Soil carbon sequestration and CO_1tn2 flux partitioning [Elektronische Ressource] : isotopic patterns, models, applications / von Volker Hahn

Soil carbon sequestration and CO flux partitioning 2Isotopic patterns, models, applications Dissertation zur Erlangung des akademischen Grades doctor rerum naturalium (Dr. rer. nat.) vorgelegt dem Rat der Chemisch-Geowissenschaftlichen Fakultät der Friedrich-Schiller-Universität Jena von Volker Hahn, geboren am 4. Mai 1974 in Bielefeld Gutachter: 1. 2. 3. Table of contents Table of contents 1 Introduction 1 2 Modeling the amount and turnover of active soil organic carbon 4 2.1 Introduction 4 2.2 Methods 5 2.3 Results 12 2.4 Discussion 18 3 Separating heterotrophic and autotrophic soil respi-ration 21 3.1 Introduction 21 3.2 Methods 23 3.3 Results 29 3.4 Discussion 33 4 Isotopic composition of soil CO and soil respired 2CO in European forests along a latitudinal and two 2age gradients 36 4.1 Introduction 36 4.2 Methods 38 4.3 Results 40 4.4 Discussion 52 5 Concluding discussion 57 6 Abstract 61 7 References 64 8 Acknowledgements 74 9 Appendix 75 Introduction 11 Introduction Fossil fuel burning, cement production and land-use change have caused an increase of atmospheric CO mixing ratios from approximately 280 ppm at pre-industrial level to 2approximately 370 ppm today. This rise in atmospheric CO is believed to be one of the 2major causes for global warming (IPCC 2001).