Climate and Vegetation Change in Late Pleistocene Central Appalachia: Evidence From

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Climate and Vegetation Change in Late Pleistocene Central Appalachia: Evidence From Climate and Vegetation Change in Late Pleistocene Central Appalachia: Evidence from Stalagmites and Lake Cores A thesis presented to the faculty of the College of Arts and Sciences of Ohio University In partial fulfillment of the requirements for the degree Master of Science Kelli W. Baxstrom May 2019 © 2019 Kelli W. Baxstrom. All Rights Reserved. 2 This thesis titled Climate and Vegetation Change in Late Pleistocene Central Appalachia: Evidence from Stalagmites and Lake Cores by KELLI W. BAXSTROM has been approved for the Department of Geological Sciences and the College of Arts and Sciences by Gregory S. Springer Associate Professor of Geological Sciences Joseph Shields Interim Dean, College of Arts and Sciences 3 ABSTRACT BAXSTROM, KELLI W., M.S., May 2019, Geological Sciences Climate and Vegetation Change in Late Pleistocene Central Appalachia: Evidence from Stalagmites and Lake Cores Director of Thesis: Gregory S. Springer This thesis uses a multi-proxy approach involving pollen and speleothem isotopes, to determine how climate events and vegetation changes influenced biomes in the Appalachian Mountains of East Central North America (ECNA) during the Last Glacial Maximum and glacial retreat leading into the Holocene. To do this, a stalagmite from Culverson Creek Cave in West Virginia was collected and analyzed for carbon and oxygen isotopes, and two pollen and macrofossil records were collected and analyzed from Browns Pond and Pancake Field in Virginia. The Browns Pond pollen record was previously published, but the Pancake Field pollen record is novel in partnership with the U. S. Geological Survey in Reston, VA. The records helped reconstruct the history of prairie development and transition into woodland from 27-10 thousand years before present. These two types of records were compared to construct a palaeoecological account of ECNA. Results show that ECNA vegetation closely tracked climate events, including precipitation and temperature changes, that affected North America and the Northern Hemisphere in general, but the Appalachian Mountains provided refugia for some species. 4 DEDICATION For Bryce, Emily, Leo, and Archie. Success excerpt from “The Ladder of Saint Augustine”: The heights by great men reached and kept Were not attained by sudden flight, But they, while their companions slept, Were toiling upward in the night. – Henry Wadsworth Longfellow (1807-1882) 5 ACKNOWLEDGMENTS Thank you to my advisor Gregory S. Springer for introducing me to the wonderful world of caving, and for patiently guiding me through endless drafts. Thank you to Drew Hall for being a sounding board, caving partner, and sanity checker for two years. Thank you to the Cave Conservancy of the Virginias, Ohio University’s Geological Sciences Alumni Grant, and Ohio University’s Student Enhancement Award for the funding of this project. 6 TABLE OF CONTENTS Page Abstract ............................................................................................................................... 3 Dedication ........................................................................................................................... 4 Acknowledgments............................................................................................................... 5 List of Tables ...................................................................................................................... 8 List of Figures ..................................................................................................................... 9 Chapter 1: Introduction ..................................................................................................... 10 Stalagmites .................................................................................................................. 11 Relating Modern Climate to the Past .................................................................... 12 Plant Associations ....................................................................................................... 14 Implications................................................................................................................. 19 Research Objectives .................................................................................................... 21 Chapter 2: Geologic Setting .............................................................................................. 23 Greenbrier Geology .................................................................................................... 23 Karst and Speleothem Stable Isotopes ........................................................................ 24 Chapter 3: Methods ........................................................................................................... 31 Stalagmite Collection and Processing ......................................................................... 31 230Th Age Dating......................................................................................................... 31 Stable Isotopic Analysis .............................................................................................. 32 Chronology ................................................................................................................. 32 Pollen .......................................................................................................................... 33 Browns Pond ......................................................................................................... 33 Pancake Field ........................................................................................................ 34 Statistical Analyses ............................................................................................... 36 Chapter 4: Results ............................................................................................................. 38 Stalagmite ................................................................................................................... 38 230Th Age Dates .......................................................................................................... 39 Stable Isotope Analysis ............................................................................................... 42 Browns Pond ............................................................................................................... 45 Pancake Field .............................................................................................................. 48 Statistics ...................................................................................................................... 48 7 Chapter 5: Discussion ....................................................................................................... 55 Stalagmite Interpretations ........................................................................................... 55 The Last Glacial Maximum .................................................................................. 55 Glacial Retreat ...................................................................................................... 59 Correlations Between CCC-003 and Pollen ............................................................... 63 The Last Glacial Maximum .................................................................................. 63 Glacial Retreat ...................................................................................................... 66 Implications for Megafauna and Humans ............................................................. 72 Conclusions ....................................................................................................................... 75 References ......................................................................................................................... 78 Appendix A: U/TH Data Table and 230Th Ages for CCC-003 ....................................... 102 Appendix B: Pancake Field Percent Abundance ............................................................ 105 Appendix C: Neotoma Data ............................................................................................ 108 8 LIST OF TABLES Page Table 1. Timeline of climate events and dominant vegetation ......................................... 71 9 LIST OF FIGURES Page Figure 1. Holocene mean seasonal summer and wintertime ensembles ........................... 13 Figure 2. Map of sampling locations ................................................................................ 23 Figure 3. Subsurface karst system .................................................................................... 25 Figure 4. Stalagmite creation ............................................................................................ 27 Figure 5. Climate controls that affect δ18O variations ...................................................... 29 Figure 6. Pancake Field..................................................................................................... 35 Figure 7. Halved CCC-003 and 230Th sample locations ................................................... 38 Figure 8a. StalAge original age data ................................................................................. 40 Figure 8b. StalAge final age model with original errors .................................................. 41 Figure 8c. StalAge final age model with screened errors ................................................. 42 18 13 Figure 9. δ O and δ C with corresponding linear correlation coefficient
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