ALBERT

Note: Dissertation, Universität Potsdam, 2018 , Table of Content I. Abstract II. Deutsche Zusammenfassung 0 Preface 1 Scientific Background 1.1 Paleoenvironmental changes since the gLGM in arid Central Asia and north-western High Asia 1.1.1 Paleoclimatic changes 1.1.2 Lake level fluctuations following climatic changes 1.1.3 Inferred terrestrial vegetation responses to environmental changes and possible human impact 1.2 The role of proxy records in tracing environmental changes 1.2.1 Archives and Proxies investigated in environmental studies in Central Asia 1.2.2 Limnological systems as environmental archives 1.2.3 The multiproxy approach as a tool to decipher environmental change 1.3 Study area 1.4 Material and Method Overview 1.4.1 Field based sampling 1.4.2 Outline of material and methods 1.5 Aim and objectives ofthis thesis 1.6 Thesis outline 1.7 Contribution of the authors 1.7.1 Manuscript I - published 1.7.2 Manuscript II - published 1.7.3 Manuscript III - published 1.7.4 Manuscript IV - in preparation 2 Manuscript I Climatic and limnological changes at Lake Karakul (Tajikistan) during the last ~29 cal ka 2.1 Abstract 2.2 Introduction 2.3 Study Area 2.4 Material and methods 2.4.1 Fieldwork 2.4.2 Laboratory analysis 2.5 Results 2.5.1 Age-depth relationship in core KK12-1 2.5.2 TIC, TOC, TOC/TN, δ18Ocarb and δ13CCarb 2.5.3 Grain-size distribution and results ofend-member modelling 2.5.4 XRF data 2.5.5 Ordination results of sediment parameters 2.6 Discussion 2.6.1 Paleoenvironmental indicators from sediment variables 2.6.2 Implications ofthe Lake Karakul sediment record 2.6.3 Linking lake internal development to climate change 2.7 Conclusions 2.8 Acknowledgements 2.9 Data availability 3 Manuscript II Aquatic macrophyte dynamics in Lake Karakul (Eastern Pamir) over the last 29 cal ka revealed by sedimentary ancient DNA and geochemical analyses of macrofossil remains 3.1 Abstract 3.2 Introduction 3.3 Material and Methods 3.3.1 Sample acquisition and treatment 3.3.2 Genetic approach 3.3.3 Elemental isotopic analyses ofaquatic macrophyte remains 3.4 Results 3.4.1 Macrophyte records along lake depth transects in Lake Karakul 3.4.2 Submerged plant content 3.4.3 Ancient DNA analyses 3.4.4 C, N, δ13C and δ15N of Stuckenia cf. pamirica remains 3.5 Discussion 3.5.1 Assessment of aDNA and chemical aquatic macrophyte data as proxies for the macrophyte composition and the paleo-productivity 3.5.2 Changes of past submerged plant composition and productivity and potential drivers 3.6 Conclusions 3.7 Acknowledgements 3.8 Data Availability 4 Manuscript III Radiocarbon and optical stimulated luminescence dating of sediments from Lake Karakul, Tajikistan 4.1 Abstract 4.2 Introduction 4.3 Regional setting 4.4 Methods 4.4.1 Collection and correlation of cores 4.4.2 Radiocarbon dating 4.4.3 Optically stimulated luminescence (OSL) dating 4.4.4 Establishment ofage-depth model 4.4.5 Investigation of exposed lake sediments 4.5 Results 4.6 Discussion 4.6.1 Recovered sediments and correlation ofcores from Lake Karakul 4.6.2 Age-depth model, and assessment of radiocarbon and OSL age data 4.6.3 Significance ofexposed sediments at section KK13-S1 4.6.4 Implications ofthe chronological data 4.7 Conclusion 4.8 Acknowledgements 5 Manuscript IV Vegetation change in the Eastern Pamir Mountains inferred from Lake Karakul pollen spectra of the last 28 ka 5.1 Abstract 5.2 Introduction 5.3 Study site 5.4 Material and Methods 5.4.1 Sediment cores and chronology 5.4.2 Pollen sample preparation and pollen analyses 5.4.3 Pollen data treatment 5.5 Results 5.5.1 Composite core (KK12-1/2; 27.6 cal ka BP to present) 5.5.2 Short core TAJ-Kar-08-lB 5.6 Discussion 5.6.1 Interpretation of pollen data 5.6.2 Terrestrial vegetation change in the Eastern Pamir Mountains in response to past climate change 5.7 Conclusions 5.8 Acknowledgements 5.9 Data Availability 6 Synthesis 6.1 Proxy evaluation 6.1.1 Age-depth relationship 6.1.2 Limnological proxies 6.1.3 Terrestrial proxies 6.2 The potential of Lake Karakul as archive for long term environmental change in the Eastern Pamir 6.3 Climate and moisture availability changes over time - inferred from sedimentary proxies 6.4 Assessment ofthe aquatic macrophyte composition and paleoproductivity within Lake Karakul 6.5 Inferred terrestrial vegetation changes as responds to climatic changes over the last 28 cal ka 6.6 Comparison inferred regional vegetation, lake internal and lake external variations and changes in climate reconstructed in other studies 6.6.1 Pre- gLGM and global Last Glacial Maximum (27.6 to 19 cal ka BP) 6.6.2 Late glacial 6.6.3 Early to middle Holocene 6.6.4 Middle to late Holocene 6.7 Outlook 7 Appendix 7.1 Supplementary information for Manuscript I 7.2 Supplementary information for Manuscript II 7.3 Supplementary information for Manuscript III 8 References Danksagung Eldesstattliche Erklärung