Calibration and Interpretation of Holocene Paleoecological Records of Diversity from Lake Tanganyika, East Africa Item Type text; Dissertation-Reproduction (electronic) Authors Alin, Simone Rebecca Publisher The University of Arizona. Rights Copyright © is held by the author. Digital access to this material is made possible by the Antevs Library, Department of Geosciences, and the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author or the department. Download date 05/10/2021 07:51:11 Link to Item http://hdl.handle.net/10150/231412 CALIBRATION AND INTERPRETATION OF HOLOCENE PALEOECOLOGICAL RECORDS OF DIVERSITY FROM LAKE TANGANYIKA, EAST AFRICA by Simone Rebecca Alin Copyright © Simone Rebecca Alin 2001 A Dissertation Submitted to the Faculty of the DEPARTMENT OF GEOSCIENCES In Partial Fulfillment of the Requirements For the Degree of DOCTOR OF PHILOSOPHY In the Graduate College THE UNIVERSITY OF ARIZONA 2001 r,y . .a. i`- { . +. -- /i THE UNIVERSITY OF ARIZONA GRADUATE COLLEGE As members of the Final Examination Committee, we certify that we have read the dissertation prepared bySimone Rebecca Alin entitled Calibration and Interpretation of Holocene Paleoecological Records of Diversity from Lake Tanganyika, East Africa and recommend that it be accepted as fulfilling the dissertation requieurent for t Degree of Doctor of Philosophy '/57/Gi An re, Cohen Date C Q CA (r 2svF Karl Flessa Date l /C)/ Jonathan i1Ferpeck Date Peter Rein th Date Viz& I l Robert Robichaux Date Final approval and acceptance of this dissertation is contingent upon the candidate's submission of the final copy of the dissertation to the Graduate College. I hereby certify that I have read this dissertation prepared undermy direct'on and recommend that it be accepted as fulfilling the dissertation requi t- ment . ,,-Th l/ lL7 /6l Dissertation Director Andresv Cohen Dat'e 3 STATEMENT BY AUTHOR This dissertation has been submitted in partial fulfillment of requirements for an advanced degree at The University of Arizona and is deposited in the University Library to be made available to borrowers under rules of the Library. Brief quotations from this dissertation are allowable without special permission, provided that accurate acknowledgment of source is made. Requests for permission for extended quotation from or reproduction of this manuscript in whole or in part may be granted by the copyright holder. 4 ACKNOWLEDGMENTS This dissertation could not have been completed without the assistance and encouragement of many individuals and organizations. I was fortunate to have a supportive, accessible, and inspiring dissertation committee. I am grateful to Andrew Cohen for giving me the opportunity to work on a truly exceptional ecosystem and to live in Africa, a long -time dream of mine. His enthusiasm for Lake Tanganyika is contagious, and his breadth of experience there is impressive. Karl Flessa has consistently offered excellent advice and feedback; his tutelage in the art of scientific communication has been particularly valuable. Peter Reinthal and Rob Robichaux brought an important ecological perspective to my committee and have served as inspiring examples to me of people who have successfully melded their academic interests in biological conservation with effective field efforts. Jonathan Overpeck provided valuable perspective on paleoclimatic /global change issues. Les Kaufman consistently asked difficult, thought -provoking questions. I also thank Lisa Graumlich for serving as an excellent role model and supportive mentor early in my graduate career; Owen Davis for help on numerous occasions; John Lundberg and Lucinda McDade for rigorous classes, discussions, and field excursions; David Dettman for excellent guidance on all things carbon; and Julie Cole for stimulating discussions and seminars. Catherine O'Reilly's perseverance was essential in ensuring regular data collection in the field. In addition, Jeff Houser, Ruben Shapola, Kimambo, Chatta, Ibrahim, Chale, and Tony Thompson facilitated our safe diving. Mr. Chitamwebwa generously allowed me to use Tanzanian Fisheries Research Institute facilities in Kigoma. The Lake Tanganyika Biodiversity Project, particularly Kelly West, Graeme Patterson, and Andy Menz; Tanzanian Commission for Science and Technology; Tanzanian Immigration Agency; and Tanzania National Parks provided invaluable logistical assistance and necessary permits. I thank the Department of Geosciences staff and Paul Pronze and Dorian Voorhees at the Graduate College for logistical and bureaucratic assistance; Blackwell Publishing for permission to include Appendix A in my dissertation; and Vera Markgraf and Alex Wolfe for providing me laboratory space at INSTAAR (CU- Boulder). I received generous financial support for my dissertation research froman NSF Graduate Research Fellowship, Analysis of Biological Diversification RTG Fellowship, National Security Education Program Graduate International Fellowship, Graduate College Dean's Dissertation Fellowship, Wilson R. Thompson Scholarship, Geological Society of America, Graduate and Professional Student Council Travel Grant Fund, Graduate College Final Project Fund, Women in Science and Engineering Travel Grant Fund, organizers of several meetings, and NSF grants EAR -9627766 and ATM -9619458. Finally, I am tremendously grateful for the intellectual stimulation, moralsupport, and recreational opportunities provided by Annika Alin, Jonathan Fost, Carmie Garzione, Damian Hodkinson, Joy and Nick Bader, Sharon Hall, Stacie Gibbins, Dena Smith, Catherine O'Reilly, Mark Rollog, Steve Young, Dave Goodwin, Tim Shanahan,Kris Kerry, Eric Jensen, Elise Pendall, and Nathan English,among others. Finally, I am deeply grateful to Winston Wheeler; his support, intelligence, andsense of humor have gotten me through the past few months with a smileon my face. 5 DEDICATION I dedicate this dissertation to my parents, Elizabeth Atly, Jack Alin, Susie Alin, and Carlos Reyes, for their bottomless reserves of support for me. Their lifelong encouragement for me to follow my dreams, their friendship, and often their material support have made this endeavor not just possible, but very rewarding. I am especially grateful that my graduate studies gave me the opportunity to travel in Tanzania with both my father and my mother. 6 TABLE OF CONTENTS Page LIST OF FIGURES 10 LIST OF TABLES 11 ABSTRACT 12 CHAPTER 1: INTRODUCTION 14 Background and Statement of the Research Problem .14 Format of the Dissertation 17 CHAPTER 2: PRESENT STUDY 20 CHAPTER 3: A HIGH -RESOLUTION RECORD OF NATURAL ENVIRONMENTAL CHANGE AND PALEOECOLOGICAL RESPONSE IN LAKE TANGANYIKA, EAST AFRICA, SINCE THE LATE GLACIAL .24 Abstract 24 Introduction 25 Methods 28 Core Collection and Sampling 28 Laboratory Analyses 29 Results .33 Geochronology and Sedimentology Data 33 Elemental and Stable Isotope Data 35 Diagenesis 38 Paleoecological Data 39 Discussion 41 Sedimentary Environment and Preservation Conditions 41 Environmental Variability and Paleoecological Response .42 Temporal Trend in SOM Preservation: Signal of Degradation or Primary Productivity ? 48 Charcoal and Lake Level Change 49 Conclusions 52 CHAPTER 4: CONCLUSIONS 77 Microinvertebrate Paleoecology and Conservation 77 Ostracods as Indicators of Environmental Change ..79 APPENDIX A: EFFECTS OF LANDSCAPE DISTURBANCE ON ANIMAL COMMUNITIES IN LAKE TANGANYIKA, EAST AFRICA 85 Abstract 87 Introduction 88 Methods 89 7 TABLE OF CONTENTS-Continued Page Study Sites and Data Collection 89 Evaluation of Water Quality 90 Faunal Censuses 90 Data Analysis 91 Results 91 Water Quality 91 Faunal Censuses and Rarefaction 93 Fish Trophic Analyses .93 Similarity Indices and Community Structure ..93 Discussion 94 Similarity Indices and Community Structure ..95 Ecological Tolerances .95 Lake Basin Parameters and Conservation 96 Caveats 96 Conclusions 96 Acknowledgments 97 Literature Cited 97 Appendix 1 ..99 Appendix 2 .101 Appendix 3 102 APPENDIX B: THE LIVE, THE DEAD, AND THE VERY DEAD: TAPHONOMIC CALIBRATION OF THE PALEOECOLOGICAL RECORD IN LAKE TANGANYIKA, EAST AFRICA 104 Abstract ..104 Introduction 105 Background on Study Area 107 Study Area and Methods 109 Sampling 109 Data Analysis 111 Results 115 Sedimentological and Radiocarbon Data for Cores 115 Characteristics of Ostracod Assemblages ..116 Fidelity of Death and Fossil Assemblages to the Living .120 Analysis of Core Interval Re- Sampling 122 Ordination 123 Discussion .126 Preservation of Life Assemblage Attributes in Death and Fossil Assemblages.....126 Fidelity Metrics 129 Sampling Efficiency 130 8 TABLE OF CONTENTS-Continued Page Scaling Issues and Equivalence of Fish and Ostracod Community Dynamics...... 132 Novel Contributions of Paleoecological Observations to Conservation Biology... 135 Conclusions 136 Acknowledgments 136 References ..160 APPENDIX C: PALEOENVIRONMENTAL RECORDS OF LANDSCAPE DISTURBANCE AT GOMBE STREAM NATIONAL PARK, AFRICA 165 Abstract ..165 Body of Paper 166 Acknowledgments . 171 References . 182 APPENDIX D: LIST OF ABBREVIATIONS USED FOR SPECIES NAMES IN ALL OSTRACOD SPECIES ABUNDANCE DATA MATRICES . 184 APPENDIX E: RAW DATA FROM CORE LT97 -56V COLLECTED FROM 56 M WATER DEPTH NEAR MGONDOZI, TANZANIA 187 Species abundance data for fossil assemblages ..187 Taphonomic and ostracod abundance data for LT97 -56V fossil assemblages 190 Grain size distribution for samples from core LT97 -56V