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Late Quaternary Vegetation and Climate Dynamics in Western Amazonia

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Late Quaternary Vegetation and Climate Dynamics in Western Amazonia Zentrum für Biodiversität und Nachhaltige Landnutzung Sektion Biodiversität, Ökologie und Naturschutz -Centre of Biodiversity and Sustainable Land Use- Section: Biodiversity, Ecology and Nature Conservation Late Quaternary Vegetation and Climate Dynamics in Western Amazonia Dissertation For the award of the degree ‚Doctor of Philosophy‛ (Ph.D. Division of Mathematics and Natural Sciences) Of the Georg-August-University of Göttingen Within the doctoral program Biodiversity, Ecology and Evolution Submitted by Paula A. Rodríguez-Zorro From Sogamoso (Colombia) Göttingen, 2017 Thesis committee Prof. Dr. Hermann Behling (Department of Palynology and Climate Dynamics / A.-v.-H. Institute for Plant Sciences) Prof. Dr. Erwin Bergmeier (Department of Vegetation and Phytodiversity Analysis/ A.-v.-H. Institute for Plant Sciences) Prof. Dr. Markus Hauck (Department of Plant Ecology/ A.-v.-H. Institute for Plant Sciences) Members of the examination committee Prof. Dr. Hermann Behling (Department of Palynology and Climate Dynamics / A.-v.-H. Institute for Plant Sciences) Dr. Thomas Giesecke (Department of Palynology and Climate Dynamics / A.-v.-H. Institute for Plant Sciences) Prof. Dr. Erwin Bergmeier (Department of Vegetation and Phytodiversity Analysis/ A.-v.-H. Institute for Plant Sciences) Prof. Dr. Markus Hauck (Department of Plant Ecology/ A.-v.-H. Institute for Plant Sciences) Prof. Dr. Holger Kreft (Free floater research group-Biodiversity, Macroecology & Biogeography) Prof.Dr. Alexander Schmidt (Department of Geobiology/Evolution of Landplants & Development of Terrestrial Ecosystems) Date of oral examination: 15.03.2017 Para mi familia Table of contents Preface ................................................................................................................................... 9 Acknowledgements ........................................................................................................... 11 Summary ............................................................................................................................. 13 CHAPTER 1 ........................................................................................................................ 15 General Introduction ..................................................................................................... 15 1.1 Study Sites ............................................................................................................ 16 1.2 Geology of the Amazon basin ........................................................................... 17 1.3 Hydrology ............................................................................................................ 18 1.4 Climate .................................................................................................................. 19 1.5 Vegetation ............................................................................................................ 20 1.6 Pollen Analyses ................................................................................................... 22 1.6.1 Preparation of pollen samples ................................................................... 23 1.7 Multi-Proxy Studies ............................................................................................ 23 1.8 Late Quaternary Palaeoecology in Western Amazonia ................................ 24 1.8.1 The Early Holocene ..................................................................................... 24 1.8.2 The Mid-Holocene ....................................................................................... 25 1.8.3 The late Holocene ........................................................................................ 25 1.8.4 Anthropogenic influence ............................................................................ 25 1.9 Aim and Objectives of the Project .................................................................... 27 1.10 References ......................................................................................................... 28 2 CHAPTER 2 ................................................................................................................ 35 Vegetation changes and human impact inferred from an oxbow lake in southwestern Amazonia, Brazil since the 19th century. .......................................... 35 Abstract ........................................................................................................................... 36 2.1 Introduction ......................................................................................................... 37 2.2 Study area ............................................................................................................ 39 2.3 Materials and methods ....................................................................................... 40 2.4 Results ................................................................................................................... 42 2.4.1 Stratigraphy .................................................................................................. 42 2.4.2 Chronology ................................................................................................... 42 2.4.3 Pollen diagram ............................................................................................. 43 2.4.4 XRF analysis ................................................................................................. 46 2.5 Interpretation and discussion ........................................................................... 47 2.5.1 Chronology of Lago Amapá core .............................................................. 47 2.5.2 XRF record .................................................................................................... 49 2.5.3 Pollen record................................................................................................. 50 2.6 Conclusions .......................................................................................................... 53 2.7 Acknowledgements ............................................................................................ 53 2.8 References ............................................................................................................ 54 3 CHAPTER 3 ................................................................................................................ 63 Mid-Holocene vegetation dynamics with an early expansion of Mauritia flexuosa palm trees inferred from the Serra do Tepequém in the savannas of Roraima State in Amazonia, northwestern Brazil. ................................................... 63 Abstract ........................................................................................................................... 64 3.1 Introduction ......................................................................................................... 65 3.2 Study Area ........................................................................................................... 67 3.3 Material and Methods ........................................................................................ 69 3.4 Results ................................................................................................................... 71 3.4.1 Stratigraphy and Chronology .................................................................... 71 3.5 Description of the pollen diagram .................................................................... 74 3.5.1 Pollen zone 1 T1 (200-100 cm; 20 samples) .............................................. 75 3.6 Interpretation and Discussion ........................................................................... 78 3.6.1 Chronology of the sediment core Serra do Tepequém .......................... 78 3.6.2 The mid-Holocene at Serra do Tepequém ............................................... 79 3.6.3 A possible human impact during the mid-Holocene ............................. 82 3.6.4 The mid-Holocene at Roraima savannas in Brazil .................................. 83 3.6.5 A regional overview of the mid-Holocene vegetation changes in northern savannas in South America ..................................................................... 84 3.7 Conclusions .......................................................................................................... 87 3.8 Acknowledgements ............................................................................................ 88 3.9 References ............................................................................................................ 89 3.10 Supplementary material ................................................................................. 96 4 CHAPTER 4 ................................................................................................................ 99 Early and late Holocene Vegetation Dynamics in the Rio Negro Amazon Region and Resilience of Rainforest to Climate Change and River Dynamics .................. 99 Abstract ......................................................................................................................... 100 4.1 Introduction ....................................................................................................... 101 4.2 Study area .......................................................................................................... 103 4.3 Methods .............................................................................................................. 105 4.4 Results
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