especially the slash-and-burn cultivation in the commune of Lammi, southem Finland, interpreted rnainly using pollen and charcoal analyses- Acta Bot. Fennica 1 13: 1-45.

Insley, H., 1924. The rnicroscopic identification of stones in glass. Journal Of the American Ceranlic Society 7: 14-1 8.

Inuit Circumpolar Conference, 1990. Principles and Elements for a Comprehensive Arctic Policy. pp.96

Isaksen, 1. S. A.. 1979. Transport and distribution of pollutants in the troposphere. Papers Presented at the WMO Symposium on the Long-Range Transport of Pollutants and its Relation to General Circulation Including Stratospheric/Tropospheric Eschange Processes. World Meteorological Association, Geneva, Switzerland: 347-58.

Iversen, J. (1 934). Moorçelogische Untersuchungen auf Gronrand. Meddr. Danmarks Geologiske Forehandl. 8: 34 1-358. Cited in W.A. Patterson III, K.J. Edwards & D.J. Maquire, 1987. Microscopie charcoal as a fossil indicator of fire. Quaternary Science Reviews 6: 3-23.

Iversen, T., 1983. On the atmospheric transport of pollution to the Arctic. Geophysical Research Letters 1 1:357-460.

Jaffe, D, A., 199 1. Local sources of pollution in the arctic: from Prudhoe Bay to the Taz Peninsula. In W. T. Sturges (ed), Pollution of the Arctic Atmosphere. Elsevier Science PubIishers Ltd, Barking, Essex: 255-288.

Jensen, J., 1990. State of the Arctic Environment Report on Organochlorines. DIAND, Canada. 269 Johnson, J. P. Jr., 1990. The Establishment of Alert, N WT, Canada. Arctic 43 : 2 1-34.

Jones D.M., W.W. Shilts & R.W. Wein, 1976. Heavy metal content of tundra plant species. Geol. Surv. Cm. Paper 76-IB: 273-9.

Jones, T. P. & W. G. Chaloner, 199 1. FossiI charcoal, its recognition and paleoatmospheric significance. Palaeogeogr. Palaeoclim. PaIaeoecol. 9759-50-

Jones, T. P., W. G. Chaloner & T. A. J. Kuhlbusch, (1994) 1997. Proposed bio-geological and chemical based terminolog for fire-altered plant matter. In J. S. Clark, H. Cachier, S. G. Goldarnmer & B. Stocks (ed). Sediment Records of Biomass Buming and Global Change. NATO AS1 Series, Series 1: Global Environmental Change 51: 9-22,

Jones, V. J., R. J. Flower, P. G. Appleby, J. Natkanski, N. Richardson, B. Rippey, A. C. Stevenson & R. W. Battarbee, 1993. Palaeolimnological evidence for the acidification and atmospheric contamination of lochs in the Caimgonn and Lochnagar areas of Scotland. J. of Ecology 8 1: 3-24.

Keeling, R. F., S. C. Piper M. Heimann, 1996. Carbon trapping by forests in Eastern North America. Nature 3 8 1: 2 18-22 1.

Kellogg, W. W., 1995. Contaminants affecting the Arctic climate, and the role of the oceans. In D. H. Landers. Special Issue: Ecological effects of Arctic airborne contarninants. A collection of papers at the International Symposium on the Ecological Effects or the Arctic Airborne Contaminants, Reykjavik, Iceland. 4-8 October, 1993. The Science of the Total Environment 160- 16 1: 769-776.

Kemp, A. L. W., R. L. Thomas, C. 1. Del1 and J-M. Jaquet, 1976. Cultural impact on the geochemistry of sediments in Lake Erie. J. Fish. Res. Board Can. 33: 440-462.

Kershaw, A. P., M. B. Bush, G. S. Hope, K.-F. Weiss, J. G. GoIdammer & R. Sanford, 1994. The contribution of humans to pass biomass burning in the tropics. In J. S. Clark, K. Cachier, J. G. Goldarnmer & B. Stocks (ed). Sediment Records of Biomass Bwning and Global Change. NATO AS1 Series. Series 1: GIobal Environmental Change 51: 413- 442.

Kingston, J. C., R. B. Cok, R. G. Kreis, K. E. Camburn, S. A. Norton, P. R. Sweets, M. W. Binford, M. J. Mitchell, S. C. Schindler, L. C. K. Shane & G. A. King, 1990. Paleoecological investigation of recent Iake acidification in the northern Great Lakes States. J. Paleolim. 4: 153-20 1.

Koerner, R. M. & D. Fisher, 1982. Acid snow in the Canadian high Arctic. Nature 295: 137-40. 270 Koemer, R. M. & W. S. B. Paterson, 1974. Analysis of a core through the Meighen Ice Cap, Arctic Canada, and its paleoclimatic implications. Quat. Res. 4: 253-263.

Komarek, E. V., P. Carlysle & B. Komerek, 1973. The ecology of smoke particulates and charcoal residues from forest and grassland fires: a preliminary atlas. Ta11 Timbers Research station, TalIahassee, 75 pp.

Krasovskaya, T. M., 1987. Possible routes of transport of atrnospheric pollution into the arctic and patterns of accumulation in snow and ice. Polar Geography and Geology 1 1:76-80.

Krurnbein, W. C. & F. J. Pettijohn, 1938. Manual of Sedimentary Petrography. Appleton Century Crofis, New York, 549 pp.

Kurtz? D. A.. 1990. Long range transport of pesticides. Based on papers presented at the 195th National Meeting of the American Chemical Society, held jointly with the Third Cheniical Congress of North America in Toronto in June 1988. Lewis, Chelsea, Michigan. 462 pp.

Landers, O. H., G. Bangay, H. Sisula, T. Colborn and L. E. Liljelund, (1993) 2995. Airborne contaminants in the Arctic: what cve need to know. Presentation at the International Symposium on the Ecological Effects or the Arctic Airborne Contaminants, Reykjavik. Iceland, 4-8 October, 1993. Sci. of the Tot. Environ. 160/16 1: 84 1-48.

Lau, R. J., 1983. Microstructures of coal fly ash particles. Ceramic Bulletin 6 1 :487-490.

Leavitt, P. R. 1993. A review of factors that regulate carotenoid and chlorophyli dsposition and fossil pigment abundance. J. Paleoiimnol. 9: 109- 127.

Lesch, W. & D. H. Cornell, 1987. The Mineralogy and Morphology of fly ash from South African power stations. In Conference Proceedings, Ash: A valuable resource, Council for Scientific & Industrial Research in Association with the Electricity Supply Cornmittee, Pretoria: 1- 13.

Lessing, R., 1930. The economic value of coal cleaning in relation to the probIem of dust and sulphur emission from chimneys, Fuel in Science and Practice 9: 348-358.

Lewis 1. C. & L. S. Singer, 1988. TherrnaI conversion of polynuclear aromatic compounds to carbon. In LB. Ebert (ed). Polynuclear Aromatic Compounds. Washington: Amencan Chemical Society 16: 269-85.

Lightman, P. & P. J. Street, 1968. Microscopical examination of heat treated pulverized coaI particles. Fuel 47: 7-28. 271 Lim, B. & 1. Renberg, (1994), 1997. Lake sediment records of fossil fuel-derived carbonaceous aerosols from combustion. In J. S. Clark, H. Cachier, J. G. Goldammer & B. Stocks (eds)- Sediment Records of Biomass Burning and Global Change. NATO AS1 Series. Series 1: Global Environmental Change 5 1: 443-462,

Lockhart, W. L-, 1993. Implications of chemical contarninants for aquatic animals in the Canadian Arctic: some review comments. Presentation at the International Symposium on the Ecological Effects or the Arctic Airbome Contaminants, Reykjavik, Iceland, 4-8 October, 1993.

Lockhart, W. L., 1995. ImpIications of chemicaI contaminants for aquatic animals in the Canadian Arctic: some review cornments. Sci- of the Tot. Environ. l6O/l6 1:63 1-64 1.

Lockhart, W. L., P. Wilkinson, B. N. Billeck, R. DaneIIe, D. C. G. Muir, R. V. Hunt, R. Wagemann, B. Hauser & E. Slavacek (1 99 1) 1992. Depositional trends: Iake sedirnents. In J. L. Murray & R. G. Shearer (eds), Environmental Studies No. 68. Synopsis of Research Conducted under the 199 1/92 Northern Contarninants Program. Northern Affairs Program. Department of Indian Affairs and Northern Development.

Lockhart, W. L., P. Wilkinson, B. N. Billeck, G. J. Bninskill, R-V. Hunt & R. Wagemann, 1993. Polycyclic aromatic hydrocarbons and mercwy in sediments from two isolated lakes in central and northern Canada. Wat. Sci. Technol. 28: 43-52.

Lodge, J. P. Jr., 1967. Preface. In W. C. McCrone, R. G. Draftz & J. G. Delly, 1967. The Particle Atlas. Ann Arbor Science Publishers Inc,, Ann Arbor, Michigan, vii-viii.

Lodge. J. P. Ir., 1 993. Summary lecture. Atmos. Envir. 27: 1375- 1376.

Ludlam, S. D., 1996. The comparative limnology of high arctic coastal, meromictic lakes. J. Paleolim. 16: 11 1-131.

Mackay, D. & F. Wania, (1 993) 1995. Transport of contarninants to the Arctic: partitioning, processes and models. In D. H. Landers, Special Issue: Ecological effects of Arctic airborne contarninants. A collection of papers at the International Symposium on the Ecological Effects or the Arctic Airborne Contarninants, Reykjavik, Iceland, 4-8 October, 1993., The Science of the Total Environment 160-161: 25-38.

MacKenzie, D., 1995. Killing crops with cleanliness. New Scientist, 23 September 1995: 4.

Maenhaut, W., P. Cornille, J.M. Pacyna & V. Vitols, 1989, Trace element composition and Origin of the Atmospheric Aerosol in the Nonvegian Arctic. Atmos. Envir. 23: 255 1- 2569. 272 Malissa, H,, 1978 Introduction, In H. Malissa (ed). Analysis of Airborne Particles by Physical Methods West Palm Beach, Florida: CRC Press, Inc-: 1-6.

Masood, E., 1996 Once upon a smoggy day in London town. Nature 38 1: 18 1.

McCartney, H. A., 1994. Dispersal of spores and pollen fiom crops. Grana 33: 76-80.

McClung Jones, R. (ed), 1950. McClung's Handbook of Microscopicai Technique. Third Edition. Paul Hoeber, Inc-New York, 790 pp.

McClung Jones, R- (ed), 1967. McClung's Handbook of Microscopical Technique. Third Edition (Facsimile Edition). Hafner Publishing Company, New York, 790 pp.

McCrone, W. C,,1968. MorphologicaI analysis of particdate pollutants. In A. C. Stern, Air pollution, 11, Academic Press, New York: 28 1-30 1.

McCrone, W. C,,R. G. Draftz & J. G. Delly. 1967. The Particle Atlas. Ann Arbor Science Publishers Inc.. Ann Arbor. Michigan, 406 pp.

McCrone, W. C. & J. G. Delly 1973. The Particle Atlas. Edition Two. Vol. 1-4. Ann Arbor Science Publishers Inc., Ann Arbor, Michigan. 1 138 pp.

McCrone, W. C. & J. G. Delly (1973) 1976. The Light Microscopy Atlas. The Particle Atlas. Edition Two. Vol. 2. Ann Arbor Science Publishers Inc., Ann Arbor, Michigan. pp. 303-570.

McCrone, W. C., J. G. Delly & S. J. Palenik, 1979. Light Microscopy Atlas and Techniques. The Particle Atlas. Edition Two. Vol. 5. AmArbor Science Publishers Inc., Ann Arbor, Michigan. pp. 1 145-1454.

McCrone, W, C., J. A. Brown & 1. M. Stewart, 1980. Electron Microscopy Optical Atlas and Techniques. The Particle Atlas. Edition Ttvo. Vol. 6. Ann Arbor Science Publishers Inc., Ann Arbor, Michigan. pp. 1459-1703.

McGinnes, E. A., Jr., S .A. Kandeel & P. S. Szopa, 1971, Some structural changes observed in the transformation of wood into charcoal. Wood and Fiber Science 377-83.

McMartin, 1. & P. J. Henderson, 1996. Regional distribution of heavy metals in humus and till near a base metal smelter at Flin Flon, Manitoba, Canada. EXPLORE (Newsletter for the Association of Exploration Geochemists) 93: 10-1 1.

McNeely, R. & W. D. Gummer, 1984. A reconnaissance survey of the environmental chernistry in east-central ElIesmere Island, N.W.T. Arctic 37: 210-23. 273 McVeety, B. D. & R. A. Hites, 1988. Atmospheric deposition of polycyclic aromatic hydrocarbons to water surfaces: a mass balance approach. Atmos. Envir. 22: 51 1-36,.

Medalia, A. 1, & F. A. Heckman, 1969. Morphology of aggregates - II. Size and shape of carbon black aggregates from electron microscopy. Carbon 7: 567-82.

Medalia, A. 1. & D. Rivin, 1982. Particulate carbon and other components of soot and carbon black. Carbon 20: 48 1-92.

Melosh, H. J., N. M. Schneider, K. J. Zahnie & D. Latham, 1990. Ignition of global wildfires at the Cretaceous/Tertiary boundary. Nature 343: 25 1-54.

Merrick, D., 1984. Coal Combustion and Conversion Technology. Macmillan, London, 405 pp.

Michel-Lévy, A. & A. Lacroix, 1888. The Michel-Lévy Biref~ngenceChart. OriginaIly published in Les Mineraus des Roches, Paris. Reproduced in W.C. McCrone & J.G. Delly, The Particle Atlas, 1: ix, (1972) 1973, Ann Arbor Science Publishers Inc., Ann Arbor. Michigan..

Miskimmin, B. M. & D. W. Schindler, 1994. Long-term invertebrate community response to tosaphene treatment in two Iakes: 50-yr records reconstructed from Iake sediments. Canadian Jotirnal of Fisheries and Aquatic Sciences 5 1:923-932.

Mitchell, J. M., Jr.. 1956. Visual range in the polar regions with particular reference to the AIaskan Arctic. J. Atmos. Terrest. Physics, Special Supplement: 195-21 1.

Mooney, H. A. & C. E. Conrad, 1978. Fire's effect on physical and chernical properties of cliaparral soils. USDA Forest Service. Washington, DC, 65 pp.

Moore, E. S., 1940. Coal. John Wiley & Sons, New York, 473 pp.

Moore, P. D., 1995. Too much of a good thing. Nature 374: 117- 1 1S.

Mott, R. J. (ed)., 1975. The time perspective in northern ecology: palynology and the history of the Canadian boreal forest. Proceedings of the Circumpolar Conference on Northern Ecology, 155 pp.

Muir, D. C. G.l R.J. Norstrom & M. Simon, 1988. Organoclilorine contarninants in Arctic marine food chains: accumulation of specific polychlorinated biphenyls and chlordane-related compounds. Envir. Sci. Technol. 22: 107 1- 1079. 274 Muir, D. C. G., C. A. Ford, N. P. Grift, D. A. Metner & W. L. Lockhart, 1990. Geographic variation of chlorinated hydrocarbons in burbot (Lofa lofa) from remote lakes and rivers 1 Canada. Arch- Envir. Contam. Toxicol. 19: 530-542.

Muir, D. C. G.. N. P. Grift, C. A. Ford, W. Reiger, M. R- Hendzel& W. L. Lockhart, 1988. Evidence for long range transport of toxaphene to remote Arctic and Subarctic waters from monitoring of fish tissues. Long Range Transport of Pesticides and Other Toxics. Proceedings of the ACS Symposium, Toronto. Department of Fisheries and Oceans, Freshwater Institute, Winnipeg: 2-34.

Muir, D. C. G., N. P. Grift, W. L. LocJd~art,P. Wilkinson, B. N. Billeck & G. J. BrunskiII. 1993. Spatial trends and historicai profiles of organochlorine pesticides in Arctic lake sediments. In D.H. Landers, Special Issue: Ecological effects of Arctic airbome contaminants. A collection of papers at the International Symposium on the Ecological Effects or the Arctic Airborne Contaminants, Reykjavik, Iceland, 4-8 October, 1993.

Muir, D. C. G., N. P-Grifi, W. L. Lockhart, P. Wilkinson, B. N. BilIeck & G. J. Brunskill, 1995. Spatial trends and Iiistorical profiles of organochlorine pesticides in Arctic lake sediments. Sci- of the Tot. Environ. 160116 1:447-457.

~un.sell@Colour, 1994. ~unsell@Soi1 Colour Cliarts, 1994 Revised Edition. Macbeth Division of Kollmorgen instruments Corporation. 405 Little Britain Road. New Windsor, New York 12553

Natusch: D. F. S., J. R. Wallace & C. A. Evans Jr., 1974. Toxic trace elements: preferential concentration in respirable particles. Science 183202-204.

Nichols. H., 1970. Late Quaternary pollen diagrams from the Canadian Arctic barren grounds at Pelly Lake, North Keewatin, N.W.T. Arctic and AIpine Research 243-61.

Nichols, H., P. M. Kelly & J. T. Andrews. 1978. Holocene palaeo-wind evidence from palynology in Baffin Island. Nature 273: 140- 142,

Noone, K. J. & Clarke, A. D. 1988. Soot scavengers measurements in arctic snowfall. Atmos. Envir. 22: 2773-2778.

Norstrom, R. J. & D. C. G. Muir, 1988. Long-range transport of organochlorines in the Arctic and sub-Arctic: evidence from analysis of marine rnammals and fish. In N. W. Schmidtke (ed). Tosic Contamination in the Great Lakes. Lewis Publ. Inc. Chelsea, Michigan: 83-1 12.

Northwest Temtorïes Data Book. 1990/9 1. Outcrop Press. Yellowknife. 238 pp. 275 Norton, S. A., 1986. A review of the chemical record in Lake sediment of energy related air pollution and its effects on lakes. Wat. Air Soi1 Pollrit. 3033 1-345.

Novakov, T., W. Cachier, J. S. Clark, A. Gaudichet, S. Macko, & P. Masclet, (1994) 1997. Characterization of particulate products of biomass combustion. In J. S. CIark, H. Cachier, J. G. Goldammer & B. Stocks (ed). Sediment Records of Biomass Buming and Global Change. NATO AS1 Series. Series 1: Global Environmental Change 5 1: 117-144.

Nriagu, J. O., R. D. Coker & L. A. Barrie, 1991. Origin of sulphur in Canadian Arctic haze from isotope measurements. Nature 349: 142-145.

O'Brien, T. P. & M. E. McCuIIy, The study of plant structure principles and selected methods. Termarcarphy Pty. Ltd., Melbourne, Australia.

Odgaard, B. V., 1993. The sedimentary record of spheroidal carbonaceous fly-ash particles in shallow Danisli Mes. J. Paleolim. 8: 17 1-1 87.

Olson, M. P-, K. K. Oikawa, & A. W. A. MacAfee, 1978. Trajectory mode1 AppIied to the Long-range Transport of Air Pollutants. LRTAP 78-4. Atmosphenc Environrnent Service Air QuaIity Branch. 4905 Dufferin St., Downsview, Ontario. M3H 5T4.

Orr, C- Jr. & J. M. DaIIavalle, 1959. Fine Particle Measurement. Macmillan Co., New York. 353 pp.

Ottar, B., 198 1. The transfer of airborne pollutants to the arctic region. Atmos. Envir. 15: 1439-1445.

Ottar, B., J.M. Pacyna & T.C. Berg, 1986- Aircraft Measurements of Air pollution in the Nonvegian Arctic. Atmos. Envir. 30: 87-1 00.

Outridge, P. M., R- D. Evans, R. Wagernann & R. E. A. Stewart, 1997. Historical trends of heavy metaIs and stable lead isotopes in beluga (DeZphimzpterrrs leztcas) and walrus (Odobenris r-ornarus ronzai-us)in the Canadian Arctic, The Science of the Total Environrnent 203 : 209-2 19.

Pacyna, J. M., (1 993) 1995. The origin of Arctic air pollutants: lessons learned about future research. In D.H. Landers. Special Issue: Ecological effects of Arctic airborne contarninants. A collection of papers at the International Symposium on the EcoIogicaI Effects or the Arctic Airborne Contarninants, Reykjavik, Iceland, 4-8 October, 1993., The Science of the Total Environrnent, 160-16 1: 39-54.

Pacyna, J. M., 199 1. Chemical tracers of the ongin of arctic air pollution. In W.T. Sturges (ed)., Pollution of the Arctic Atrnosphere. Elsevier Science Publishers Ltd, Barking, Esses: 97- 132. 276 Pacyna J. M. & B. Ottar, 1989. Origin of natural constituents in the Arctic aerosol. Atrnos. Envir. 23 :809-8 15.

Pacyna, J, M. & G. E. Shaw, 1990. Arctic Haze and Air Pollution. International Conference on the RoIe of the Polar Regions in the Global Change. proceedings of a Conference held June 1 1- 15, 1990 at the University of Alaska, Fairbanks, II: 674-680.

Pankhurst, R. J., 1979. Biological Identification. University Park Press, Baltimore, 1O4 PP-

Parkin, D- W., D. R, Pliillips, R. A. L- Sullivan & L. Johnson, 1970. Airborne dust collections over the North Atlantic. Journal of Geophysical Research 75: 1782- 1793.

Parrington, J. R., W. H. Zoller & N. K. Aras, 1983. Asian dust: seasonal transport to the Hawaiian Islands. Science 220: 195- 197.

Patrick, J. W., M. J. Sims & A. E. Stacey, 1977- Quantitative characterization of the texture of coke. Journal of Microscopy 109: 137-143-

Patterson, H. S. & W. Cawood, 1936. The detemlination of size distribution in smokes. In Transactions of the Faraday Society, Sixty-fourth General Discussion of the Faraday Society. The University Press, Aberdeen: 1084-2 088.

Patterson. W. A., K. J. Edwards & D. J. Maguire, 1987. Microscopic charcoal as a fossil indicator of fire. Quat. Sci. Rev. 6: 3-23.

Patton, G. W., D. A. Hinckley, M. D. Walla, T. F. Bidleman and B. T. Hargrave, 1989. Airbome organochlorines in the Canadian High Arctic. Tellus 41 B: 243-255,

Patton, G. W., M. D. WaIIa, T. F. Bidleman & L. A. Barrie, 199 1. Polycyclic aromatic and organochlorine compounds in the atmosphere of Northem Ellesmere Island, Canada. J. Geophys. Res. 96: 10867-10877.

Paulson, C. A. J. & A. R. Ramsden, 1970. Some microscopic features of By-ash particles and tlieir significance in relation to electrostatic precipitation. Atrnos. Envir. 4:17S-l85.

Pawley, J. B. & G. L. Fisher, 1977. Using simultaneous three colour x-ray mapping and digital-scan-stop for rapid elemental characterization of coaI combustion by-products. Journal of Microscopy 110: 87- 10 1.

Pecache, G. A., 1979. A cornparison between two methods of measuring the concentration of suspended particulates. Papers Presented at the WMO Symposium on the Long-Range Transport of Pollutants and its Relation to General Circulation Including 377 Stratospheric/Tropospheric Eschange Processes. World MeteoroIogical Association, Geneva, Switzerland: 193- 197.

Penner, J. E., R. E- Dickinson & C. A. O'Neill, 1992. Effects of aerosols from biomass burning on the global radiation budget. Science 256: 1432-1434.

Penner, J. E., H. Eddleman & T. Novakov, 1993. Tocvards the development of a global inventory for black carbon emissions. Atmos. Envir. 27A: 1277- 1295.

Phillips, R. W., 1971. Mineral optics: principles and techniques. W. H, Freeman & Company. San Francisco, 239 pp.

P hilpot C. W. (ed), 1968. Mineral content and pyrolysis of selected plant materials. Intermountain Forest Range Esperiment Station. Ogden, Utah.

Piperno, E., 1975. Trace element emissions: aspects of environmental tosico~ogy.in S.P. Babii (ed). Trace Elenlents in Fuel. American Chemical Society, Washington: 192-209.

Prospero, J. M., 1968. Atmospheric dust studies on Barbados. Bulletin American MeteoroIogical Society 49: 645-52.

Pileschel, R. F. & S. A. Kinne. (1993) 1995. PhysicaI and radiative properties of Arctic atinospheric aerosols. In D. H. Landers, Special Issue: Ecological effects of Arctic airborne contarninants. A collection of papers at the International Symposium on the Ecological Effects or the Arctic Airborne Contaminants, Reykjavik, Iceland, 4-5 October, 1 993. The Science of the Total Environment 160- 16 1: 25-3 8.

Raask, E., 1984. Creation. capture and coalescence of mineral species in coal flames. Journal of the Institute of Energy 57: 23 1-39.

Raatz, W. E., 199 1. The clirnatology and meteorology of Arctic air pollution. In W.T. Sturges (ed)., Pollution of the Arctic Atrnosphere. Elsevier Science Publishers Ltd, Barking, Essex: 13-42.

Raatz, W. E. & R. C. Schnell, 1984. Aerosol distributions and an Arctic aerosoI front during AGASP: Nonvegian Arctic. Geophysical Research Letters. 1 1573-6.

Radke, L. F., P. V. Hobbs & 1. H. Bailey, 1984a. Airborne observations of Arctic aerosols 1: characteristics of Arctic haze. Geophysical Research Letters. 1 1: 393-96.

Radke, L. F., P. V. Hobbs & 1. H. Bailey, 1984c. Airborne observations of Arctic aerosols III: origins and effects of aimasses. Geophysical Research Letters 1 1: 40 1-04. 278 Radke, L. F., J. H. Lyons & P. V. Hobbs, 1984b. Airborne Observations of Arctic AerosoIs. II Giant particles. Geophysical Research letters 1 1: 397-400.

Ragaini, R. C., 1975. Characterization of atmospheric aerosols by neutron activation analysis. In H. Malissa (ed). Analysis of Airborne Particles by Physical Methods. CRC Press. Inc. West Palm Beach. Florida: 93- 123.

Rh,K. A., N. F. Lewis, D- H. Lowenthal & D. L. Smith, 1983. Noril'sk only a minor contributor to Arctic haze. Nature

Rahn, K. A., & R. J. McCaffrey, 1979. Long-range transport of pollution aerosol to the Arctic: a problem ivithout borders. Papers Presented at the WMO Symposium on the Long-Range Transport of Pollutants and its Relation to General Circulation Including Stratospheric/Tropospheric Eschançe Processes. World Meteorological Association. Geneva, Switzerland: 25-35.

Rahn. K. A., D. K. Lowenthal & J. M. Harris, 1989. Long-range transport of pollution aerosol from Asia and the Arctic to Okushiri IsIand, Japan. Atmos. Envir. 232597-2607.

Ramsden, A. R., 1968. Application of electron microscopy to the study of pulverized-coal con~bustionand fly-ash formation. Journal of the Institute of Fuel 41: 451-454.

Ranlsden, A. R., 1969. A rnicroscopic investigation into the formation of fly-ash during the combustion of a pulverized bituminous coal. Fuel 48: 12 2 -1 37.

Ramsden, A. R. & M. Shibaoka, 1982. Characterization and analysis of fly-ash particles from coal-fired power stations by a combination of optical microscopy, electron microscopy and quantitative eIectron microprobe analysis. Atmos. Envir. 16: 2 19 1-2206.

Raatz, W. E., 199 1. The Climatology and meteorology of arctic air pollution. In W. Sturges, Pollution of the Arctic atmosphere. Elsevier Science Publishers Ltd., New York: 13-42,

Rab, K. A., R. D. Borys & G. E. Shaw, 1977. The Asian source of Arctic haze bands. Nature 268: 713-715.

Reavie, E. D., J. P. Sm01 & N. B. Carmichael, 1995. Postsettlement eutrophication histories of six British Columbia (Canada) Iakes. National Research Council, Reprinted from Canadian Journal of Fisheries and Aquatic Sciences, Ottawa 52: 2388-240 1.

Reichhert, T., L 996. Regulators face questioning on particulate rules. Nature 380: 1 1-1 2.

Reichle, D. E., 1970. Analysis of temperate forest ecosystems. Springer-Verlag, Berlin, New York, 304 pp. 279 Reimer, K. J. & W. W. Wolfe, 1985. CFS AIert Environmental Assessrnent. Base Construction Engineering OEcer, CFB Trenton, 44 pp.

Renberg. I., 1984. Carbonaceous particles (soot) from fossil fuel combustion. Proc. of a Workshop on Paleolimnological studies of the history and effects of acid precipitation. May 23-25, 1984. Organized by Stephen A. Norton. UNESCO sponsored: 376-386.

Renberg, I., & M. Wik, 1984. Dating recent lake sediments by soot particle counting. Verhandlungen der Internationalen Vereinigung fuer Theoretische und Angewandte Limnologie 22:7 12-7 18.

Renberg, I & M. Wik* 1985a. Soot particle counting in recent lake sediments: An indirect dating method. Ecol. Bull. 37: 53-57.

Renberg, 1. & M. Wik, 1985b. Carbonaceous particles in lake sediments - pollutanrs from fossil fuel combustion. Ambio 14(3): 16 1- 163.

Retelle. M. J., 1986. Stratigraphy and sedimentology of coastal lacustrine basins, Northern EIIesmere Island, N. W.T. Geography Physique et Quaternaire XL: 1 17- 128.

Retelle, M. J. & J. K. Child, 1996. Suspended sediment transport and deposition in a liigh arctic meromictic lake. J. Paleolim. 7 6: 15 1-167.

Ritter. G. J.. 1928. Composition and structure of the ce11 wall of wood. Journal of Industria1 and Engineering Chemistry 20% 1-945.

Ritter, G. J., 1930. Wood Fibers. Journal of Forestry 28533-54 1.

Robins, W. H. M., 1954. The significance and application of shape factors in particle size analysis. Paper D.2. British Journal of Applied Physics 3. Special Suppl. S82-85.

Robinson, J. M., W. G. Chaloner & T. Jones, (1994) 1997. Pre-quaternary records of wildfire. In J. S. Clark, H. Cachier, J. G. Goldarnmer & B. Stocks (ed). Sediment Records of Biomass Buming and Global Change. NATO AS1 Series. Series 1: Global Environmental Change 5 1: 253-270.

Robock, A. & M. Matson, 1983. Circumglobal transport of the El Chichon volcanic dust cloud. Science 22 1: 195-7.

Rose, N. L., 1990. A method for the extraction of carbonaceous particles from lake sediment. J Paleolim. 3 : 45-53.

Rose, N. L., 199 1. Fly-ash particles in lake sediments: Extraction, characterization & distribution. Ph.D. thesis. University of London, London, 290 pp. 280 Rose, N. L., 1993. A note on firther refinements to a procedure for the extraction of carbonaceous fly-ash particles fiom sediments. J. Paleolirnn. 11 :201-204.

Rose, N. L., (1993) 1995. Carbonaceous particle record in Lake sediments from the Arctic and other remote areas of the Northern Hemisphere. In D. H. Landers, Special Issue: Ecological effects of Arctic airbome contaminants. A coIlection of papers at the International Symposium on the Ecological Effects or the Arctic Airborne Contaminants, Reykjavik, Iceland, 4-8 October, 1993., The Science of the Total Environment, 160- 161 : 487-496.

Rose, N. L., 1996. Inorganic fly-ash spheres as pollution tracers. Envir. Pollut. 9 1: 245- 252.

Rose, N. L. & S. Juggins, 1994. A spatiaI relationship between carbonaceous particles in lake sediments and sulphiir deposition. Atmos. Envir. 28: 177-1 83.

Rose, N. L., S. Juggins & J. Watt, 1996- Fuel-type characterization of carbonaceous fly-ash particles using EDS-derived surface chemistries and its application to particles estracted from lake sediments. Proceedings Royal Society of London Series A Mathematical and Physical Sciences 452: 88 1-907.

Rose, N. L., S. Juggins & J. Watt, 1996. Fuel-type characterization of carbonaceous fly-ash particles using surface chemistry. Ambio 23 (4-5): 296-299.

Rose, N. L., P. G. Appleby, J. F. Boyle, A.W. Mackay & R.J. Flower, 1998. The spatial and temporal distribution of fossil-fuel derived pollutants in the sediment record of Lake Baikal, Eastern Siberia. J. PaIeoIim. 20: 15 1-1 62.

Rosen J., 1968. Simultaneous dust and ozone soundings over North and Central Ainerica. Journal of Geophysical Research 73 : 479-486.

Rosen H. & A. D. A. Hansen, 1984. Role of combustion-generated carbon particles in the absorption of solar radiation in the Arctic haze. Geophysical Research Letters 1 1:46 1-4.

Rosen, H., T. Novakov & B. A. Bodhaine, 1977. Soot in the Arctic. Atrnos. Envir. 161 : 1371-1374.

Rosen, K. J. R., W. Chisholm, S. Hong, J.-P. Candelone & C. F. Boutron, 1997. Lead from Carthaginian and Roman and Spanisli mines isotopically identified in Greenland ice dated from 600 B.C. to 300 A-D- Environ. Sci. Technol. 31: 3414-3416.

Rosman, K. J. R., W. ChishoIm, C. F. Boutron, J. P. Candelone & U. Gorlach, 1993. lsotopic evidence for the source of lead in Greenland snows since the late 1960's. Nature 362533-334. 28 1 Rosman, K. J. R., W. Chisholm, S. Hong, J. P. Candelone & C. F. Boutron, 1997. Lead from Carthaginian and Roman Spanish mines isotopicaIIy identified in Greenland ice dated from 600 B.C. to 300 A-D. Environ. Sci. Technol. 3 1: 3414-3416.

Rouse, W. R., 199 1. Impacts of Hudson Bay on the terrestrial climate of the Hudson Bay Lowlands. Arctic & Alpine Res. 23: 24-30.

Rowell, R. M. & R. J. Barbour, (eds) 1990. Archaeological Wood Properties, Chemistry and Preservation. Advances in C hemistry Senes No. 225. Arnencan Chemical Society, Washington, D.C.

Sabbioni, C. & G. Zappia, 1993. Characterization of particles emitted by domestic heating units fùeled by distilled oil. Atmos. Envir. 27A: 133 1- 1338.

Schiener, E. J., 1976. Coal geology. In A. Escher & W. S. Watt (eds), Geology of Greenland. The Geological Survey of Greenland. pp. 506-5 17.

Schlenker, E. H. & M. J. Jaeger, 1980. Health effects of air pollution resulting fiom coal combustion. In A. E. S. Green (ed). Coal Buming Issues: 277-303.

Schnell, R. C.. 1984a. Arctic haze: editorial. Geophysical Research Letters 1 1359.

Schnell, R. C., 1984b. Arctic haze and the Arctic Gas and Aerosol Sampling Program (AGASP). GeophysicaI Research Letters 1 1361-364.

SchneIi, R. C. & W. E. Raatz, 1984. Vertical and horizontal characteristics of arctic haze during AGASP: Alaskan Arctic. Geophysical Research Letters. 1 1 :369-3 73.

Schniewind, A. E., 1990. Physical and mechanical properties of archaeological tvood. In R.M. Rowell & R.J. Barbour (eds), Archaeological Wood. Arnerican Chemical Society, Washington: 87- 109.

Schulz, E. J., R. B. Engdahl & T. T Frankenberg, 1975. Submicron particles from a pulverized coal fired boiler. Atmos. Envir. 9: 1 1 1- 1 19.

Schultz, H., 1993. Size-fractioned measurement of coarse black carbon particles in deposition samples. Atmos. Envir. 27A: 124 1- 1249.

Schultz, H., E. A. Hattman, W. B. Booher, 1975, The fate of some trace elements during coal pretreatment and combustion. In S. P. Babu (ed). Trace Elements in Fuel. American Chemical Society, Washington: 1 39- 153.

Science Research Council, 1976. Combustion-Generated Pollution. Science Research Council, London. 92 pp. 283 Shannon, L. J., P. G. Gorman & M. Reichel, 1971- Particdate Pollutant System Study. Volume II - fine particle emissions. Midwest Research Institute, Kansas City, Missoui

Shaw, G. E., 1980. Transport of Asian desert aerosol to the Hawaiian Islands. Journal of Applied Meteorology 19: 1254-1259-

Shaw, G. E., 1984. Microparticle size spectrum of Arctic haze. Geophysical Research Letters 1 1: 409-412.

Shaw, G. E., 199 1. Physical properties and physical chemistry of arctic aerosols. In W.T. Sturges (ed)., Pollution of the Arctic Atmosphere. Elsevier Science Publishers Ltd, Barking, Esses: 123- 154.

Shaw. G. E., 1993. Long-term ecoIogica1 effects of transport and deposition of atmospheric contaminants in the arctic region. Presented at the International Symposium on the EcoIogical Effects or the Arctic Airborne Contarninants, Reykjavik, Iceland, 4-8 October, 1993.

Shaw, G. E., 1994. Publication prepared for the 1994 European Course on Atmospheres. GrenobIe, France, 26 pp.

Slieath, R. G., M. Havas, J. A. Hellebust & T. C. Hutchinson, 1952. Effects of Ion,- terrn acidification on the algal communities of tundra ponds at the Smoking Hills, N.W.T., Canada. Canadian Journal of Botany 60: 58-72.

Sheridan, P. J., R. C. Schnell & J. D. Kahl, 1990. Individual particle analysis of the springtime Arctic aerosoI, 1983- 1989. International Conference on the Role of the Polar Regions in Global Change. Proceedings of a conference held June 1 1- f 5, 19901 University of Alaska, Fairbanks, II: 708-15.

Simcik, M. F., S. J. Eisenreich, K. A. Golden. S. Liu, E. Lipiatou, D. L. Swackhamer & D. T. Long, 1996. Atmospheric loading of polycyclic aromatic hydrocarbons to Lake Michigan as recorded in the sediments. Envir. Sci. Technol. 30: 3039-3046.

Sly, P. G., 1995. Hurnan impacts on the Hudson Bay Region: present and füture environmental concerns. pp. 171-263. In M. Munawar & M. Luotola (eds), The Contaminants in the Nordic Ecosystem: Dynamics, Processes & Fate. SPB Academic Press, Amsterdam, the Netherlands. 276 pp.

Smith W. H.,. 1974. Air pollution - effects on the structure and function of the temperate forest ecosystem. Envir. Pollut. 6: 11 1- 129. 283 SmoI, J. P., 1986. Chrysophycean microfossils as indicators of lakewater pH. In J.P. Smol, R.W. Batterbee, R-B. Davis and J. Merilainen (eds). Diatoms and Lake Acidity. Dr. W, Junk, Dordrecht, the Netherlands, pp. 275-287,

Smol, J. P., 1990. Are we building enough bridges between paIeoIirnnoIogy and aquatic ecology? Hydrobiologia 21 4: 20 1-206.

Smol, J- P., 1992. Paleolimnology: An important tool for effective ecosystem management. J. of Aquatic Ecosystem Health 1 : 49-58.

Smol, J. P., 1993. Assumptions in Paleolimnology. Notes for Presentation on PaleoIimnology, Department of Bio logy, Queen's University. January 19, 1993.

Smol, J. P., 1995. Paleolimnological approaches to the evaluation and monitoring of ecosystem health: providing a history for environmental damage and recovery, In D. Rapport, C. Gaudet and P. Calow (eds.), Evaluating and monitoring of the health of large scale ecosystems providing NATO AS1 Series, Springer-Verlag, Berlin. 128: 30 1-3 1 8

Smol. J. P. & M. S. V- Douglas. 1996. Long-term environmental monitoring in arctic lakes and ponds using diatoms and other biological indicators. Geoscience Canada, Vol. 23 (4): 225-230.

Smol. J. P., M. S. V. Douglas & R. Pienitz, 1995. Inferring past climatic changes in Canada using paleolimnologica1 techniques. Geoscience Canada, VoI.2 1 (3): 113- 1 18

Smol, J. P., 1. R. Walker & P. R. Leavitt, 199 1. Paleolimnology and hindcasting climatic trends. Verhandlungen der Intemationalen Veringung von Liinnologen 24: 1240-1246,

Sparck, H. & D. Friday, 1988. In B. Stonehouse (ed). Arctic air pollution. Cambridge University Press, Cambridge: 297-3 04.

Stach, E., M.-Th. Mackowsky, M. Teichmuller, G. H. Taylor, D. Chandra & R. Teichmuller. Stach's Textbook of Coal Petrology. Geburder Borntraeger, Berlin 1975. 428 pp.

Stern, A. C., 1976. Air Pollution. Third Edition. Vol. 3: Measuring, Monitoring and Surveillance of Air Pollution. Academic Press, New York. 799 pp.

Stevenson, R. 1983. The morphology and crystalloçraphy of diesel particulate emissions. Carbon. 2O:3 59-365.

Stocks, B. J. & J. B. Kauffman, (1994) 1997. Biomass consumption and behavior of wildland fires in boreal, temperate and tropical ecosystems: parameters necessary to interpret histone fire regimes and future fire scenarios. In J.S. Clark, H. Cachier, J.G. 284 Goldammer & B. Stocks (ed). Sediment Records of Biomass Burning and Global Change- NATO AS1 Series. Series 1: Global Environmental Change, 5 1: 169-188.

Stockmarr, J., 1971. Tablets with spores used in absolute pollen analysis. Pollen et spores 13: 615-621.

Steen-Egli, P., T. M. Potter, J. D. Leonard & R. Pocklington, 1997. The identification of black carbon particles with the analytical scanning electron microscope: methods and initial results, The Science of the Total Environment 198: 21 1-23.

Stoker, H. S., 1976. Environmental Chemistry: Air and Water Pollution. Scott, Foresman and Company, Dallas, 233 pp.

Stonehouse. B. (ed.), 1988. Arctic air pollution. Cambridge University Press, Cambridge, 328 pp.

Sturges, W. T. (ed), 1991. Pollution of the Arctic Atmosphere. Science Publishers Ltd, Barking, Essex: 334 pp.

Suffling, R,, 1992. Climate change and boreal forest fires in Femoscandia and Central Canada. Catena Supplement 22: 1 1 1-1 32.

Sugita, S., G. M. MacDonald & C.P.S. Larsen, (1994) 1997. Reconstruction of fire disturbance and Forest succession from fossil pollen in lake sediments: potential and limitations. In J. S. CIark, H. Cachier, J. G. Goldammer & B. Stocks (ed). Sediment Records of Biomass Burning and Global Change. NATO AS1 Series. Series 1: Globai Environmental Change 5 1 : 3 87-4 12.

Suman, D. O., T. A. J. Kulilbusch & B. Lim, (1994) 1997. Marine sediments: a reservoir for bIack carbon and their use as spatial and temporal records of combustion, In J.S. Clark, H. Cachier, J.G. Goldammer & B. Stocks (ed). Sediment Records oFBiomass Burning and Global Change. NATO AS1 Series. Series 1: Global Environmental Change 5 1: 27 1-394.

Swain, A. M., 1973. A History of fire and vegetation in Northeastem Minnesota as recorded in Lake Sediments. Quat. Res. 3: 383-396.

Taylor, A., Brown, R. J. E., J. Pilon & A. S. Judge, 1982. Permafrost and the shalIow thermal regime at Alert, NWT. The Roger J.E, Brown Mernorial Volume. Proceedings of the Fourth Canadian Permafrost Conference. Calgary, Alberta. March 2-6, 198 1. Reprint, 4th Can. Permafrost Conf., Calgary: 12-32.

Taylor, K. C., P. A. Mayewski, M. S. Twinckler & S. 1. Whitlow, 1996. Biomass buming recorded in GISP2 ice core: a record from eastern Canada. The Holocene 6: 1-6. 285 Taylor, K. E., W. L. Chameides & A. E. Green, 1980. Atrnospheric Modification. In A.E.S. Green (ed) Coal Burning Issues. University Presses of FIonda, Gainesville: 203- 230.

Terasmae, J., 1967. Recent pollen deposition in the northeastem district of Mackenzie (Northwest Territories, Canada). Paiaeogeogr, PaIaeoclim, Palaeoecol. 3: 17-27.

Terasmae, J. & N. C. Weeks (Doubleday), 1979. Naturai fires as an index of paleoclimate. Can. Field Naturalist 93 : 1 16-125.

TimbreIl, V., 1954. The teminal velocity and size of airborne dust particles- Paper D3. Brit. J. Applied Physics 3, Special Suppl. S86-90.

Tolonen, M., 1978. Paleoecology of annually laminated sediments in Al-ivenainen, S. Finland. 1. Pollen and charcoal analyses and their relation to human impact. Annales Botanici Fernici 15: 177-208.

Tolonen, M., 1985. Paleoecological record of local fire history from a peat deposit in SW Finland. Annales Botanici Fennici 22: 15-29.

Toth, D. J. Br A. Leman, 1975. Stratified lake and oceanic brines: salt movement and time linlits of existence. Limnol. Oceanogr. 20: 7 15-728.

Tranter, M., P. Brimblecombe, T- D. Davies, P. W. Abrahams, 1. BIackwood, A. Fernandes & C. E. Vincent, 1985. Particulates in acidic snows from the Cairngorms, Scotland. Annals of Glaciology 7:

Tucker, C. M. & A. S. Judge, 199 1. An assessrnent of permafrost conditions at three DND airports in Arctic Canada as they pertain to future planning and operations, Department of National Defence Canada, Ottawa. ORAE Report, No. R107.

Tyldesley, J. B., 1973a. Long-range transmission of tree pollen to Shetland: 1. Sampling and trajectories. New Phytologist 72: 175-1 8 1.

Tyldesley, J. B., 1973b. Long-range transmission of tree pollen to Shetland: II. Calculation of pollen deposition. New Phytologist 72: 183-90.

Urone' P. & M. A. Kemey, 1980. Atmospheric Pollution. In A.E.S. Green (ed) Coal Burning Issues. University Presses of Florida, Gainesville: 169-1 86. van der Knaap, W. O., 1987. Long-distance transported pollen and spores on Spitsbergen and Jan Mayen. Pollen et Spores 29(4): 449-454. 286 van der Knaap, VLO., 1988. Deposition of long-distance transported pollen and spores since 7900 B.P. studied in peat deposits fiom Spitsbergen. Pollen et Spores 30 (3-4): 409- 416-

Van Krevelen, D. W. 1961. Cod. Elsevier, Amsterdam: 5 14 pp.

Vandegrifi, A- E-, L. J. Shannon, E. W. Lawless, P-G. Gorrnan, E. E. Sallee and M. Reichel, 197 1. Particulate Pollutant System Study. Volume 1 & III - Handbook of emission properties. Midwest Research Institute, Kansas City, Missouri: 384 pp,

Vermaas, D. & P.H. Hermans, 1947. Course of acetylation and deacetylation reactions of cellulose fibers. 1. Optical and swelling properties. Journal of Polymer Science 2: 397- 405.

Wadleigh, M. A., 1997. The arctic atrhosphere sulphur and trace rnetals. Geoscience Canada 23 : 23 7-244.

Wallén, C. C., 1988. In B. Stoneliouse (ed). Arctic air pollution. Cambridge University Press, Cambridge: 309-320.

Wallis, T. E., 1965. Analytical Microscopy. J. & A. Churchill Ltd., London: 205 pp.

Walsh, J. E., 199 1. The Arctic as a bellwether. Nature 352: 19-20.

Wania? F. & D. Mackay, 1995. A gIobal distribution mode1 for persistent organic chemicals. In D. H. Landers, Special Issue: EcoIogicaI effects of Arctic airbome ~ontamin~mts.A collection of papers at the Intemational Symposium on the Ecological Effects or the Arctic Airbome Contaminants, Reykjavik, Iceland, 4-8 October, 1993., The Science of the Total Environment 160- 16 1: 2 1 1-232.

Wania, F. & D. Mackay, 1993. Global Fractionation and Cold Condensation of Low Volatility Organochlorine Cornpounds in Polar Regions. Arnbio 23: 10-1 8.

Watt, J. D. & D. J. Thorne, 1965. Composition and pozzolanic properties of pulverised fuel ashes. 1. Composition of fly ashes fiom some British power stations and properties of their component particles. Journal of Applied Chemistry 15: 585-594.

Weeks, N. C., 1976. Wildfire Cycling in the Natural Environment: A Key to Paleoclimatic Reconstruction. B-Sc. Thesis, Brock University, Canada. 97 pp.

Weinberg, F. J., 1976. The first half-million years of combustion research and today's burning problems. In N.A. Chigier (ed). Pollution Formation and Destruction in Flames. Prog. Energy Combus. Sci. 1: 17-32. 287 Welch, H. E. 1985. Introduction to limnological research at Saqvaquac, Northern Hudson Bay. Cm. J. Fish. Aquat. Sci. 428: 595-505.

Welch H. E., D. C. G. Muir, B. N. Billeck, W. L. Lockhart, G. J. Brunskill, H. 5. Kling, M.P. Olson, & R.M. Lemoine, 199 1. Brow snow: a long-range transport event in the Canadian Arctic. Environmental Science and Technology 25: 280-6.

Wendland W. M., & R. A. Bryson, 198 1. Northern Hemisphere airstream regions. Monthly Weather Review 109: 255-70.

Whalley, W. B., 1990. Material properties. In A. Goudie (ed), GeornorphoIogical Techniques. Unwin Hyrnan, Boston: 1 1 1- 19,

Wik, M., 1992. Environmental records of carbonaceous fly-ash particles from fossil fuel combustion. Ph-D. Thesis. Department of Ecological Botany, Universiv of Umea, Sweden. 90 pp.

Wik, M. & J. Natkanski, 1990. British and Scandinavian lake sediment records of carbonaceous particles from fossil-fuel con~bustion.Series B: Biological Sciences 327: 3 19-23,

Wik. M. & 1. Renberg, 199 1. Recent atrnospheric deposition in Sweden of carbonaceous particles from fossil-fuel combustion surveyed using lake sediments. Ambio 20289-292.

Wik, M. & 1. Renberg, 199 1. SplieroidaI carbonaceous particles as a marker for recent sediment distribution. Hydrobiologia 2 l4:8 5-90.

Wik, M. & 1. Renberg, 1987. Distribution in forest soils of carbonaceous particles from fossil fuel combustion. Wat. Air Soi1 Pollut. 33: 125- 129.

Wik, M., 1. Renberg, & J. Darley, 1986. Sedimentary records of carbonaceous particles from fossil fuel combustion. Hydrobiologia 143387-394.

Williams, D. J., J. W. Milne, S. M. Quigley & D. B. Roberts, 1989. Particulate ernissions from 'in-use' motor vehicles - II. diesel engines, Atmos. Envir. 23:2647-266 1.

Williams, R. J. H., M. M. Lloyd & G. R. Ricks, 197 1. Effects of atmospheric poIlution on deciduous woodland 1: some effects on Ieaves of "Queï.czrspetraea6 (Mattuschka) Leibl. Envir. Pollut. 257-68.

Winchester, J. W., S. M. Li, S. M. Fan, R. C. Schnell, B. A. Bodhaine, & S. S. Naegele, 1984. Coarse particle soi1 dust in Arctic aerosols. GeophysicaI Research Letters 1 1:995-998. Winkier, M. G., 1985. Charcoal analysis for paleoenvironmental interpretation: a chemical assay. Quat. Res. 23: 3 13-326.

Winkler, M. G., 1994. Sensing plant cornmunity and climate change by charcoal-carbon isotope analysis. Ecoscience 1 :340-345.

Winkler, M. G., (1994) 1997. Late Quartenary climate, £ire and vegetation dynarnics. In J.S. Clark, H. Cachier, J.G. Goldammer & B. Stocks (eds). Sediment Records of Biomass Burning and Global Change. NATO AS1 Series. Series 1: Global Environmental Change 51: 329-346.

Wolff, G. T., 1985. Characteristics and consequences of soot in the atrnosphere. Environment International 1 1 :259-269.

Wolfkam, H. G., 1924. Effect of zirconia in enameIs for sheet steel. J. Amer. Ceramic SOC.7: 1-13.

Wong, M. P., 1985. Chernical Residues in Fish and Wildlife Harvested in Northern Canada. Environmental Studies No. 46. Ottawa, Canada. Northern Affairs Program, DINA.

Xiao, J., S. C. Porter, Z. An, H. Kumai & S. Yoshikawa, 1995. Grain size of quartz as an indicator of winter monsoon strength on the Loess Plateau of Central China during the last 130.000 yr. Quat. Res. 4332-29-

Zepp, R. G. & S. A. Macko, (1994) 1997. Polycyclic Aromatic Hydrocarbons in Sedimentary records oFBiomass burning. In J. S. Clark, H. Cachier, J. G. Goldammer & B. Stocks (ed). Sedirnent Records of Biomass Burning and Global Change. NATO ASI Series. Series 1: Global Environmental Change 5 1 : 145- 168.

Zolitschka, B., 1996. Recent sedimentation in a high arctic lake, northern Ellesmere Island, Canada. J. Paleolirn. 16: 169-1 86. 289 APPENDIX 1 PARTICLE CATEGORY CODES FOR INTERPWTATION OF SPREADSHEETS

Particle Code Particle Type

spheroidal opaque simpie SPCBK spheroidal carbonaceous black SPCBR spheroidal carbonaceous bro wn SCPBK(R) spheroidal carbonaceous black(Red-AxP)

Csph cenosp here

spheroidal nonopaque simple transparent, translucent SPNBK spheroidal noncarbonaceous non-black SPYL spheroidal noncarbonaceous yellow SPBR spheroidal noncarbonaceous brown SPRED spheroidal noncarbonaceous red SPRSRD spheroidal, resinous

Psph pleurosphere

chtyP charcoal-type chtot charcoal total

chbloc charcoal, blocky chang charcoal, angular c hlath charcoal, lath charnor charcoal, amorphous chroun charcoal, rounded chlacy charcoal, lacy

combustion opaque coalchar coal char = cmanop dtw diesel type = cmarnop NSPCBK non-spherical combustion black cmlacy combustion, Iacy cmarnop combustion, arnorphous opaque cmRX combustion, amorphous cmanop combustion, angular, opaque combustion, rounded opaque

combustion, rounded, amorphous

power plant type = cmrnix acrcsp acicular spheroidai = cmnop acicm acicular rnass = cmnop cmNOP combustion nonopaque cmmix combustion, amorphous, mixed cmnop combustion, amorphous non-opaque cmangmix combustion angular? mixed opaquehon- opaque

non-carbonaceous shards, crystals associated with combustion glrod glassy rods coal not combustion, but may be associated CtY P coal type cbloc coal blocky cang coal angular cm coal rounded APPENDIX 1 KEY 70 PARTICLE CODES FOR OPERATIONAL CATEGORIES SITES 8 ORIGINAL PARTICLE CATEGORIES

1 spheroidal - opaque - simple 1 1 SPCBK spheroidal carbonaceous black black xxxxx x x x 1 1 SPCBR spheroidal carbonaceous brown brown x spheroidal carbonaceous black (Red-AxP) 1 1 SCPBK(R) black to red (AxP) x x

2 Csph cenosphere black X X

B Spheroid - nonopaque = Group 3 + Group 4 3 spheroidal - nonopaque - simple 3 transparent, translucent coloured or colouriess 3 1 SPNBK spheroidal noncarbonaceous non-black variable, non-black x x xx x x x 3 2 SPYL spheroidal noncarbonaceous yellow yellow x 3 3 SPBR spheroidal noncarbonaceous brown brown x 3 4 SPRED spheroidal noncarbonaceous red red 3 5 SPRSRD spheroidal, resinous red (AxP) x

4 Psph pleurosphere variable, non-black x xxx

C blomass = Group 7 = Type 7.1 + Type 7.2 + Type 7.3 + Type 7.4 + Type 7.5 + Type 7.6 7 cht~P charcoal-type - x x x x 7 chtot charcoal total

7 1 chbloc charcoal, blocky brown to black 7 2 chang charcoal, angular brown to black 7 3 chlath charcoal, lath brown to black 7 4 chamor charcoal, amorphous brown to black 7 5 chroun charcoal, rounded brown to black 7 6 chlacy charcoal, lacy brown to black

5 generic cornbustlon - opaque = combustion sp.= Group 5 = Type 5.1 + Type 5.2 + Type 5,3 + Type 5.4 + 5 cmOp= combustion opaque 5 coalchar coal char = crnanop x x 5 dty P diesel type = cmamop x x I APPENDlX 1 KEY TO PARTICLE CODES FOR OPERATIONAL CATEGORIES 1 SITES 8 ORIGINAL PARTICLE CATEGORIES

5 1 cmlacy combustion, lacy black x 5 2 cmamop combustion, amorphous opaque black x xx x x 5 3 cmRX combustion, amorphous opaque to red (AxP) x 5 4 cmanop combustion, angular, opaque black xx x x

55 cmUN combustion, rounded opaque black 5 6 cmRN(RX) combustion, rounded, amorphous opaque to red (AxP)

E generic combustion - nonopaque = Group 6 = Type 6.1 t Type 6.2 t Type 6.3 t Type 6.4 6 PPt power plant type = cmmix x 6 acicsp acicular spheroidal = cmnop x 6 acicm acicular mass = cmnop x x 6 1 cmNOP combustion nonopaque 6 2 cmmix combustion, amorphous, mixed opaquelnonopaque x x x 6 3 cmnop combustion, amorphous non-opaque x x combustion angular, mixed opaquelnon- 6 4 cmangmix opaque black-variable x

coal - not combustion CtY P coal type cbloc coal blocky cang coal angular cRN coal rounded glrod glassy rods 293 APPENDIX 3.1. SYNOPTIC KEY TO COMBUSTION PARTICLES

(Note: The following is am artificial classification system and key to combustion particles created for purposes of t6is study as set out beloiv. See Chapter 3 for a discussion of the context ivithin which this key \vas developed. It is intended primarily to describe in an orderly and abbreviated fashion the array of combustion particies encountered in this study. )

Part 1. Purpose

The purpose of tliis key is go establish a framework for the description, identification, classification and quantification of the broad class of combustion particles capable of being released into the environment and detected using paIeolirnnoIogicaI techniques and light microscopy. The overall goal is to facilitate study of anthropogenic and natural combustion in the environment. This classification is functional, structural, morphological and artificial in nature and is intended for paleolirnnological work using Iight microscopy. It is not intended to be organic, genetic, phylogenetic or biological in content or structure.

Part 2. Key to Classification of Individual Combustion Particles and Related Material

1. Particle is:

1. a) spherical go to sectian 2.0. 1. b) non-spherica8 go to sectiûn 3.0

2.0. SphericaI Particles

Particle is spherical and non-bioiogicali and

- - ' Organisms such as diatams (Round et al. 1990) and chrysophytes (Sivar, 199 1), siliceous protozoans (Ogdin & Headley, 1980), as well as some vascular plants (Rapp & Mulholland, 1992; Komarek et al. 1973), produce structural elements composed of silica. Chrysophyte cysts, for example, may be spherical, symmetrical, thick-walled, non- crystalline, colourless, transparent or translucent, with or without omamentation (Duff, 1995). Fungi and non-vascular plants may produce spores that are opaque, spheroidal bodies composed of carbon-based molecules. Vascular plants may produce silica bodies called "phytoliths". This classification does not address problems of identification and classification of these biological particles. For an introduction to morphology of chrysophyte cysts see Duff et al. (1995), diatoms see Dixit et al. (1 992) and Round et al. (1990); and for phytoliths. see Rapp & Mulholland (1992) and Pearsall(1987). i) particle is single spliere witliout any discernible features or variations go to section 2- 1. Simple Spheres or ii) particle is Iieterogeneous spliere witli variation in appearance and/or distinguishing external or interna1 features go to section 2.2. Cornplex Spheres

2.1. Simple Spherical Particles

2.1. a) particle is transparent go to section 2.1.1. 2.1. b) particle is translucent go to section 2-12. 2.1. c) particle is opaque go to section 2.1 -3.

2.1.1 - Transparent Splierical Particles

2-1.1 - a) particle appears colourless witli plane polarized light or unpolarized light

2.1.1. b) particle appears coloured witli plane polarized or unpolarized IigIit i) red ii) orange iii) yellow iv) brown V) blue 2.1.1. c) particle appears coloured witIi SI iglitly uncrossed or crossed po larized liglit: i) red ii) orange iii) yellow iv) brown v) blue

2.1 -2. Translucent S plierical Particles

2.1.2. a) particle appears colourless or white witli plane polarized or unpolarized liglit

2.1.2. b) particle appears coloured with plane polarized Iiglit or unpolarized light i) red ii) orange iii) yeliow iv) brown v) blue vi) gray

2.1.2. c) particle appears coloured witli slightly uncrossed or crossed polarized light: i) red ii) orange iii) yelIow iv) brown v) blue vi) gray 2.1.2 d) particle appears white witli sliglitly uncrossed or crossed polarized liglit

2-1.3. Opaque Splierical Particles

2.1.3. a) with plane polarized or unpolarized light, particle appears: i) black ii) brown

2. 1.3. b) witli sliglitly uncrossed or crossed polarized liglit, particle appears: i) black ii) browii iii) red or orange

2.2. Cornples Sphcrical Particles

Particle is spberical and Ilas interna1 structiire and/or external adliesions, and

2.2. a) particle is priiiiarily transparent go to section 2.2.1. 2.2. b) particle is primarily translticent go to section 2.2.2. 2.2. C) particle is primarily opaque go to section 2.2.3.

2.2.1. Transparent Comples Spherical Particles

Particle is transparent, contains iiiclusions consisting of one or more of splieres, gas bubbles or crystals; and/or includes adhesions consisting of splieres or crystals.

Particle appears: 2.2.1. a) colourless witli plane polarized or unpolarized liglit or 2.2. L. b) coloured witli plane polarized or unpoIarized light i) red ii) orange iii) yellow iv) brown v) blue vi) gray and 2.2.1. c) coloured with sliglitly uncrossed or crossed polarized liglit i) red ii) orange iii) yellow iv) brown v) blue vi) gray or 2.2-1. d) less visible witli sliglitly uncrossed or crossed polarized Iight

2.2.2. Translucent Comples Spherical Particles a) Particle appears heterogeneous, witli inclusions andlor adliesions go to section 2.2.2.1.

b) Particle appears Iieterogeneous, but without distinct features go to section 322.2-

2.2.2- 1. a) particle appears primarily white in plane polarized or unpolarized Iight or 2.7.2- 1. b) particle appears primarily coloured in plane polarized liglit or unpolarized liglit i) red ii) orange iii) yeIlow iv) brown v) blue vi) gray

and 2.2.2.1. c) particle appears prin~ariIycoloured with sliglitly uncrossed or crossed po larized 1iglit i) red ii) orange iii) yellow iv) brown V) bliie vi) gray or 2.2.2.1. d) particle is Iess visible with sliglitly uncrossed or Crossed polarized liglit

2.2.2.2. a) particle appears primarily white in plane polarized or unpolarized liglit or 2.2.2.2. b) particle appears primarily coloured in pIane polarized Iiglit or unpolarized 1 ight i) red ii) orange iii) yellow iv) brown v) bIue vi) gray

and 297 2-2-22,c) particte appears primarily coloured witli sliglitly uncrossed or crossed poiarized light i) red ii) orange iii) yellow iv) brown V)blue vi) gray or 22.2.2. d) particle is less visible witli sliglitly uncrossed or crossed polarized liglit

2.2.3. Opaque Complcs Sphericnl Particles

2.2.3. a) particle appears Iieterogeneous, is composed primarily of opaque matter. and displays one or more of tlie following attributes: i) contains many spheres ii) lacy structrire iii) liol low structure iv) associated witli crystal(s) and 2.2.3. b) witli plane polarized or unpolarized liglit, particle appears: i) black ii) brown and 2-23.c) witli sliglitly iincrossed or crossed polarized liglit. particle appears: i) black ii) brown iii) red or orange or 2.2.3, d) particle is less visible witli sliglitly ~incrossedor crossed polarized light

3.0. Non-Spherical Particles

Particle is non-spherical, regular or irregular in shape, and

3.0. a) crystalline and not associated witli other spherical particles

particle is mineral with definite crystalline structure, and is outside the scope of tl-iis investigation

3.0. b) non-crystalline, glassy, or amorplious and

i) opaque go to section 3.1. ii) non-opaque go to section 3.2

iii) mised opaquelnon-opaque go to section 3.3.

3.1. Non-Splierical Opaque Particles

Particle is opaque and

3.1 .a). particle has elements of biological structure and appears charred go to section 3. Charred Biomass Particles (PLATE 1)

3.1 .b) particle is amorplious, Iias vesicles, bubbles, inclusions or other features of combustion products and appears cliarred, but Iias no identifiable biological structure

go to section 5. Generic Combustion Particles (PLATE 4, FIGURES 7 TO 9)

3.1. C)particle tias no combustion features, appears solid and opaque, witIi or witliout traces of bioniass structure go to section 6. Coal-type ParticIes

3.2. Non-opaque Particles

Particle is colourless. glassy, and transparent or translucent, and

i) Iias vesicles. bubbles, incl~isionsor otlier features of combristion products, and may appear partially cliarred, but lias no identifiable biologica1 structure

go to section 5. Generic Comb~istionParticles

3.3. Heterogeneous Opaque and Non-opaque Particles

3.3. a) particle Iias elements of biological structure and appears cliarred go to section 4, Cliarred Biomass Particles

3-3. b) particle Iias vesicles, bubbles, inclusions or otlier features of combustion and appears cliarred, but has no identifiable biological structure go to section 5. Generic Combustion Particles

3.3. c) Particle Iias no biological structure or combustion features go to section 6.Coal-type Particles

3.0. Cliarred Biomass Particles (PLATE I) Particle lias elements of biological structure, appears charred and

4.0. a) appears intact (Le, witliout open networks of pores or skeletal areas composed of ceil walls) go to section 4.1.

4.0, b) Particle structure appears porous or reticulate, displaying networks of pores or skeletal areas cornposed of ceII waIIs go to section 4.2.

4.1. Intact Particles

4.1. a) Sliape is regular, resembling a rectangle go to section 4.1.1.

4.1. b) irregdar go to section 4- 1.3.

CC. 1 -1. Particles witli regiilar sliape: a) widtli to leiigtli ratio less tlian 1 :2, and angles approsimately 90° See PLATE I Figure 7 Category iianie: blocky b) widtli to length ratio eqiial to or greater tlian 1 :2 See PLATE 1 Figure 1 3 Category name: latli

4. I.2. Particles witli irregular sliape, widtli to Iengtli ratio less ttian 1:2; i) irregular polygon witli angles < or > 90" See PLATE 1 Figure 14 Category name: angu Iar ii) indistinct outline, irregiilar proportions, no distingiiisliing features See PLATE 1 Figiire 1 (lower left) Category name: amorphous b) widtli to lengtli ratio less than 12, no distinct angles, rounded polygon See PLATE 8 Figure 13 Category name: rounded

4.2 Cliarred Biomass Particles witli Porous or Reticulate Structure

4-3- a) open tissue structure comprises less than 25% of particle area See PLATE 9 Figure 6 Catesory: Porous

(Note: include Porous Cliarred Bioinass in relevant sliape category for purposes of counting)

4.2. b) open tissue structure comprises greater tlian 25% of particle area giving particle a "lacy" appearance See PLATE 9 Figure 4,s Category: lacy

(Note: treat Lacy Charred Biomass as separate category for purposes of counting)

5. Generic Combustion Particles Non-spherical combustion particle, not readily identifiable as biomass, and is: a) opaque see section 5.1. b) transparent and/or translucent see section 5.2. C) mis of opaque and translucent and/or transparent material see section 5.3.

5- 1. Opaque Generic Combustion Particles

Opaque, non-spherical combustion particle

5.1. a) arnorplious and intact, witliout openings or reticuiation 20 to section 5.1.1. See PLATE 5 Figure 9 5. I .b) reticulated, appearing lacy or porous go to section 5.1 -2. See PLATE 5 Figure 3 5.1.1. particle is ainorpliotis and intact and is

a) angular go to section 5.1.1.1. b) rounded go to section 5-1-12.

5.1 2. reticulate particIe, appears lacy or porous, and i) appears red witli crossed or sliglitly uncrossed polars See Figure Lacy Conibustion (AsP red) See PLATE 5 Figure 14 or ii) no change witli crossed or slightly uncrossed polars See Figure Lacy Combustion See PLATE 5 Figure 4,s

5.1.1.1. angular amorplious combustion particle i) appears red witli crossed or sliglitly uncrossed polars See PLATE 6 Figure 1 Category Angular Amorplious (AxP red) or ii) no change with crossed or sliglitly uncrossed polars See PLATE 6 Figure 7 Category Angular Amorplious

5.1.1.2. rounded amorplious combustion particle i) appears red witli crossed or sliglitly uncrossed polars See PLATE 6 Figure 8 Category Rounded Amorplious (AxP) or ii) no change witli crossed or sliglitly uncrossed polars See PLATE 6 Figure 13 Category Rounded Amorphous

5.2. Transparent and/or translucent combustion particles appearing glassy, amorphous

See PLATE 5 Figure 2 1 Category Non-Opaque Amorphous

5.3. Mis of opaque and transl~icentand/or transparent material, witIi glassy or duII lustre, like slag or char

See PLATE 5 Figure I Category Non-Opaque Amorplious

6. Non-Combustion Particles: Coal-type

6.1. Cod-type Particles Particles witli properties of opacity, transmission of light at edges in red or yellow bands. reaction witIi nitric acid in processing, conclioidal fracturing, fragments esliibiting acute angles, transformation to red or yeIlow hues witli change in degree of polarizatioii of Iight

6.I .a) Coal with regular sliape: i) widtli to Iength ratio less than or equal to 12, and distinct angles approsimately 90° Category name: B Iocky Coal-type ii) rouiided polygon. widtli to lengtli ratio Iess tlian or equal to 1 :2

Category name: Rounded Cod-type

6,I .b) Coal particle sliaped in irregiilar polygon witli distinct angles, no more tlian one angle equal to 90°, and widtli to length ratio less tlian or equal to 12; Category name: Angular Coal-type DOUBLEDAY, N.C. APPLICATION FOR AIR APPROVAL

12. PROCESS FLOW DIAGRMI FOR SAhlPLES (basal on Rosc, N.L , ( 1330) J. Pnlcolimnalogy, 3:JS-53) 1 - 5. for cach saniplc 0.2 g covcr and Icnvc ccntrifiigc rit 2000rpm rinsc walls of tubc and wash -- 7 ' scdinicnt or 0,2 g soi1 or ovcmight for 5 niinulcs at room , rcsiduc i\\lcc \\di11 dislillcd . add 30 ml 6 M WC1 filicr rcsiduc from snow or lempcralurc nlalcr I icc (dncd) is placcd in a I PTFE ccnlrifugc tubc 8A OPTIONAL STEPS FOR 1o. add 30 ml 6M 9. EXCESSWE SILJCA CONTENT 8. 1. add 20 ml 40% HF to tubq cowr lIC1 , transie[ [O 250 ml bcnkcs and 111x11in walcr bath ai 100" C for 3 cool and wasb hoiirs Iiours 8. 2, cool, ccnlrifugc, \snsh and II. ccn(rifugc Iicat on hotplaic ai 8o0c for 2 liaurs

1 I 1 , 12. , r 17. 14, 15. G. add 20niI GM KOH and 1 t prcprtrc slidcs using 1 drop of - add 4 ml 6M KOH and 1 - , 2Srnl30% H2Q2in 5 lcwc ovcrniglil -rvash comniercial mouniing medium aliquots and lei siand ovcr ml bcakcr ml 30%H 2 0; snmplclslidc night

REAGENT VOLUME ESTiMATES (ANNUAL USE) 1. HYDROGEN PEROXJDE - 10 L/YEAR 2. POTASSIUM HYDROXIDE - 2 LA'EAR 3. HYDROCHLORIC ACID - 2 L/YEAR 4. HYDROFLUOFUC ACD - ? 0.5 UY'EAR S. NITRIC ACID - > 1 UYEAR F USED (MYREPLACE STEPS USlNG HYDROGEN PEROXIDE IF PYRITE LEVELS IN SAMPLES ARE I-IIGH

RELATED CBEhfiCAL APPLICATIONS AND VOLUME ESTIMATES (ANNUAL USE) 1. USE 01:SMALL AMOUNTS 01;ACETONE TO CLEAN GLASS (5 WEAR) 2, USE OF MMUTE AMOUNTS OF TOLUEW OR XYLENE TO TlmJ SLIDE MOUNTMG AEDIA (100 MLNEAR) 3, GLAClAL ACETlC AClD OR ETHYL ALCOIIOL OCCASSIONALLY USED FOR SAMPLE DEIiYDMTlON (CSOOMUYEAR OR EACII)

NOTE: VESSELS WlLL BE COVERED AND WASTE REAGENTS WILL HE COLLECTED, NEUTRALIZED WHERE POSSniLE TO MINiMLZE AiR EhIISSIONS APPENDIX 3.3. BRITISH STANDARD GRATICULE COMBUSTION PARTICLE CATEGORY DESCRIPTIONS: PAFtT II AND III

As a result of assembly of the photograpliic atlas of particles, illustrated by Plates 1 to 1 1. the investigation of the combustion reference materials and environmental samples, and the review of literature (discussed in Cliapter 2), key classes of combustion particles have been defined. A brief description of tliese divisions and tlie criteria important for assigning particles to ciasses follows.

Division 1 SpheroidaI Combustion Particles Simple Opaque Spheres (PLATE 2, FIGURES I,2,6 AM) 19; PLATE 11, FIGURE 11) Description: Tliis class consists of unornamented, perfect or nearIy perfect splieres (Plate 2, Figures 1, 2, 6 and 19). Those particles belonging to tliis class, and observable witli tlie light microscope, are generally of diameters in the range of 1 to IO Mm, but occasionally larger particles are seen. Tliese opaque splieres are iisually isotropic, but care is required as anisotropic forms occur. Tlie tistial colour is a deep black, but dark brown to reddish-brown splieres have also been observed. Some opaque splieres appear blue-black (Lessing, 1930). Tliis class is one of the more frequently described classes in the Iiterature, often associated witIi investigations of soot and airborne pollution (Medalia & Riving, 1982). It also appears in tlie coal combustion literature (Raask, 1984). These particles are usrially among tlie smallest sizes of particles, ranging from submicron-sized particles, to 1 to IO [Lm splieres reported in attnosplieric (Parkins et al. 1970, Delaney et al. l967), and in paleoecological studies (Wik, 1985; Rose, 199 1; Odgaard, 1994). Formation of the very tiny (cl pm) black carbonaceous splieres Iias been described in the contest of the osidation of acetytene to prodiice carbon black commercially (Haynes Rr Wagner, 198 1). Esperimental work Iias determined tliat in turbulent diffusion, witli otlier factors being equal. soot production increased with the ratio of carboii to liydrogen in the liquid fuel and with the rate of lieating prior to ignition (Science Researcli CounciI, 1976). However, not al1 simple opaque spheres are carbonaceous. Indtistrial processes, such as snielting, produce opaque splieres tliat are composed of metats and can be emitted to the atmosphere (McCrone & Delly, 1973: Henderson et al. 1997).

Comples Opaque Spheres (PLATE 3, FIGURE 3,5,12,13,14) Description: Tliis class of spherical to splieroidal combustion particles includes a range of opaque spheres with omamentation and/or interna1 structures. Ornamentation may take the form of adliesions of smaIIer spheres or crystals, or fringes of opaque dendritic carbon (see Plate 3, Figure 13). Occasionally amorphorrs material appears welded to the spliere (see Plate 3 Figure 5). Interna1 structures may incltide numbers of very small opaque or non-opaque spheres (see Plate 3, Figure 12) or lacy, convoluted filigree skeletons tliat appear encrusted witli carbon (Plate 3, Figure 4). These particles are primariiy isotropic. Tlie colour is almost invariably a true black. In general, these particles are larger tliat the simpIe opaque spheres, but the size ranges do overlap, with complex lacy splieres as small as 8 pm occurring. Complex opaque spheres as large as 100 or 1 SOpm have been observed in reference material, makiiig this category tlie largest of tlie 305 splierical types seen in tliis study. It lias aIso been observed tliat opaque spheres rnay be hollow, allowing some light to pass by virtue of the tiiinness of the carbon sliell (see Plate 3, Figure 5). Tliese liollow spheres have been termed "cenosplieres" (Fisher et al. 1978). Opaque complex spheres are frequently reported in the literature, as referred to previously, in part apparently because they are relatively common where periodic intense soot emissions occur, as in soot-blowing operations (Hamilton & Jarvis, 1963; Rose, 199 1). They are readily captured in sucli samples, and are likely to be recorded in microscopical samples due to their large size and distinctive appearance. With regard to formation, cenospheres are reported to be formed from both pulverized coal and from heavy oil droplets Iarger tlian 200 Pm,when they are incompletely burned, due to inadequate air supply (Science Researcli Council, 1976).

Simple Non-opaque Spheres Description: (Plate 2, Figures 2 and 5; Plate 3, Figure 7) Particles in this category usuaIIy take the form of perfect spheres, ranging in size from 1 to 1 O Pm. They appear as glassy, translucent or transparent spheres, without ornament or interna1 structure (see Plate 2, Figures 2 and 5). 1 have observed a wide range of colours, including white, yellow, orange, red, brown, and rarely blue or violet, and particles rnay also appear colourless, clear, or milky. Tliese particles have also attracted frequent mention, particularIy in the coal literature, as tliey are primarily, but not esclusively, associated witli minerai constitutents in the coal during corn bustion (Staclis, 19 75). However, tiny "glassy" spheres are also reported from com bustion effluents from diesel and otlier fuels, sucli as peat (Rose & Juggins, 1996). Occasionally tliese tiny. siliceous, non-opaque oil combustion splieres are gold coloured (see Plate 3, Figure 7, for esample). TIiese splieres are formed from rapid cooling of molten glasses and, as sricli, they are espected to be amorpIious in microstructure, and tlierefore isotropie. CVlien examining samples containing tliese spheres under polarized liglit, some simple non-opaque splieres are often birefringent. Sucli birefringence is terined "strain birefringence" (as opposed to true birefringence, whicli is generally due to crystalline or rnoIecular structure), and is attributed to thermal shock, indiiced wlien inolten particles leave the fire zone and cool very rapidly (McCrone & Delly, 1973).

Corn ples Non-opaque Spheres (PLATE 2, FIGURES 9,10,19,20 AND 21) Description: Particles in tliis category are also formed from molten non-combustible mineral material, but unlike the simple non-opaque splieres, the complex non-opaque splieres rnay have a variety of ornaments and surface details, as well as internal structures. Adliesions sucli as srnaller spheres are a result of agglomeration of particles leaving the burner (see Plate 2, Figures 9,10, 19, 20 and 21)- Crystals of hg11 temperatrire minerals, such as mullite, rnay be produced from the molten particle by the sudden cooling as the particle leaves the flame zone. Such crystals have been termed quench crystaIs and rnay be enclosed within the particle or rnay pierce the particle surface (Fisher et al. 1978, Natusch, 1974). Variation in internal structure rnay incltide rnany tiny spheres, in wliich case these particles have been termed pleurosplieres (Fisher et al. 1978). The meclianism proposed by Fisher et al. (1978) for the formation of these complex spheres is interesting: Continued lieating of a droplet causes boiling internally, pushing spherical mini- droplets toward the skin of the droplet, wliere they cool more rapidly, forming mini-spheres witliin tlie larger spliere. Inclusions rnay also be vacuoIes of gases or of liquid produced during the melting of tlie minerals and tlie lieating of the molten mass (see Plate 2, Figure 7 and Plate 4, 306 Figure 12). Cornples splieres may be transparent or translucent, colourless or coloured (see Plate 2, Figure 7). Most are colourless, but some have coloured inclusions that can be yeilow, brown or red, related to iron osides. Tints of green, blue and purple are also occasionally seen.

Rounded Particles: Opaque and Non-opaque (PLATE 4, FIGURES 3,4,5,7,8,9) Description: Unlike splierical particles wliich generally result from a molten liquid, gas or sol id whick has entered the plastic phase and is espanding due to evolved gases, the rounded particles observed are the product of softening or partial melting of primary particles in the combustion process. Tliese particles may have escaped the burning process before being consurned, or they may be relatively incombustible materials tliat have been swept tlirougli tlie flame region and onIy sliglitly altered by Iieat. Such particles may be opaque or non-opaque, as described below. (For example of particles generated by tliis process, see Plate 4, Figures 3,4 and 5, and 7, 8, and 9.)

Rounded Simple Opaque Particles (PLATE 4, TOP OF COMPOUND PARTICLE IN FIGURES 10 AND 11) Description: Ro~indedsimple opaque or non-opaque parricles maybe carbonaceous or composed primarily of metals, in the form of osides or s~ilpliates.Combustion and industrial processes such as smelters can emit these particIes, as can incinerators (McCrone & Delly, 1973). Tliese simple, rounded particles form througli the melting of particles exposed to the fire zone, with the resulting rounding of edges and smootliing of surfaces, but not completely melted or cornbusted, eitlier due to a rapid transit or to a non-combustible composition or to a hi& melting point. As a result tliey are rounded but do not form true splieres (see Plate 4, top of compound particIe in Figures IO and 1 1). Tliese particles may be coinposed of a variety of substances, including carbonaceous material, metals, and plastics, depending on the feedstock and fuel involved.

Comples Rounded Opaque or Non-opaque Particles (PLATE 1, FIGURES 3,4 AND 5; PLATE 5, FIGURES 13,16,17; PLATE 6, FIGURE 13, 15) Description: Complesity in this class refers to the adhesion of other particles to the surface that can be detected in tlie particle profile or by reflected light (see Plate 4, Figures 3, 4 and 5). Cornplex rounded opaque and non-opaque particles rnay Iiave surface adhesions, but unlike the complex spiieroidal particles, tIiey do not contaiti interna1 structures that can be attributed to combustion processes because these particles Iiave been Iieated to varying degrees, but not melted or cornbusted to an appreciabIe extent. It miglit be argued tliat tliese particles, like the others in the "Rounded" super class, are indicators of combustion, ratlier tlian combustion products in the strict sense. However, given the shared origin, transport, deposition and, in some cases, effects, 1 believe it is reasonable to inchde particles of tliis type as combustion particles.

Division II: Non-spheroidal Combustion Particles (PLATE 1, FIGURES 1 TO 16; PLATE 4, FIGURES 7,8,10,11; PLATE 5, FIGURES 1 TO 8; PLATE 6, FIGURES 1,2,7,8,11 AND 12) Description: Non-splieroidal shape is tlie key morpliological feature of tliis division. As a result, a set of categories is included within this division tliat is based on highly variable shape 307 characteristics. It includes combustion products ranging from angular, almost faceted particles; to flocs of material with a crumb-like appearance, to semi-granular material displaying adhesion or cohesion resulting from sintering or quasi-fusion, due to Iieating. It includes non-sphero idal combustion particles displaying interna1 ordering due to a direct biological origin, sucli as particles derived from biornass burning, generally termed cccharcoaI". Biomass rnay also be transformed by cornplex cliemical and physical processes of sequestration and hydrogenation, leading to the formation of petroleurn or coal, which are subsequently burned, and whicli rnay or rnay not retain structural evidence of their biologicai derivation.

Non-spheroidal Biomass Combustion Particles: Charcoal (PLATE 1, FIGURES 1 TO 16; PLATE 8, FIGURES 1 TO 3, AND 11 TO 17; PLATE 9, FIGURES 1 TO 6,8,17 TO 19; AND PLATE IO, FIGURES 16 TO 25) Description: This c lass of biornass combustion particles consists of fragments resu king from wild fire in natural and agricultural ecosystems, and includes forest fire, grassland fire, and tundra fire. In the Arctic, biomass cliarcoal rnay be associated with tundra fires (Bryson and Larsen, I967), with long-range transport of cliarcoal from boreal or temperate forests to tlie south (Nicholls, 1969; Fredskild, 1970), or witli Iiuman activity in recent times. (Tliere are also occasional mentions of tlie use of driftwood for fueI by tlie Inuit in arcliaeological researcli, but this seems to have been restricted in practice.) The cliarcoal particles rnay Vary, as described above, from bIack to dark brown, depending on tlie degree of charring. Emission factors Vary for different biomes, with grasslands producing relatively little cliarcoal. and smoldering boreal forest fires producing cliarcoal emissions several orders of magnitude greater (Stocks and Kauffman, 1994). This subset does not capture tliose spheroidal particles resulting from biomass burning (HuegIin et al. 1997), and so, in tliis sense, is an incomplete or open subset. For esamples of cliarcoal particles, see Plate 1, and Plate 8, Figures 1 to 3, and 1 1 to 17; Plate 9, Figures 1 to 6, 8, 17 to 19; and Plate 10, Figures 16 to 25).

Amorphous Opaque Particles (PLATE 5, FIGURES 8,9,11; PLATE 6, FIGURES 7,12) Description: TIiese particles are amorplious and truly isotropic. Tlieir shapes are irregular. They rnay consist of unstructured (amorphous) carbonaceous particles or true glasses, depending upon wlietlier tliey are formed from carbonaceous or siliceous components of the fiel. Under the microscope, it is possible to separate tliem with top, and sometimes polarized, lighting. Tliese particles rnay result from any of the fuels and burners we have considered.

Amorpho us Carbonaceous Particles (PLATE 2, FIGW 14; PLATE 3, FIGURES 1,2,3; PLATE 6, FIGURES 9, 10) Description: These particles may forrn by agçlomeration of srnaller carbonaceous particles, as in combustion of diesel or other lieavy oils, or by disintegration of larger carbonaceous combustion products such as cenospheres from coal or oil burning. Combustion features rnay be present, depending on the mode of formation. These simple particles tend to be relatively small, ranging from 5 Pm down to the effective Iimit of resolution. Other researchers have noted the presence of similar material: fragments have been described as "crumbs" (Delaney, 1969) and fine material 308 thought to be associated with tlie combustion of fossil fuels has been observed in paIeoecological preparations following digestion of sediments (Wik & Renberg, 1985).

Amorphous Opaque Glassy Particles

(PLATE 2, FIGURES 1,2; PLATE 4, FIGURES da, 6b; PLATE 5, FIGURE 25) Description: Amorphous glassy particles form during coal combustion wlien minerals contained in the coal do not melt completely enough to form spheres, but are plastic and do cool rapidly, resulting in a glass rather than a completely crystalline material. CrystaIs may be associated with these particles. Other fuels, particularly waste products, subject to incineration, may also produce these particles, as rnay catalysts-

Arnorphous Non-opaque Particles (PLATE 2, FIGURES 7,sPLATE 3, PLATE 4, FIGURE 7 - 9; FIGURE 7; PLATE 5, FIGURES 6,12,13,14; PLATE 6, FIGURES 5,6,14) Description: Amorplious non-opaque particles may be translucent or transparent glassy material with indriced stain or crystalline structure, or rnay consist of a mixture of opaque and non-opaque substances.

Mised Opaquemon-opaque Amorphous Partides (PLATE 2, FIGURES 7,8,14; PLATE 3, FIGURE 9; PLATE 3, FIGURE 10,11; PLATE 5, FIGURE 10; PLATE 6, FIGURES 5,6) Description: Particles in tliis category are lieterogeneo~is,appearing opaque and non-opaque, in different regions. Tliese amorplious particles consists of a mixture of the materials found in tlie categories of translucent/transparent and opaque materials described above. 309 APPENDIX 3.5. NON-COMBUSTION CATEGORIES OF INTEREST

TABLE 3.4. NON-COMBUSTION PARTICLE CATEGORIES DEFNED FOR THE PURPOSE OF MAKiNG PARTICLE COWTS FROM ENVIRONMENTAL SAMPLES OF LAKE AND POND SEDIMENT. 10. acicuIar - splieroid + mass acic splieroid acicular spli-acic rnass-acicular mass-ac ic

1 1. power pIant type black, a-p; black to yellow crossed polars

12. coal coal coal angular cang blocky cbloc rounded crnd

13. resinous - re witli crossed polars resr (asp=red) simple sphere resspli comples sphere (cellular testure) Spres(cel1)

14. non-spliere - testiirekel luIar texture APPENDIX 4.1 REPORT ON FIELD WORK AT ALERT

1. Personnel and Field Schedule

The field party consisted of Dr. John Smol, and graduate students Nancy Doubleday and Marianne Douglas, al1 of the Department of Biology, Queen's University. The group anived in Resolute on July 7, left Resolute for Aiert on July 12, and departed Alert on July 23, 1992. The total number of field days available was 17, including 3 travel days.

2. Sampling Objectives

The purpose of this field work was to obtain samples of sediment and water fiom Ponds and lakes; soils and suificial materids; and vegetation fiom Cornwallis Island and fiom the Alert area, Northern Ellesmere Island for use in studies of longrange transport of anthropogenic black carbon and pollen, and in studies of diatoms, water chemistry and toxic contaminants. Preliminary air sarnpling trials were aiso made at Alert.

The information resulting f?om these studies wïli contribute to the fiilfiUrnent of the present contract, to the long-range transport component of the doctoral thesis of Doubleday, as weli as to continuing development of transfer functions for purposes of calibration by &g in important gaps in the large arctic lake data set developed by Smol et al. Assessment of long-term environmental and chnatic change reinains a key focus of this research. Sample materials will also be shared with other investigators.

3. Sarnpling Protocols

The ideal sarnpling protocol included the following measurements and collections at each lake or pond: 1) water temperature - 2) description of site, including estimate of water depth and description of type of drainage 3) rock scrape, ushç a toothbrush 4) phytoplantkon and zooplankton using net tows 5) submerged moss from edge of pond or lake 6) aeropldic rnoss 7) surface sediments 8) bulk sample of submerged moss 9) bulk sample of surface sediment (top 0.5 cm) 10) one or more sediment cores, taken either with a gravity corer or as push cores 11) bulk water samples taken in water at half of the depth of the water column for water chemistry 12) site location according to maps adorGlobal Positionhg System (GSP) 13) bulk soi1 samples for metals and organics 14) veçetation for carbon particulates In addition, conductivity readings were taken, either with depth on site, or fiom the bulk samples on retum to base, pH readings were also taken.

At Aiert ody, an air fltenng site tvas established and maintained in order to gain experience with this type of monitoring, and to coilect some air fiIter samples.

Samples were taken and stored in labelled bottles, vids or whirpacks, depending on the sample type. Sediment cores were usually extruded and sectioned in the field as soon as they were taken, so that rislcs of possible contamination were ininimized.

When bulk water samples were taken for water chemistry, they were subsarnpIed in the field or processed at the base faciIity as soon as possible upon return and sub-sampled for analysis for: chIorophyll a, filtered total phosphorus, unfiItered phosphorus, major ions, trace metals, and dissolved organic carbon. Othenvise, the samples were al1 taken directIy in the field.

4. Sampling Sites

July 7

Arrived at Resolute, Cornwallis Island at approximately 5 PM.

A) CORNWALLIS ISLAND

Many of the sites sampled were within walking distance of the Polar Continental Sheif Project at ResoIute. however PCSP heko~tersupport (to J.P. Sm01 and to D. Gre~or/DT.e;in) made it ~ossible to obtain sarnples fiom a number of more remote sites on Comwaliis as weii. The field party divided up in order to share duties as weI1 as helicopter space in the case of those sites sampled with helicopter support in central and southeast Cornwallis Island. The north-south transect dong the west side of Cornwallis \vas conducted by al1 field party members. Access to Smail Lake was by truck. Access to Meretta Lake was by 4-wheeler. Al1 other sites were reached on foot.

The water and sediment were sampled at the folIowing sites: . 1) Smdl Lake (74"4St465'W.,9S003'874"W.)

July 9

The water and sediment were sampled at the following sites: 2) "Middle Lake" (75'23' N., 94'46' W.) 3) "Pond 1" (74O42' 58.7'W.,95"001 21.5" W.) 4) "Pond 2" (74°42'49.5"N., 9S000'23 -5" W.) The water and sediment were sampled at the following sites: 5) "Pond A and 9 "Bu(75'22' 28" N., 95'37' 50" W.) (Ponds "A" and "B" were approx. 100 m. apari, the GPS reading was taken between them) 7) "Pond C" (75'09' 32" N., 95'12' 13" W.) 8) "Pond D" (75°05' 18" N., 95'09' 11" W.) 9) "Pond E (74"s 8' 46" N., 9S007' 3 4" W.) 10) "Pond F" (74'5 1' 40" N., 95O07' 44"W.)

July 11

The water and sediment were sampled at the foliowing sites: I 1) "Pond 3" (74'42' 48.9" N., 95'00' 44.4" W.) 12) "Pond 4" (74'42' 5 1.9" N., 95'03' 3 1.0" W.) 13) "Pond 5" (740°42' 49.1" N., 95'03' 33.7"W.)

14) Meretta Lake

Thanks to D. Lean bulk sarnples were collected for: 15) Amitu k Lake

July 12

TraveIled fiom ResoIute to Aiert. B) ALERT, N. ELLESMERE ISLAND

Water and sediment were sampled at the foilowinç sites and phytoplankton and zoopkinkton were coIlectea f?om most of them as well: July 13,14 and 15

The water and sediment were sampled at the followinç sites: Upper Dumbell Lake (UDL) 16) Moat (82'29' 6.6" N., 62'28' 28.1" W.) 17) Hole 1 (82'29' 4.1" N.,62O28' 58.0" W.) 18) Hole 2 (82'29' 4.7" N., 62'29' 7.0" W.) 19) Hole 3 (82'29' 4.0" N., 62'29' 6.5" W.) 20) Hole 4 (82'29' 3 -7"N., 62'29' 6.5" W.) 2 1) Hole 5 (82'29' S. 1" N., 62'29' 3 1.1" W.) 22) Hole 6 (82'29' 1 1.5"N., 62'30' 1.6" W.) 23) Hole 7 (S2'29' 10.0" N., 62'30' 55.2" W.) July 16

The water and sediment were sampled at the foUowing sites: 24) Kirk Lake Ice Edge (82 27.872' N., 62 49.650' W.) 6 cores were taken using the ice edge and the boat for platforms 25) Kirk Stream

26) "Loon Pond" (82'27.463' N., 62'55.909' W.)

July 17

The water and sediment were sampled at the following sites: Lower Dumbell Lake (LDL) 27) Moat (82'29' 19.8 N., 62'34' 49.5"W.) 28) Hole 1 (82'29' 15.3"N., 62'35' 58.4" W.) 29) Hole 2 (82'29' 19.6" N., 62'35' 38.5"W.) 30) Hole 3 (approximately 1 m. from Hole 2)

July 18

Fog and snow made it impossible to leave the base. Samples and equipment were reorganized, some material was processed.

July 19.20 and 21 The water and sediment were sampled at the foiiowing sites: 3 1) Pond A- 1 (82'29' 07.0" N., 62'24' 3 6.1 " W.) 32) Pond A-2 (82'29' 09.1" N., 62'25' 18.5" W.) 33) Pond A-3 (82'29' 07.1" N., 62'26' 08.7" W.) 34) Pond A-4 (82'29' 34.9" N., 62'25.1" 16.7" W.) 35) Pond A-5 (SZ02S' 20.1" N., 62'32' 23.9" W.)

36) Self Pond

37) Upper Dumbeil Lake Stream (82O28' 46.9" N., 62'28' 33.7" W.)

38) "Runway Pond" adjacent to airstrip.

Thanks to G. Momsson of CWS and N. Davidson, bulk sarnples were obtained for: 39) White Pond 40) Moss Pond

July 22

Al1 sarnples and equipment were packed for shipment. JuIy 23

Lefi Alert at approximately 9 AM.

41) Air FiIter Samples

The air filtering was done at Upper Dumbeil Lake on a trial bais, varying both length of tirne penod during which each filter was exposed and also the filter pore size. The pump was set up on July 13 at 4 prn and removed on July 21, 1992 at 1255 pm. A total of six dserent time period/filter pore size combinations were tried. A Gauss pump and Swin Lok filter hoIder provided by Dr. Hopper were used. Power was obtained using a long extension cord fiom the pumphouse.

42) Vegetation Sarnples

Vegetation on Cornwallis and at Alert was generaIly sparse? with ocassional oasis usually associated w-th more favourable microclimates. Vegetation could ody be considered to be abundant in those highly favourable sites which contained nutrient sources, such as south-facing slopes in drainage areas below buildings, or in association with lemming burrows (eg. near PCSP faciIity at Resolute). Small sarnples of vegetation, particularly those with "cüshion" growth foms, were collected at a number of sites. Genera sampled incIuded: Saxifiaqa. Alopecuris, Festuca, Draba, Minuartia; with specimens of a number of other genera being taken in very srnaII quantities. '

Some of this material has been provided to K. Reimer at Royal Roads for organic analysis, some to J. Poland at Queen's for metal analysis, and some has been retained for study of passive collection. Care was taken to collect only were the vegetation was relatively abundant, and to take modest amounts. Lirnited coIlectinç was done for purposes of identification and these specimens will be housed in the Fowler Herbarium at Queen's.

5. Overview

A large number of sites were investigated during the field season. Sampling was extremely successfiil, despite adverse weather conditions, thmks to transportation provided by PCSP at Resolute and by DND and AES at Alert. The quality and quantity of sarnples obtained is high.

6. Acknowledgements

The support of Atmospheric Environment Service through this contract, of the AESMserc Subvention Programme, of Polar Continental Shelf Project, of Emof the Department of National Defence, CFS Alert, of Royal Roads Military College Environmentai Sciences Group, of DIAND, of Environment Canada, and of Queen's University, is gratefully acknowledged. Many individuals, both within the agencies named above, and elsewhere, provided extremely helpful adviq and we thank them. APPENDlX 4.3 SELF POND, ALERT CORE JPS-92-SP-CORE 3 PUSH CORE 315 Self Pond, Alert, N.W.T. Sample - SP Core 3 (Push Core) Page 1 Particle type (Counts) SPCBK SPNBK Psph Spheroid chtot cmamop cmanop cmamnop cmmix Subtot Sample No Depth (cm,) SP-907D 0-0.5 56 4 O O 3 O O O O 63 SP-908C 0.5-1 .O 79 3 3 O O O O O O O 112 SP-909A 1,O-1.5 86 43 1 , O 130 SP-91OB 1.5-2.0 105 13 O O 118 SP-911B 2.0-2.5 144 84 O O 6 36 270 SP-912C 2.5-3.0 O O O O O O O O O SP-912B 2.5-3.0 51 20 O 4 20 29 124 SP-913B 3.0-3.5 26 15 O O 12 19 7 2 SP-914D 3.5-4,O 12 15 O O 15 5 47 SP-9158 4.0-4.5 7 13 2 7 2 11 42 SP-9256 9.5-1 0.0 8 8 7 9 37 Total in Core 574 248 1 O 9 67 2 O 109 1015

Self Pond Counts (adj) Sample No Depth (cm, SPCBK SPNBK Psph Spheroid chtot cmamop cmanop cmamnop cmmix Subtot SP-907D 0-0.5 46,66667 3.333333 O O 2.5 O O O O 52,5 SP-908C 0.5-1 .O SP-909A 1.O-1.5 SP-91OB 1,5-2.0 SP-911B 2,O-2,5 SP-912C 2.5-3.0 SP-9128 2.5-3.0 SP-913B 3.0-3,5 SP-914D 3.5-4,0 SP-915B 4.0-4.5 SP-9256 9.5-10.0 Total in Core APPENDIX 4.3 SELF POND, ALERT CORE JPS-92-SP-CORE 3 PUSH COR€ Page 2 Self% Rounded to 2 d.pt. Depth (cm. SPCBK Psph Spheroid chtot cmamop cmanop crnamnop cmmix sum 0.5 5.27 O O 0.34 O O O O 5.95 1 8.07 O O O O O O O 11.43 1.5 10.76 0.11 O O O O O O 16.25 2 9.87 O O O O O O O 11.1 2.5 13.45 O O O 0.56 O O 3.36 25.22 3 5.72 O O 0,45 2.24 O O 3.25 13,9 3.5 2.47 O O O 1.12 O O 1,79 6,84 4 1,O1 O O O 1.23 O O 0,45 3.92 4.5 0.45 O O 0.1 1 0.45 0.1 1 O 0.67 2.69 10 0,67 O O O 0.56 O O 0.78 2.68

Subtot 57.74 0.1 1 O 0.9 6.16 0.11 O 10,3 99,98 APPENDIX 4.4 KlRK LAKE ALERT CORE JSP-92-KL-5 Kirk counts (Adj.) Rounded to lntegers SPCBK SPN8K Psph Diesel-type chtot SUM KL-1 B 6 O O O 2 8 KL-2A 8 O O O 6 14 KL-3C 6 O O 1 5 12 KL-4D 10 O O 3 3 16 KL-5D 6 O O O 2 8 KL-GA 4 O O O 2 6 KL-7B 1 2 O O O 3 KL-8B 3 2 O O O 5 KL-SB 1 O O O 1 2 KL-4 OC 1 O O O 1 2 KL-11D O O O O O O KL-13B O O O O O O KL-14D O O O O O O KL-15A O O O O O O 46 4 O 4 22 76

APPENDIX 4.4 KlRK LAKE ALERT CORE JSP-92-KL-5 Kirk Oh (Values) Rounded to lntegers SPCBK SPNBK Psph Diesel-type chtot SUM KL-1 B 8 O O O 3 Il KL-2A II O O O 8 18 KL-3C 8 O O 1 7 16 KL4D 13 O O 4 4 21 KL-5D 8 O O O 3 11 KL-GA 5 O O O 3 8 K L-7 B 1 3 O O O 4 KL-8B 4 3 O O O 7 KL-98 1 O O O 1 3 KL-1OC 1 O O O 1 3 KL-11 D O O O O O O KL-138 O O O O O O KL-140 O O O O O O KL-15A O O O O O O su btot 61 5 O 5 29 1O0 APPENDIX 4.5 TABLE 4.5.1 LOWER DUMBELL LAKE CORE JPS-92-LDL-H3C2 (MW COUNTS)

Depth (cm) SPCBK (equiv) charcoal Subtotal 0-0.5 77 6 83 0-5-1.O 1.0-1 -5 1- 5-2.0 2-0-2.5 2-5-3.0 3-0-3.5 3.5-4.0 4-0-4.5 4.5-5.0 5.0-5.5 5.5-6.0 9.5-1 0 Subtotal TABLE4.5.2.LOWER DUMBELL LAKE CO RE J PS-92-LDL-H3C2 (RELATIVE ABUNDANCE %) Depth (cm) SPCBK (equiv) charcoal Subtotal 0-0.5 11 .O6321 839 0.862069 11.92529 0.5-1 .O 49.2816092 3.87931 53.16092 1.0-1 -5 27.44252874 3.01 7241 30.45977 1-5-2.0 4.166666667 O 4.166667 2.0-2.5 0.287356322 O 0.287356 2.5-3.0 O O O 3.0-3.5 O O O 3.5-4.0 O O O 4.0-4.5 O O O 4.5-5.0 O O O 5.0-5.5 O O O 5.5-6.0 O O O 9.5-1 0 O O O Subtotal 92.241 37931 7.758621 1O0

TABLE4.5.3. LOWER DUMBELL LAKE (RELATIVE ABUNDANCE %) CORE JPS-92-LDL-H3C2 Depth (cm) SPCBK (equiv) charcoal Subtotal 0-0.5 11 1 12 0.5-1 .O 49 4 5 3 1.0-1 -5 27 3 3 O 1.5-2.0 4 O 4 2.0-2.5 O O O 2.5-3.0 O O O 3.0-3.5 O O O 3.5-4.0 O O O 4.0-4.5 O O O 4.5-5.0 O O O 5.0-5.5 O O O 5.5-6.0 O O O 9.5-1 0 O O O Subtotal 92 8 100 APPENDIX 4.6 HORSESHOE POND CAPE HERSCHEL CORE 17 BS-78-26 319 Page 1 Table 5 Horseshoe Pond, Cape Herschel, Ellesmere Island, N.W.T.Histogram 100% ( 0,lg. dry sediment Adjusted Values) (Array) Size Count code SPCBK Csph SPNBK Psph chbloc chlath cmamop cmanop cmRN Subtotal class >7 HSPIA7 O O O O O O O O O O class 7 - 6 HSPIA6,5 O O O O O 0.5 O O 0.5 1 class 6 - 5 HSPIA5.5 O O O O 1.6 0.5 O O O 2.1 class 5 - 4 HSPIA4.5 O O O O 4.2 2,l O 0.5 1 7,8 class 4 - 3 HSPIA3.5 O 03 0.5 0.5 4.7 2.1 O O O. 5 8.9 class 3 - 2 HSPlA2.5 O O 0.5 O 5,2 2.6 O 0.5 3.1 12 class 2 - 1 HSPIAI .5 5.8 0.5 2.1 O 0.5 0.5 O O 0.5 9,9 class 4 HSPIAI 1 O 1 O O O O O O 2.1 class >7 HSP2B7 O O O O O O O O O O class 7 - 6 HSP206.5 O O O O O,5 0.5 O O O 1 class 6 - 5 HSP205.5 O O O O O O. 5 O O O O. 5 class 5 - 4 HSP2B4.5 O O O O, 5 O 1 O O O l .5 class 4 - 3 HSP2B3.5 1 O 0.5 O 1.9 0.5 O O O 3,9 class 3 - 2 HSP2B2.5 0.5 O O 1,5 O O O O O 1,9 class 2 - 1 HSP2B1.5 1 O O O O O O O O 1 class 4 HSP2B1 O O O O O O O O O O class >7 HSP3B7 O O O O O 0 O O O O class 7 - 6 HSP3B6.5 O O O O O O O O O O class 6 - 5 HSP3B5.5 O O O O 1.3 0.6 O O O 1,9 class 5 - 4 HSP3B4.5 O O O O 3.2 0.6 O O O 3,8 class 4 - 3 HSP3B3,5 1,3 O O 1,9 0.6 O O 0.6 O 4,4 class 3 - 2 HSP3B2.5 3.2 O O 0.6 0,6 O O O 0.6 5 class 2 - 1 HSP3Bl.5 0.6 O 0.6 0.6 O O O O O 1.9 class 4 HSP3Bl 1,9 O 0.6 O O O O O O 2.5

APPENDIX 5.1 TABLE 5.1 Horseshoe Pond Core 17 (8s-78-26) 210 Pb Dating (Estimated)

SampIe Section Sample Number Depth midpoint Decay corrected to date of voIatilnation Year 2lO-Pb Depth (cm) Deph (cm) Wg) Bqlg) 5O%decay (estimated) 1 0.5 0.12549 0.1 3 0.1 3 1978 2 1.5 0.1 0927 0.1 1 3 2.5 0.08839 O .O9 4 3.5 0.071 11 0 .O7 0.065 1956 0.0325 1934 O .O2 0.01625 1912 Horseshoe Pond Core 17 (6s-78-26)

- Year (210 Pb Depth (cm) estimated - date)

210 Pb concentration in Bqlg APPENDIX 6,1 BELCHER ISLANDS 210-PB DATA Actlvity (210-Pb) Aclivity (gamma (cmplg)) std. error (cmplg)) Approdmate alpha Bqlg 210-Pb Date (CRS 137-Cs Pond 6 (%) (Bqlg) 210Pb 137-Cs 21481 210Pb 137-Cs 21481 madel) peak value 1 3.4 0,439 1991 2 3.6 0.378 0.598 0.961 0.015 0,0203 0.027 0,0016 1987 3 2.7 0.281 1980 4 3.3 0,273 1968 5 63 0,14 1944 6 8.1 0.049 1907 7 7.9 0,019 1865 8 9,7 0,018 1850 9 0.015 1O 0.015 0,017 0.002 0.038 0.0014 0.001 0.002 11 9.9 182V 12 13 14 9-3 15 16 17 18 19 20 2 1 22 23 0,015 0.001 0,027 0.0009 O 0.0012

Actlvity (210-Pb) Actlvity gamma (dpmlg) std-error (dpmlg) Approdmate alpha Bqlg 210-Pb Date (CRS 137-Cs RBP (%) (Bqlg) 210Pb 137Cs 214BI 210Pb 137Cs 21481 model) peak value 1 2.2 2,221 1991 2 1.9 1.559 90.54 62.15 2,98 1.301 0.6 0,191 1988 3 2.0 1,525 1984 4 4 1,195 1977 5 3 1,142 69.07 83.55 2.09 0.826 0.5 0.114 1967 -1 963 6 1.9 0,879 1949 8 4.8 0.182 1911 10 85 0.02 2.43 0.58 131 0,134 0.04 0,078 1888

12 nla 1 0.18 2,06 0.082 0,021 0,094 APPENDIX 6.1 RAISED BEACH POND COUNTS BY SAMPLE AND PARTICLE TYPE COUE JPS-91-RBP 328 DRD I \UV counts SPCBK SPNBK Psph Sphd chtot cmamop cmanop am'rPh+-Opaque crnrnix ~ubtot Adj.values RBP-1A 63 270 O O 49 RBP-2D 24 147 8 13 147 RBP3B 12 3 1 O 18 8 3 RBP-4C 5 5 3 O 105 RBP-SC 3 8 2 8 89 RBP-7 13 9 2 12 124 RBP-SC O O O O 7 RBP-11D O O O O 2 1 RBP-13B 3. -l O 1 35 RBP-15 O O O O 17 subtot 123 47 1 15 52 677 APPENDIX 6.1 CORE JPS-91-RBP Pooled categories for charcoal and combustion totals as Spectra - Le. each sample = 100% (except for rounding discrepancies) RBP count: SPCBK chtot cmoptot sutot RBP-IA 14 Il 15 1O0 RBP-2D 7 46 1 100 RBP-30 8 53 20 1O1 RBP-4C 4 74 19 1O1 RBP-5C 3 78 12 1O0 RBP-7 7 70 17 99 RBP-9C O 100 O 1O0 RBP-1 1D O 95 5 1O0 RBP-13B 7 85 5 99 RBP-15 O 1O0 O 100 cn CV CC)

O m CC) POND 5 COUNTS BY SAMPLE, SlZE CLASS AND PARTICLE TYPE 330 Page 2 chbloc chang chlath chlacy chamor chRN cmlacy class >7 PSI B7 class 7 - 6 P51B6.5 class 6 - 5 PSI B5.5 class 5 - 4 P5184.5 class 4 - 3 P51B3.5 class 3 - 2 P51B2.5 class 2 - 1 PSI BI,5 classcl P51B1 class >7 P52D7 class 7 - 6 P52D6.5 class 6 - 5 P52D5.5 class 5 - 4 P52D4.5 class 4 - 3 P52D3.5 class 3 - 2 P5202.5 class 2 - 1 P52D1.5 class 4 P52D1 class >7 P53A7 class 7 - 6 P53A6,5 class 6 - 5 P53A5.5 class 5 - 4 P53A4.5 class 4 - 3 P53A3.5 class 3 - 2 P53A2.5 class 2 - 1 P53A1.5 class 4 P53Al class >7 P54D7 class 7 - 6 P54D6.5 class 6 - 5 P54D5.5 class 5 - 4 P54D4.5 class 4 - 3 P54D3.5 class 3 - 2 P54D2.5 class 2 - 1 P54Dl.5 POND 5 COUNTS BY SAMPLE, SlZE CLASS AND PARTICLE TYPE Page 3 cmmix cmamop cmR crnanop cmRN cmamRN Subtot class >7 PSI B7 class 7 - 6 P5166.5 class 6 - 5 P51B5.5 class 5 - 4 P51B4.5 class 4 - 3 P51B3.5 class 3 - 2 P51B2.5 class2 - 1 P51B1.5 classcl P51B1 class >7 P52D7 class 7 - 6 P52D6.5 class 6 - 5 P52D5,5 class 5 - 4 P52D4.5 class 4 - 3 P52D3.5 class 3 - 2 P52D2,5 class 2 - 1 P52DI.5 class <1 P52D1 class >7 P53A7 class 7 - 6 P53A6,5 class 6 - 5 P53A5.5 class 5 - 4 P53A4,5 class 4 - 3 P53A3.5 class 3 - 2 P53A2,5 class 2 - i P53A-i .5 class 4 P53Al class >7 P54D7 class 7 - 6 P54D6.5 class 6 - 5 P54D5.5 class 5 - 4 P54D4.5 class 4 - 3 P54D3.5 class 3 - 2 P54D2.5 class 2 - 1 P54D1.5

POND 5 COUNTS BY SAMPLE, SlZE CLASS AND PARTICLE TYPE Page 5 333 Sample Cc chbloc chang chlath chlacy chamor chRN cmlacy class 4 P54Dl class >7 P55A7 class 7 - 6 P55A6.5 class 6 - 5 P55A5.5 class 5 - 4 P55A4.5 class 4 - 3 P55A3.5 class 3 - 2 P55A2,5 class 2 - 1 P55A1.5 class cl P55A1 class >7 P56A7 class 7 - 6 P56A6.5 class 6 - 5 P56A5.5 class 5 - 4 P56A4,5 class 4 - 3 P56A3,5 class 3 - 2 P56A2,5 class 2 - 1 P56A1.5 class cl P56A1 class >7 P57B7 class 7 - 6 P57B6.5 class 6 - 5 P57B5.5 class 5 - 4 P57B4.5 class 4 - 3 P57B3.5 class 3 - 2 P57B2.5 class 2 - 1 P57B1.5 class 4 P57B1 class >7 P58B7 class 7 - 6 P5866.5 class 6 - 5 P58B5.5 class 5 - 4 P58B4.5 class 4 - 3 P58B3.5 class 3 - 2 P5882.5 class 2 - 1 P58Bl.5 class <1 P58B1 POND 5 COUNTS BY SAMPLE, SlZE CLASS AND PARTICLE TYPE Page 6 Sample Cc cmmix cmamop cmR cmanop cmRN cmamRN Subtot class <1 P54D1 11 class >7 P55A7 2 20 class 7 - 6 P55A6.5 35 class 6 - 5 P55A5.5 65 class 5 - 4 P55A4.5 113 class 4 - 3 P55A3.5 9 7 class 3 - 2 P55A2.5 113 class 2 - 1 P55AI .5 1 3 2 class cl P55A1 1 20 class >7 P56A7 11 class 7 - 6 P56A6.5 13 class 6 - 5 P56A5.5 25 class 5 - 4 P56A4.5 5 1 class 4 - 3 P56A3.5 5 7 class 3 - 2 P56A2.5 6 1 class 2 - 1 P56A1,5 18 class cl P56A1 4 class >7 P57B7 1 class 7 - 6 P57B6,5 5 class 6 - 5 P57B5.5 1 20 class 5 - 4 P57B4,5 66 class 4 - 3 P57B3.5 80 class 3 - 2 P57B2,5 64 class 2 - 1 P5ï'Bl,5 29 class cl P57B1 9 class >7 P58B7 3 class 7 - 6 P58B6,5 14 class 6 - 5 P5885,5 35 class 5 - 4 P58B4.5 5 1 class 4 - 3 P58B3.5 76 class 3 - 2 P58B2.5 43 class 2 - 1 P58Bl.5 10 class cl P58B1 1 APPENDIX 6.1 Dry Pond, Belcher Islands, Nunavut Particle Counts by Type - Dry Pond CORE JPS-91-DP

Particle type SCP- SP- BK NBK NSCPBK charcoal Subtotal SampIe r Depth (cm.) DP-1 27 6 8 41 DP-2A 28 15 18 10 71 D P-4 28 21 19 IO 78 DP-5 28 18 27 14 87 D P-7 II 2 17 14 44 DP-9 5 2 1 1 9 DP-11 O O 1 3 4 DP-13 1 O O 2 3 DP-15A O 2 1 3 6 DP-17A O O 4 O 4 Total in Core 128 66 88 65 347

Percentage Relative Abundance - Dry Pond CORE JPS-91-DP Control 98-2-6 O O Dry Pond SPCBK SPNBK NSPCBK chtot subtot DP-1 21 9 O 12 12 DP-2A 22 23 20 15 20 DP-4 22 32 22 15 22 DP-5 22 27 31 22 25 DP-7 9 3 19 22 13 DP-9 4 3 1 2 3 DP-11 O O 1 5 1 DP-13 1 O O 3 1 DP-15A O 3 1 5 2 DP-17A O O 5 O 1 Total in Core 1O0 1O0 1O0 1O0 i 00 336 APPENDIX 6.2 DRY POND, BELCHER ISLANDS, HUDSON BAY, NUNAWT

Dry Pond

Combustion particle types

In the samples from the Dry Pond core, the following combustion particle types were recorded:

1. spheroidal carbonaceous black type (SPCBK) 2. charcoal total (chtot) 3. splieroidal type (SPNBK) 4. nonsplieroidal combustion black

All of tliese particles were included in tlie counts of total combustion particles and in the subsequent calculation of relative abundance. The distribution of al1 types in tlie Dry Pond samples was interesting as a more even allocation by type was observed.. Relative abundances ranged from just under 20% for total charcoaI and splieroidal non-black types; to 24% for nonsplieroidal combustion black (equivaleiit to combustion arnorplious opaque, cmamop type) and 38% for splieroidal carbonaceous black particles (SPCBK type).

Total combustion particle type distributions are presented as histograms. Individual categories of particles are then isolated from them and presented as profiles of tlie contribution of that type in terms of relative abundance with deptli.

Distribution with dcpth

Total combustion particle occurrence Tlie distribution of total combustion particles witli deptti in Dry Pond indicates that approximately 90% of the total combustion particle load in the Dry Pond samples is found in the top 7 cm of the core. The surface sample accounts for approximately 16% and a sliglit increase is obsewed below. witli a masimum of 23% for samples anatysed at a depth of 4 cm Tliere is a sliglit decrease by 5 cm to 2 1%, tlien at 7 cm a drop to 13% is seen. At 9 cm tlie relative abundance of total combustion particles observed is approximately 3%. Relative abundance continues to decline slowly witli deptli, escept for a slight increase (to approximately 2%), obsewed at 15 cm The relative abundance then drops to 1 % at the bottom of the core.

Splieroidal carbonaceous black particle type (SPCBK) Witli the exception of an occurrence of the maximum at the top of the core, tlie profile of relative abundance of SPCBK type particles in the Dry Pond core shows a gradua1 decline witli depth from over 1 1 % at O to 1 cm to >2% at 8 cm . SPCBK type particles are not detected at 1 1 cm, but do appear at > 1% in the sample at 13 cm, witli no further observed occurrence below tliis.

Charcoal type (total) (chtot) The relative abundance ofcharcoal particles of al1 types, as a percentage of total combustion particles enurnerated in the Dry Pond samples, with sediment depth. The highest relative abundance of charcoal particles in any Dry Pond sarnple (> 4%), occurs at 7 cm depth. From 7 cm to the top of the core, levels range from 3 to 3.5% appmximately. Below the rna,~imurnat 7 cm there is a marked decrease at 9 cm, to approximately 0.25%. Levels then increase somewhat with depth, although no values for relative abundance from samples deeper in the core are > 1%.

Non-spheroidal black corn bustion particles (combustion opaque, or cmop) type This broad category represents a supergroup composed of al1 types of cLcombustion opaque" particles, including amorphous, angular and rounded types, found in the Dry Pond sarnples. The relative abundance of this group in relation to the total combustion particle inventory for al1 types shows that these particles are slightly more abundant with depth. At 5 cm tliere are more (6.5%), than at the surface (- 5.8%). At 7 cm, relative abundance drops to 5%, and at 9 cm, to c 0.5%. Although there appears to be a slight increase at tlie bottom of the core, IeveIs below 9 cm are less tlian 1% in al1 samples analysed.

FIGURE - . Dry Pond ,Belcher Islands, Nunavut. Histograrn of the distribution of combustion particles observed in the Dry Pond sarnples by particle type, showing relative abundance as percentage oftotal combustion particles enurnerated.

SPCBK - spheroidal, carbonaceous, black type Csph - cenosphere type SPNBK - spheroidal, non-black type Psph - pleurosphere type Spheroid - not clearly member of previous spheroidal types charcoal- total charcoal of al1 types

SPCBK SPNBK PSP NSPCBK charcoal Combustion particle type