An Examination of the Limnology, Chironomid Biogeography and Paleoecology of Eastern Canadian Arctic Aquatic Ecosystems
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AN EXAMINATION OF THE LIMNOLOGY, CHIRONOMID BIOGEOGRAPHY AND PALEOECOLOGY OF EASTERN CANADIAN ARCTIC AQUATIC ECOSYSTEMS ANDREW S. MEDEIROS A DISSERTATION SUBMITTED TO THE FACULTY OF GRADUATE STUDIES IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY GRADUATE PROGRAM IN BIOLOGY YORK UNIVERSITY TORONTO, ONTARIO AUGUST 2011 Library and Archives Bibliotheque et 1*1 Canada Archives Canada Published Heritage Direction du Branch Patrimoine de I'edition 395 Wellington Street 395, rue Wellington OttawaONK1A0N4 OttawaONK1A0N4 Canada Canada Your file Votre reference ISBN: 978-0-494-80524-4 Our file Notre reference ISBN: 978-0-494-80524-4 NOTICE: AVIS: The author has granted a non L'auteur a accorde une licence non exclusive exclusive license allowing Library and permettant a la Bibliotheque et Archives Archives Canada to reproduce, Canada de reproduire, publier, archiver, publish, archive, preserve, conserve, sauvegarder, conserver, transmettre au public communicate to the public by par telecommunication ou par I'lnternet, preter, telecommunication or on the Internet, distribuer et vendre des theses partout dans le loan, distribute and sell theses monde, a des fins commerciales ou autres, sur worldwide, for commercial or non support microforme, papier, electronique et/ou commercial purposes, in microform, autres formats. paper, electronic and/or any other formats. The author retains copyright L'auteur conserve la propriete du droit d'auteur ownership and moral rights in this et des droits moraux qui protege cette these. Ni thesis. Neither the thesis nor la these ni des extraits substantiels de celle-ci substantial extracts from it may be ne doivent etre imprimes ou autrement printed or otherwise reproduced reproduits sans son autorisation. without the author's permission. In compliance with the Canadian Conformement a la loi canadienne sur la Privacy Act some supporting forms protection de la vie privee, quelques may have been removed from this formulaires secondaires ont ete enleves de thesis. cette these. While these forms may be included Bien que ces formulaires aient inclus dans in the document page count, their la pagination, il n'y aura aucun contenu removal does not represent any loss manquant. of content from the thesis. 1+1 Canada Acknowledgements I am very grateful for the opportunity given to me by my supervisor, Roberto Quinlan, to reach my highest potential. He allowed me to write my own proposal, research questions, and funding applications to be able to conduct this research. I was fortunate to have a supervisor who believed in me and basically allowed me to do anything I wanted. I am also thankful for all of the assistance from Dr. Sarah Finkelstein (University of Toronto), whose input into manuscripts allowed for the successful completion of this dissertation. Likewise, Charlotte Friel and Jane Devlin whom provided additional samples, feedback, and contributions. Dr. Derek Muir, Xiaowa Wang, and colleagues at the NLET water quality laboratory provided all of the analysis of water chemistry, to which was instrumental in the completion of this project. I am also grateful for the assistance and support provided by Mary Ellen Thomas, Jamal Shirley, Dorothy Tootoo and the staff at the Nunavut Research Institute. Likewise, field assistance by Andy Aliyak, Raymond Biastoch, Andrew Dunford, Milissa Elliott, and Christopher Luszczek was appreciated. This project was funded by a NSERC Discovery Grant and NSERC Northern Research Supplement held by RQ, a NSERC Northern Research Internship, NSTP, and additional York University funding for graduate student research. This project had the following approvals: NRI #0501008N, 0300707N, 0301206N, NIRB 08YN023, 07YN035, DFO S-09/10-1011-NU, S-08/09-1002-NU, S-07/08-1015-NU, S-06/07-1023- NU, and a Nunavut Department of Environment Wildlife Research Licence WL000839. iv Contributions Chapter 2: Patterns in the limnology of lakes and ponds across multiple local and regional environmental gradients in the eastern Canadian Arctic. • Manuscript submitted to Inland Waters with authorship: Medeiros, A.S., Biastoch, R.G., Luszczek, C.E., Wang, X.A., Muir, D.G.C. & Quinlan, R. • Study design by ASM and Roberto Quinlan (RQ), limnological data collection by ASM, Raymond G. Biastoch (RGB) and Chris E. Luszczek (CEL), data analysis primarily by ASM, with contributions from RGB (geological data), and CEL (inter regional analysis), manuscript writing by ASM with editorial contributions by RQ. Water chemistry analysis was conducted by Xiaowa A. Wang, and Derek G.C. Muir. Chapter 3: The distribution of the Chironomidae (Insecta: Diptera) along multiple environmental gradients in lakes and ponds of the eastern Canadian Arctic. • Manuscript accepted for publication in the Canadian Journal for Fisheries and Aquatic Sciences with authorship: Medeiros, A.S., & Quinlan, R. • Study design by ASM and RQ, data analysis by ASM, manuscript writing by ASM with editorial contributions from RQ. Chapter 4: A high resolution multi-proxy record of pronounced 20th century environmental change at Baker Lake, Nunavut • Manuscript submitted to the Journal of Paleolimnology with authorship: Medeiros, A.S., Friel, C.E., Finkelstein, S. & Quinlan, R. • Study design and chironomid data collection and analysis by ASM, diatom data collection and analysis by Charlotte E. Friel (CEF) and Sarah Finkelstein (SF) (University of Toronto), manuscript writing primarily by ASM with diatom-related contributions by CEF and SF, and editorial contributions from RQ. Appendix 1: Benthic biomonitoring in Arctic tundra streams; a community based approach in Iqaluit, Nunavut, Canada • Manuscript published in Arctic as follows: Medeiros, A.S., Luszczek, C.E., Shirley, J. & Quinlan, R. 2011. Benthic biomonitoring in Arctic tundra streams; a community based approach in Iqaluit, Nunavut, Canada. Arctic, 64(1): 59-72. • Study design by ASM, data collection by ASM, Jamal Shirley (JS) and CEL, data analysis primarily by ASM with contributions by CEL, manuscript writing by ASM with editorial contributions from JS, CEL and RQ. v Abstract An examination of the Chironomidae was conducted to determine the environmental gradients that may influence their distribution in the eastern Canadian Arctic. Subfossil chironomid head capsules, comprising 86 taxa, were sampled from surficial sediments of lakes and ponds that spanned from the tree-line in northern Manitoba across multiple regions of the territory of Nunavut, Arctic Canada. In addition, relationships between the limnology of lakes and ponds across these regions were examined. Pond systems ( < 2 m depth) were found to have a higher variability in temperature, nutrients, and major ions when compared to lake systems. There was also a significant difference between regions based on their limnology, however, overall relationships between environmental variables were similar in lakes and ponds across all regions. The water chemistry and environmental data were then compared to assemblages of taxa using multivariate analysis. The focus on both local and regional environmental gradients by sampling several systems within and between several regions allowed for the elucidation of a primary gradient that was represented by both temperature and total nitrogen. While temperature and trophic status were found to strongly influence the distribution of some taxa (e.g., Cladotanytarsus mancus-gr), partially constrained gradient analysis indicated that specific chironomid taxa could be used to indicate a primary response to climate regardless of trophic status. This allowed for a robust surface water paleo-temperature transfer function to be generated for application to sediment cores. A high-resolution examination of the subfossil remains of the Chironomidae was then conducted on a sediment core from Baker Lake, a large, deep Arctic lake in Canada. The core was sectioned at 0.5 cm resolution and Pb dating was used to establish a chronology. A downcore analysis of over 60 taxa indicated a pronounced gradual decline of several cold-water indicator taxa beginning at approximately 1940 AD and reaching 0% relative abundance at approximately 1990 AD. Several taxa indicative of warmer conditions first appear in sediments beginning in the 1940s and increase in abundance in more recent sediments. In addition, the arrival of Cladotanytarsus mancus gr., a warm- water adapted taxa indicative of higher nitrogen concentrations, in recent sediments (circa 1985 AD), increased to 12% of the total chironomid community by the surface sediment interval. The biostratigraphic results from Baker Lake were applied to the mid-summer surface water temperature inference model, and inference results indicated a 3°C increase in water temperature over the last 60 years. This also corresponded strongly to the instrumental record available since 1950. Thus, the gradual decline of cold-water adapted taxa, and subsequent increase of several taxa indicative of warmer regions, is a strong signal of recent environmental change within the area of Baker Lake, Nunavut. vn Table of Contents COPYRIGHT PAGE II CERTIFICATE PAGE Ill ACKNOWLEDGEMENTS IV CONTRIBUTIONS V ABSTRACT VI TABLE OF CONTENTS VIII LIST OF FIGURES XI LIST OF TABLES XIII LIST OF ABBREVIATIONS XIV CHAPTER 1: INTRODUCTION AND LITERATURE REVIEW 1 THESIS OBJECTIVES 8 CHAPTER 2: PATTERNS IN THE LIMNOLOGY OF LAKES AND PONDS ACROSS MULTIPLE LOCAL AND REGIONAL ENVIRONMENTAL GRADIENTS IN THE EASTERN CANADIAN ARCTIC 18 ABSTRACT 19 INTRODUCTION 20 METHODS 22 Field sampling