DOCSLIB.ORG

Thesis Fire History and Serotiny in the Rocky

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Thesis Fire History and Serotiny in the Rocky THESIS FIRE HISTORY AND SEROTINY IN THE ROCKY MOUNTAINS OF COLORADO Submitted by Carissa F. Aoki Department of Forest, Rangeland and Watershed Stewardship In partial fulfillment of the requirements For the Degree of Master of Science Colorado State University Fort Collins, Colorado Spring 2010 COLORADO STATE UNIVERSITY April 5, 2010 WE HEREBY RECOMMEND THAT THE THESIS PREPARED UNDER OUR SUPERVISION BY CARISSA F. AOKI ENTITLED FIRE HISTORY AND SEROTINY IN THE ROCKY MOUNTAINS OF COLORADO BE ACCEPTED AS FULFILLING IN PART REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE. Committee on Graduate Work ________________________________________ Melinda Laituri ________________________________________ Philip Cafaro ________________________________________ Advisor: William Romme ________________________________________ Co-Advisor: Peter Brown ________________________________________ Department Head: Michael Manfredo ii ABSTRACT OF THESIS FIRE HISTORY AND SEROTINY IN THE ROCKY MOUNTAINS OF COLORADO Fire is a natural part of forested ecosystems in Colorado, playing an essential role in regenerating and maintaining forests. I studied two aspects of fire: historical fire regime in mixed-conifer forests, and serotiny in lodgepole pine. I. During the 1990s and early 2000s, fire management in the western United States was often based on lessons learned from fire regime studies in ponderosa pine ecosystems in the Southwestern states. As managers sought to apply these policies to an ever-broader range of forest types, it became clear that different forest types were characterized by different fire regimes and thus required further research as well as new management strategies. Mixed-conifer forests have been particularly hard to quantify in terms of their historical fire regimes. My study aimed to understand the historical range of variability (HRV) in a mesic mixed-conifer forest in southwestern Colorado. Banded Peak Ranch, located in the San Juan Mountains of Colorado, provided a unique setting in which to study the historical fire regime of this forest type in the southern Rocky Mountains. I used a combination of stand age structure, species composition, and fire scar data, collected at two different spatial scales on 40 plots, in both logged and iii unlogged stands. At both scales, I found a combination of mixed- and high-severity fire regimes. The spatial distribution of fire severity appears to have been patchy, with mixed- and high-severity stands lying in close proximity to one another. Species composition and age structure varied widely among both the high- and mixed- severity stands, suggesting that a variety of future disturbance regime trajectories might be expected. II. Regeneration in Rocky Mountain lodgepole pine (Pinus contorta var. latifolia) is characterized by two methods of reproduction: serotinous cones, which open and release their seeds only under heat from fire; and non-serotinous cones, which open and release their seeds with cone maturity. Stands with a high proportion of serotinous cones can thus regenerate strongly following stand-replacing fire. I used data from across Rocky Mountain National Park (ROMO) to quantify the distribution of serotiny on the landscape and to try to understand the key abiotic variables controlling serotiny. I found that serotiny varied from 0-97% per stand, with an average across the landscape of 58%. Because my data did not correlate strongly with any single variable, I used regression tree analysis to explore the combined effects of abiotic variables on serotiny. Elevation, aspect, and topographic convergence index (a measure of local moisture) were the key variables in the resulting regression tree, and higher serotiny was correlated with the range of each variable that is more conducive to fire—lower, more west-facing, drier. Previous research has shown that serotiny is affected by stand-replacing fire, but not by low-severity fire. In an environment such as the lodgepole pine forests of ROMO, where stand-replacing fire is the predominant fire regime, serotiny is highly related to the environmental variables that generally contribute to fire occurrence. iv III. Serotinous cones remain on living trees for many years, holding within them the canopy seed bank for regeneration after fire. After large-scale mortality caused by mountain pine beetle (Dendroctonus ponderosae), however, the seeds in serotinous cones may remain on the dead trees for a number of years. I tested seeds from living and beetle-killed serotinous stands to determine whether they remain viable after tree death, and whether germination rates were affected by cone age. There was no significant difference between germination success rates from the living stand vs. the dead stand. While there was a significant relationship between cone age and germination success, cones that were 21-25 yrs still had >30% germination rates. I conclude that post-beetle regeneration likely will not be limited by viable seed availability in stands with serotinous cone-bearing trees. Carissa F. Aoki Department of Forest, Rangeland and Watershed Stewardship Colorado State University Fort Collins, CO 80523 Spring 2010 v ACKNOWLEDGMENTS First and foremost I would like to thank my advisors, Peter Brown and Bill Romme, for the teaching, guidance, and project opportunities they provided me during my time at Colorado State. I would also like to thank the other members of my committee, Melinda Laituri and Phil Cafaro. I thank the owners and managers of Banded Peak, Catspaw, and Navajo Headwaters Ranches for their support and participation in the fire history study. In addition to providing terrific field support, they completely changed my perspective about the nature of private land ownership, and the role of private landowners in 21st century conservation efforts. For the project at Rocky Mountain National Park, I thank Judy Visty and the many other park staff who made our project possible and enjoyable. For their help in the field and lab, I thank Brandon Corcoran, Jonas Feinstein, Luke Griscom, Jared Lyons, Jed Meunier, Greg Pappas, Katie Shields, and Lisa Slepetski. Monique Rocca, Matt Diskin, and Kellen Nelson were great colleagues on the Rocky Mountain National Park project. They and their other lab members graciously allowed me to be a guest at their meetings, from which I gained invaluable assistance and feedback. Jason Sibold generously allowed me to use his serotiny data, and I thank David Coblentz for his assistance with topographic data analysis. This work was funded by Banded Peak Ranch, a McIntyre-Stennis grant to Colorado State University and a National Science Foundation Graduate Research Fellowship. Finally I thank Lin Murphy, whose support and good cheer makes my work possible. vi Table of Contents Foreword ................................................................................................................. 1 Chapter 1: Fire Regime of a Mixed-Conifer Forest in Southwestern Colorado ... 3 Introduction ......................................................................................................... 3 Methods ............................................................................................................... 7 Study area ........................................................................................................ 7 Sampling methods ........................................................................................... 9 Fire severity determination ............................................................................ 13 Results ............................................................................................................... 15 Fire scar data .................................................................................................. 15 Species composition, aspen establishment dates, general age structure ........ 19 Fire severity classification ............................................................................. 23 Fire severity results ........................................................................................ 24 Discussion and Management Recommendations .............................................. 25 Fire regime ..................................................................................................... 26 Historical range of variability (HRV) ............................................................ 29 Conclusion ......................................................................................................... 32 Appendix A. Detailed forest structure and species composition data ................ 1 Appendix B: Fire severity map ........................................................................ 36 Chapter 2: Lodgepole pine serotiny in Rocky Mountain National Park ............. 46 Introduction ....................................................................................................... 46 Methods ............................................................................................................. 47 Study Location ............................................................................................... 47 Methods ............................................................................................................. 48 Field Sampling ............................................................................................... 48 Additional topographic variables ................................................................... 51 Statistical Analysis .......................................................................................
Load more

Recommended publications
  • Fire Structures Pine Serotiny at Different Scales
    American Journal of Botany 100(12): 2349–2356. 2013. F IRE STRUCTURES PINE SEROTINY AT DIFFERENT SCALES 1 A NA H ERNÁNDEZ-SERRANO 2 , M IGUEL V ERDÚ 2 , S ANTIAGO C. GONZÁLEZ-MARTÍNEZ 3 , AND J ULI G. PAUSAS 2,4 2 CIDE-CSIC, Ctra. Nàquera Km. 4.5 (IVIA campus) 46113 Montcada, Valencia, Spain; and 3 CIFOR-INIA, Ctra. A Coruña Km 7.5 28040 Madrid, Spain • Premise of the study: Serotiny (delayed seed release with the consequent accumulation of a canopy seedbank) confers fi tness benefi ts in environments with crown-fi re regimes. Thus, we predicted that serotiny level should be higher in populations recur- rently subjected to crown-fi res than in populations where crown-fi res are rare. In addition, under a high frequency of fi res, space and resources are recurrently available, permitting recruitment around each mother to follow the seed rain shadow. Thus, we also predicted spatial aggregation of serotiny within populations. • Methods: We compared serotiny, considering both the proportion and the age of serotinous cones, in populations living in contrasting fi re regimes for two iconic Mediterranean pine species (Pinus halepensis , P. pinaster ). We framed our results by quantitatively comparing the strength of the fi re–serotiny relationship with previous studies worldwide. • Key results: For the two species, populations living under high crown-fi re recurrence regimes had a higher serotiny level than those populations where the recurrence of crown-fi res was low. For P. halepensis (the species with higher serotiny), popula- tions in high fi re recurrence regimes had higher fi ne-scale spatial aggregation of serotiny than those inhabiting low fi re recur- rence systems.
    [Show full text]
  • Influence of Fire Interval and Serotiny on Postfire Lodgepole Pine Density in Yellowstone National Park
    Utah State University DigitalCommons@USU Quinney Natural Resources Research Library, The Bark Beetles, Fuels, and Fire Bibliography S.J. and Jessie E. 2003 Influence of Fire Interval and Serotiny on Postfire Lodgepole Pine Density in Yellowstone National Park Tania Schoennagel Monica G. Turner William H. Romme Follow this and additional works at: https://digitalcommons.usu.edu/barkbeetles Part of the Ecology and Evolutionary Biology Commons, Entomology Commons, Forest Biology Commons, Forest Management Commons, and the Wood Science and Pulp, Paper Technology Commons Recommended Citation Schoennagel, T., Turner, M. and Romme, W. (2003). Influence of fire interval and serotiny on postfire lodgepole pine density in Yellowstone National Park. Ecology, 84(11): 2967—2978. This Article is brought to you for free and open access by the Quinney Natural Resources Research Library, S.J. and Jessie E. at DigitalCommons@USU. It has been accepted for inclusion in The Bark Beetles, Fuels, and Fire Bibliography by an authorized administrator of DigitalCommons@USU. For more information, please contact [email protected]. Ecology, 84(11), 2003, pp. 2967±2978 q 2003 by the Ecological Society of America THE INFLUENCE OF FIRE INTERVAL AND SEROTINY ON POSTFIRE LODGEPOLE PINE DENSITY IN YELLOWSTONE NATIONAL PARK TANIA SCHOENNAGEL,1,3 MONICA G. TURNER,1 AND WILLIAM H. ROMME2 1Department of Zoology, University of Wisconsin, Madison, Wisconsin 53706 USA 2Department of Forest Sciences, Colorado State University, Fort Collins, Colorado 80523 USA Abstract. The time interval between stand-replacing ®res can in¯uence patterns of initial post®re succession if the abundance of post®re propagules varies with pre®re stand age.
    [Show full text]
  • Evolutionary History of Floral Key Innovations in Angiosperms Elisabeth Reyes
    Evolutionary history of floral key innovations in angiosperms Elisabeth Reyes To cite this version: Elisabeth Reyes. Evolutionary history of floral key innovations in angiosperms. Botanics. Université Paris Saclay (COmUE), 2016. English. NNT : 2016SACLS489. tel-01443353 HAL Id: tel-01443353 https://tel.archives-ouvertes.fr/tel-01443353 Submitted on 23 Jan 2017 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. NNT : 2016SACLS489 THESE DE DOCTORAT DE L’UNIVERSITE PARIS-SACLAY, préparée à l’Université Paris-Sud ÉCOLE DOCTORALE N° 567 Sciences du Végétal : du Gène à l’Ecosystème Spécialité de Doctorat : Biologie Par Mme Elisabeth Reyes Evolutionary history of floral key innovations in angiosperms Thèse présentée et soutenue à Orsay, le 13 décembre 2016 : Composition du Jury : M. Ronse de Craene, Louis Directeur de recherche aux Jardins Rapporteur Botaniques Royaux d’Édimbourg M. Forest, Félix Directeur de recherche aux Jardins Rapporteur Botaniques Royaux de Kew Mme. Damerval, Catherine Directrice de recherche au Moulon Président du jury M. Lowry, Porter Curateur en chef aux Jardins Examinateur Botaniques du Missouri M. Haevermans, Thomas Maître de conférences au MNHN Examinateur Mme. Nadot, Sophie Professeur à l’Université Paris-Sud Directeur de thèse M.
    [Show full text]
  • In the Late Cretaceous and Their Increasing Dominance in the Anthropocene
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by CONICET Digital Received: 31 May 2018 | Revised: 21 July 2018 | Accepted: 4 August 2018 DOI: 10.1002/ece3.4499 REVIEW Insights on the persistence of pines (Pinus species) in the Late Cretaceous and their increasing dominance in the Anthropocene Surendra P. Singh1 | Inderjit2 | Jamuna S. Singh3 | Sudipto Majumdar2 | Jaime Moyano4 | Martin A. Nuñez4 | David M. Richardson5 1Central Himalayan Environment Association (CHEA), Nainital, India Abstract 2Department of Environmental Although gymnosperms were nearly swept away by the rise of the angiosperms in Studies, Centre for Environmental the Late Cretaceous, conifers, and pines (Pinus species) in particular, survived and Management of Degraded Ecosystems (CEMDE), University of Delhi, Delhi, India regained their dominance in some habitats. Diversification of pines into fire- avoiding 3Department of Botany, Banaras Hindu (subgenus Haploxylon) and fire- adapted (subgenus Diploxylon) species occurred in re- University, Varanasi, India sponse to abiotic and biotic factors in the Late Cretaceous such as competition with 4Grupo de Ecologia de Invasiones, INIBIOMA, CONICET/ emerging angiosperms and changing fire regimes. Adaptations/traits that evolved in Universidad Nacional del Comahue, response to angiosperm- fuelled fire regimes and stressful environments in the Late Bariloche, Argentina Cretaceous were key to pine success and are also contributing to a new “pine rise” in 5Department of Botany and Zoology, Centre for Invasion Biology, Stellenbosch University, some areas in the Anthropocene. Human- mediated activities exert both positive and Matieland, South Africa negative impacts of range size and expansion and invasions of pines. Large- scale af- Correspondence forestation with pines, human- mediated changes to fire regimes, and other ecosys- Inderjit, Department of Environmental tem processes are other contributing factors.
    [Show full text]
  • Spatial Patterns of Cone Serotiny in Pinus Banksiana in Relation to Fire Disturbance
    Forest Ecology and Management 189 (2004) 133–141 Spatial patterns of cone serotiny in Pinus banksiana in relation to fire disturbance Volker C. Radeloffa,*, David J. Mladenoffa, Raymond P. Guriesa, Mark S. Boyceb aDepartment of Forest Ecology and Management, 1630 Linden Dr., University of Wisconsin-Madison, Madison, WI 53703-1598, USA bDepartment of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, USA Received 12 January 2003; received in revised form 3 February 2003; accepted 24 July 2003 Abstract Fire disturbance effects on tree species distribution and landscape pattern have been widely studied. However, the effects of differences among fire regimes on the spatial pattern of genetic variability within a tree species have received less attention. The objectives of this study were to examine (a) whether the marked gradient in serotiny in Pinus banksiana along its southern range limit is related to differences in fire regimes and (b) at what scale serotiny varies most strongly in P. banksiana in the US Midwest. P. banksiana in the 450,000 ha Pine Barrens area in northwestern Wisconsin, USA showed a marked broad scale pattern in serotiny. The percentage of serotinous trees was highest in the northeast (mean 83%, S.D. 13.5) and lowest in the southwest (mean 9%, S.D. 3.7). Historic fire regimes were inferred from pre-European settlement (mid-1800s) vegetation data. Serotiny was highest in pine forests that exhibited stand-replacing fires, and lowest in savannas where more frequent but less intense ground fires occurred. The data presented in this study suggest possible spatial control of genetic variability within a tree species by an ecological process (disturbance) at the landscape-scale.
    [Show full text]
  • Adepartment of Biology and Environment, Faculty of Natural Sciences, University of Haifa-Oranim, Tivon 36006, Israel
    ISRAEL JOURNAL OF ECOLOGY & EVOLUTION, Vol. 58, 2012, pp. 177–194 10.1560/IJEE.58.2-3.177 FIRE-RELATED TRAITS IN MEDITERRANEAN BASIN PLANTS GIDI NE’EMAN,a,* SIMCHA LEV-YADUN,a AND MARGARITA ARIANOUTSOUb aDepartment of Biology and Environment, Faculty of Natural Sciences, University of Haifa-Oranim, Tivon 36006, Israel. bDepartment of Ecology and Systematics, Faculty of Biology, National and Kapodistrian University of Athens, Athens 15784, Greece. ABSTRACT Fire is a frequent and severe disturbance that affects plants on large scales, es- pecially in Mediterranean-type ecosystems (MTE). Plants have evolved traits that confer resilience to fire and other disturbances, ensuring their persistence in fire-prone systems, but MTE floras differ in fire-related traits and their frequencies. Using available literature, we compare fire-related plant traits and syndromes of the flora of the Mediterranean Basin with those of other MTEs, discuss the differences and their possible causes, and point to knowl- edge gaps. Plants with lignotubers are relatively rare in the Mediterranean, as is serotiny. Many Mediterranean species have physically dormant seeds that are cued to germinate after fire by heat shock, while the effect of smoke on seed germination in the Mediterranean flora is less common than in other MTEs. The geophytes in the MB that flower massively afterfire flowering are opportunistic and not obligate fire-stimulated flowering species. Based on this literature survey, we conclude that differences in current and historic fire re- gimes could account for differences among MTEs in plants’ fire-related traits. Keywords: Plant adaptive traits, flammability, germination, lignotuber, re- sprouting, serotiny, smoke.
    [Show full text]
  • Polar Wildfires and Conifer Serotiny During the Cretaceous Global Hothouse
    Polar wildfires and conifer serotiny during the Cretaceous global hothouse Chris Mays1, David J. Cantrill2, and Joseph J. Bevitt3 1Department of Palaeobiology, Naturhistoriska riksmuseet, Box 50007, S-104 05 Stockholm, Sweden 2Royal Botanic Gardens Victoria, Private Bag 2000, South Yarra, VIC 3141, Australia 3Australian Nuclear Science and Technology Organisation, User Office, B3, New Illawarra Road, Lucas Heights, NSW 2234, Australia ABSTRACT Several highly effective fire-adaptive traits first evolved among modern plants during A CHATHAM ISLAND B (Rekohu) W PACIFIC 44°14’ the mid-Cretaceous, in response to the widespread wildfires promoted by anomalously high E N OCEAN PACIFIC 40° ZEALAND atmospheric oxygen (O2) and extreme temperatures. Serotiny, or long-term canopy seed CHATHAM OCEAN storage, is a fire-adaptive strategy common among plants living in fire-prone areas today, 300km ISLANDS but evidence of this strategy has been lacking from the fossil record. Deposits of abundant S CHATHAM RISE fossil charcoal from sedimentary successions of the Chatham Islands, New Zealand, record 44° B PITT ISLAND 176°E 180° 176°W Tupuangi wildfires in the south polar regions (75°–80°S) during the mid-Cretaceous (ca. 99–90 Ma). 0784 (Rangiaotea) Beach 0799 0815 Newly discovered fossil conifer reproductive structures were consistently associated with Waihere 0807 0811 44°16’S Bay 0812 these charcoal-rich deposits. The morphology and internal anatomy as revealed by neutron 0813 2 km tomography exhibit a range of serotiny-associated characters. Numerous related fossils from 0827 similar, contemporaneous deposits of the Northern Hemisphere suggest that serotiny was a 0814 176°14’W 176°12’ 176°10’ key adaptive strategy during the high-fire world of the Cretaceous.
    [Show full text]
  • Increased Fire Frequency Promotes Stronger Spatial Genetic Structure and Natural Selection at Regional and Local Scales in Pinus Halepensis Mill
    Annals of Botany 119: 1061–1072, 2017 doi:10.1093/aob/mcw286, available online at www.aob.oxfordjournals.org Increased fire frequency promotes stronger spatial genetic structure and natural selection at regional and local scales in Pinus halepensis Mill Katharina B. Budde1,2,*, Santiago C. Gonzalez-Mart ınez1,2, Miguel Navascue´s3, Concetta Burgarella4,†, Elena Mosca5, Zaida Lorenzo1, Mario Zabal-Aguirre1, Giovanni G. Vendramin6, Miguel Verdu7, Juli G. Pausas7 and Myriam Heuertz1,2,* 1INIA Forest Research Centre, Department of Forest Ecology and Genetics, Carretera A Coruna~ km 7Á5, 28040 Madrid, Spain, 2INRA, Universite´ de Bordeaux, UMR 1202 BIOGECO, 33610 Cestas, France, 3INRA, UMR1062 CBGP, 34988 Montferrier- sur-Lez, France, 4INRA, UMR 1334 AGAP, 34060 Montpellier, France, 5Faculty of Science and Technology, Free University of Bolzano, piazza Universita 1, 39100 Bolzano, Italy, 6National Research Council, Institute of Biosciences and Bioresources, Via Madonna del Piano 10, 50019 Sesto Fiorentino (Florence), Italy and 7Centro de Investigaciones sobre Desertificacion (CIDE-CSIC), 46113 Moncada (Valencia), Spain †Present address: IRD, UMR DIADE, BP 64501, Montpellier, France. *For correspondence. E-mail [email protected] or [email protected] Received: 21 October 2016 Returned for revision: 23 November 2016 Editorial decision: 13 December 2016 Published electronically: 4 February 2017 Background and Aims The recurrence of wildfires is predicted to increase due to global climate change, result- ing in severe impacts on biodiversity and ecosystem functioning. Recurrent fires can drive plant adaptation and re- duce genetic diversity; however, the underlying population genetic processes have not been studied in detail. In this study, the neutral and adaptive evolutionary effects of contrasting fire regimes were examined in the keystone tree species Pinus halepensis Mill.
    [Show full text]
  • Serotiny in Southern Hemisphere Conifers
    MURDOCH RESEARCH REPOSITORY This is the author’s final version of the work, as accepted for publication following peer review but without the publisher’s layout or pagination. The definitive version is available at http://dx.doi.org/10.1071/BT13150 Ladd, P.G., Midgley, J.J. and Nield, A.P. (2013) Serotiny in southern hemisphere conifers. Australian Journal of Botany, 61 (6). pp. 486-496. http://researchrepository.murdoch.edu.au/19822/ Copyright: © CSIRO 2013. It is posted here for your personal use. No further distribution is permitted. 1 Serotiny in southern hemisphere conifers 2 3 P.G. Ladd1 , J. J. Midgley2 and A. P. Nield1 4 1School of Veterinary and Life Sciences, Murdoch University, Murdoch, Western 5 Australia 6150 Australia 6 7 2Biological Sciences Department, University of Cape Town, Post Bag Rondebosch, 8 Rondebosch 7701 South Africa 9 10 11 corresponding author – P Ladd, address as above, email [email protected] 12 13 Running heading - Serotiny in southern hemisphere conifers 14 15 Summary text – Protecting seeds in woody containers is a common feature in 16 southern hemisphere woody plants but the cones of southern conifers have been 17 little studied. Cones occur in Callitris – Australia and New Caledonia and 18 Widdringtonia - South Africa and vary greatly in size, whether they stay closed for 19 some years on the plant (serotiny) and how well they protect the seeds from the 20 heat of a fire. Examining the environmental features that are associated with 21 whether cones stay closed or not helps understand the reproductive and ecological 22 behaviour of the trees.
    [Show full text]
  • Aspect of the Evolutionary Biology of the Proteaceae, with Emphasis On
    ASPECTS OF '!HE EVOIDrIONARY BIOI.OOY OF THE PRCYI'EACEAE, WI'IH EMFHASIS ON THE GENUS IEUCADENDRON AND ITS FHYI.OGENY BY JEREMY JOHN MIOOIEY Submitted in part fulfilment of the requirements for the degree IX>CroR OF FHII.OSOPHY in the Department of Botany Faculty of Science University of cape Town March 1987 University of Cape Town The copyright of this thesis vests in the author. No quotation from it or information derived from it is to be published without full acknowledgement of the source. The thesis is to be used for private study or non- commercial research purposes only. Published by the University of Cape Town (UCT) in terms of the non-exclusive license granted to UCT by the author. University of Cape Town We shall not cease from our exploration And the end of all our exploring Will be to arrive where we started And know the place for the first time from: Four Quartets by T. s. Eliot TABIE OF OONl'ENTS Page Preamble 1 Chapter 1. 'Ihe derivation, utility and implications of a divergence index for the fynbos genus I.eucadendron 16 Chapter 2. 'Ihe distribution of the Proteaceae and their associated traits along a fynbos summer moisture stress gradient 45 Chapt;er 3. A biogeographical analysis of the genus I.eucadendron 68 Chapter 4. Factors which detennine, and ecological correlates of, maximum plant height of fynbos Proteaceae species 96 I., . Chapter 5 o '!he evolution of serotiny in the fynbos, with particular reference to the genus I.eucadendron (Proteaceae) 113 Chapter 6. '!he evolution of dioecy, with particular reference to I.eucadendron (Proteaceae) 143 Chapter 7.
    [Show full text]
  • Timing of Fire Relative to Seed Development Controls Availability of Non-Serotinous Aerial Seed Banks
    Biogeosciences Discuss., 9,16705-16751,2012 Biogeosciences www.biogeosciences-discuss.net/9/16705/20 12/ (1::-~ doi:10.5194/bgd-9-16705-2012 ~ Discussions © Author(s) 2012. CC Attribution 3.0 License. This discussion paper isfhas been under review for the journal Biogeosciences (BG) Please refer to the corresponding final paper in BG if available. Timing of fire relative to seed development controls availability of non-serotinous aerial seed banks 1 2 2 3 4 S. T. Michaletz · , E. A. Johnson , W. E. Mell , and D. F. Greene 1 Department of Ecology and Evolutionary Biology, University of Arizona, BioSciences West, Tucson, AZ 85721, USA 2 Department of Biological Sciences and Biogeoscience Institute, University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1 N4, Canada 3Pacific Wildland Fire Sciences Lab, US Forest Service, 400 N. 34th St. Suite 201, Seattle, WA 98103, USA 4 Department of Geography, Planning & Environment, Concordia University, 1455 de Maisonneuve W., H 1255-26 Montreal, QC H3G 1MB, Canada Received: 17 September 2012 -Accepted: 27 October 2012 - Published: 22 November 2012 Correspondence to: S. T. Michaletz ([email protected]) Published by Copernicus Publications on behalf of the European Geosciences Union. 16705 Abstract 0 ~· c (I) The existence of non-serotinous, non-sprouting species in fire regimes where serotiny !Q. 0 confers ~n adaptive advantage is puzzling, particularly when these species recruit ::J poorly from soil seed banks or from burn edges. In this paper, white spruce (Picea ";;? 5 glauca (Moench) Voss) was used to show that the timing of fire relative to seed develop­ ~ ment can control aerial seed bank availability for non-serotinous species.
    [Show full text]
  • Cone Serotiny - Fire Relationships in Lodgepole Pine
    Utah State University DigitalCommons@USU Quinney Natural Resources Research Library, The Bark Beetles, Fuels, and Fire Bibliography S.J. and Jessie E. 1976 Cone Serotiny - Fire Relationships in Lodgepole Pine James E. Lotan Follow this and additional works at: https://digitalcommons.usu.edu/barkbeetles Part of the Ecology and Evolutionary Biology Commons, Entomology Commons, Forest Biology Commons, Forest Management Commons, and the Wood Science and Pulp, Paper Technology Commons Recommended Citation Lotan, J. (1976). Cone serotiny - fire relationships in lodgepole pine. In: Tall Timbers Fire Ecology Conference Proceedings 14, Tall Timbers Research Center, Tallahassee, FL. pp. 267-278 This Contribution to Book is brought to you for free and open access by the Quinney Natural Resources Research Library, S.J. and Jessie E. at DigitalCommons@USU. It has been accepted for inclusion in The Bark Beetles, Fuels, and Fire Bibliography by an authorized administrator of DigitalCommons@USU. For more information, please contact [email protected]. Cone Serotiny­ Fire Relationships in Lodgepole Pine JAMES E. LOTAN 1 INTRODUCTION THROUGHOUT much of its range, lodgepole pine (Pinus contorta Dougl.) produces serotinous cones. Because of a res­ inous bond between the cone scales, serotinous cones do not open at maturity. When subjected to temperatures of 45 to 50 degrees C. (or even higher), the bond breaks, the cones are free to open, and stored seed is released. Wildfires cause cones to open and cones on or near the ground are opened by normal summer soil surface temperatures (Crossley, 1956; Lotan, 1964). Critchfield (1957) classified his Rocky Mountain and Mendocino White Plains subspecies as predominantly serotinous, but with a continuous gradient between Rocky Mountain populations and the open-cone type of the Sierra Nevada.
    [Show full text]