ALBERT

Anmerkung: Dissertation, Universität Potsdam, 2014 , Table of contents I - Abstract II - Zusammenfassung Chapter 1 - Introduction 1.1. Introduction 1.1.1 Motivation 1.1.2 Organisation of thesis 1.1 Scientific background 1.2.1 Arctic and wetland bryophytes 1.2.2 Bryophyte remains as palaeo-environmental indicators 1.2.3 Regional setting 1.3 Objectives ofthe thesis 1.4 Overview of the manuscripts 1.5 Contribution of the authors Chapter 2 - Manuscript #1 Abstract 2.1 Introduction 2.2 Geographic setting 2.3 Materials and methods 2.3.1 Fieldwork 2.3.2 Radiocarbon dating 2.3.3 Geochemical, stable carbon isotope, and granulometric analyses 2.3.4 Analyses of moss remains and vascular plant macrofossils 2.3.5 Pollen analysis 2.3.6 Diatom analysis 2.3.7 Statistical analysis 2.4 Results 2.4.1 High-resolution spatial characteristics oft the investigated polygon and vegetation pattern 2.4.2 Geochronology and age-depth relationships 2.4.3 General properties of the sedimentary fill 2.4.4 Bioindicators 2.4.5 Characterization oftwo different types of polygon pond sediment 2.5. Discussion 2.5.1 Small-scale spatial structure of polygons 2.5.2 Age-depth relationships 2.5.3 Proxy value of the analysed parameters 2.5.4 The general polygon development 2.5.5 Polygon development as a function of external controls and internal adjustment mechanisms 2.6 Conclusions Chapter 3 - Manuscript #11 Abstract 3.1 Introduction 3.2 Material und methods 3.2.1 Regional setting 3.2.3 Field methods and environmental data collection 3.2.4 Data analysis 3.3 Results 3.3.1 Major characteristics of the investigated polygons 3.3.2 Vegetation cover and its relationships with micro-relief and vegetation type 3.3.3 Vegetation alpha-diversity and its relationship with micro-relief and vegetation type 3.3.4 Vegetation composition and its relationship with micro-relief and vegetation type 3.4 Discussion 3.4.1 Patterns of cover, alpha-diversity and compositional turnover of vascular plants and bryophytes along the rim-pond transect (local-scale) 3.4.2 Patterns of cover, alpha-diversity and compositional turnover of vascular plants and bryophytes along the regional-scale forest-tundra transect 3.4.3 Indicator potential ofvascular plant and bryophyte remains from polygonal peats for the reconstruction of local hydrological and regional vegetation changes 3.4.4. Implications of the performed vegetation transect studies for future Arctic warming 3.5 Acknowledgements 2.4.4 Bioindicators 2.4.5 Characterization of two different types of polygon pond sediment 2.5. Discussion 2.5.1 Small-scale spatial structure of polygons 2.5.2 Age-depth relationships 2.5.3 Proxy value of the analysed parameters 2.5.4 The general polygon development 2.5.5 Polygon development as a function of external controls and internal adjustment mechanisms 2.6 Conclusions Chapter 3 - Manuscript #II Abstract 3.1 Introduction 3.2 Material und methods 3.2.1 Regional setting 3.2.3 Field methods and environmental data collection 3.2.4 Data analysis 3.3 Results 3.3.1 Major characteristics of the investigated polygons 3.3.2 Vegetation cover and its relationships with micro-relief and vegetation type 3.3.3 Vegetation alpha-diversity and its relationship with micro-relief and vegetation type 3.3.4 Vegetation composition and its relationship with micro-relief and vegetation type 3.4 Discussion 3.4.1 Patterns of cover, alpha-diversity and compositional turnover of vascular plants and bryophytes along the rim-pond transect (local-scale) 3.4.2 Patterns of cover, alpha-diversity and compositional turnover of vascular plants and bryophytes along the regional-scale forest-tundra transect 3.4.3 Indicator potential of vascular plant and bryophyte remains from polygonal peats for the reconstruction of local hydrological and regional vegetation changes 3.4.4. Implications of the performed vegetation transect studies for future Arctic warming 3.5 Acknowledgements Chapter 4 - Manuscript #3 Abstract 4.1 Introduction 4.2 Material and methods 4.2.1 Sites 4.2.2 Sampling 4.2.3 Investigated moss species 4.2.4 Measurements 4.2.5 Statistical Tests 4.3 Results 4.4 Discussion Chapter 5 - Discussion 5.1 Bryophytes of polygonal landscapes in Siberia 5.1.1 Modern bryophytes in the Siberian Arctic 5.1.2 Biochemical and isotopic characteristics of mosses 5.1.3 Reliability and potential of fossil bryophyte remains as palaeoproxies 5.2 Dynamics of low-centred polygons during the late Holocene 5.3 Outlook Appendix I - Preliminary Report Motivation Material and methods Results and first interpretation Appendix II Additional tables and figures of manuscript #1 Appendix III Additional figures of manuscript #2 Appendix IV - Quantitative approach of Standard Moss Stem (SMS3) Bibliography Acknowledgements Eidesstattliche Erklärung