Microbial perspectives of the methane cycle in permafrost ecosystems in the Eastern Siberian Arctic [Elektronische Ressource] : implications for the global methane budget / von Dirk Wagner

Dirk Wagner

Sujets

• Biologie

Informations

• Publié par: universitat_potsdam
• Publié le: 01 janvier 2007
• Nombre de lectures: 38
• Langue: English
• Poids de l'ouvrage: 8 Mo

Extrait

Microbial Perspectives
of the Methane Cycle in Permafrost Ecosystems
in the Eastern Siberian Arctic

– Implications for the Global Methane Budget –










Habilitationsschrift










eingereicht an der
Mathematisch-Naturwissenschaftlichen Fakultät
der Universität Potsdam





von
Dr. Dirk Wagner










Potsdam, Januar 2007








































Gekürzte Fassung der Habilitationsschrift
elektronisch veröffentlicht auf dem
Publikationsserver der Universität Potsdam:
http://opus.kobv.de/ubp/volltexte/2007/1543/
urn:nbn:de:kobv:517-opus-15434
[http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-15434]

Die vollständige Fassung befindet sich als gedruckte Ausgabe im Bestand der
Universitätsbibliothek Potsdam.









































Dr. rer. nat. Dirk Wagner
Alfred-Wegener-Institut für Polar- und Meeresforschung
Forschungsstelle Potsdam
Telegrafenberg A43
14473 Potsdam

E-Mail: [e-mail]


Home Address

Thaerstraße 57
14469 Potsdam


3


PREFACE


This thesis (Habilitation) highlights the findings of several years of research work in
permafrost environments of the Siberian Arctic. The studies were carried out to gain
insights into the carbon dynamics of tundra wetlands – mainly the methane fluxes –
and the contribution of the microbial processes and communities to the terrestrial
methane cycle. Furthermore, the response of microorganisms to the environmental
conditions of permafrost was investigated. Field research and sampling were carried
out during eight expeditions to the Lena Delta and Cape Mamontov Klyk at the
Laptev Sea coast. Experiments and analytical work was mainly accomplished at the
Alfred Wegener Institute for Polar and Marine Reseach (AWI), Research Unit
Potsdam. The study was financed through the AWI Research Program MARCOPOLI,
and by the Bundesministerium für Bildung und Forschung (BMBF) and by the
Deutsche Forschungsgemeinschaft (DFG) through the following projects:

• BMBF project: Russian-German Cooperation: SYSTEM LAPTEV SEA 2000:
“Balance of Trace Gas Fluxes and Processe Studies within the Methane Cycle
in Permafrost Regions” (03G0534) by E.-M. Pfeiffer
• BMBF project: Russian-German Cooperation: SYSTEM LAPTEV SEA 2000 –
Synthesis: “Terrestrial Dynamics in the Laptev Sea Region” (03G0534) by
H.-W. Hubberten
• BMBF project: Process Studies on Permafrost Dynamics in the Laptev Sea:
„Microbial Processes in Permafrost: Anaerobic Microbial Carbon
Decomposition“ (03G0589) by E.-M. Pfeiffer with the assistance of E. Spieck,
and D. Wagner
• DFG project „Tolerance Limits of Methanogenic Life in Terrestrial Permafrost“
(WA 1554/1-1 and WA 1554/1-2) within the priority program „Mars and the
Terrestrial Planets“ by D. Wagner

The thesis is composed of three parts: In the first part (chapters 1 and 2) an
Introduction of the research topic and an Overview of the different studies, their
present status and my personal contribution to each publication is given.

The second part, which is organized in four thematic chapters (3-6) comprises
fourteen research article relevant to the topic of the thesis. Eleven articles were
published or are in press in peer-reviewed international journals, complemented by
three submitted manuscripts. I am the first author of five papers. To the other articles
4
(two of them are two-authored papers), I have made essential contributions in the
form of text passages, field work, data sets or interpretations. The references of the
Introduction and Synthesis are summarized with those of the publications at the end
of the thesis, in order to avoid statement of the same references several times.

The thesis is terminated with a third part (chapters 7 and 8), in which the most
important findings and conclusions are summarised. In the Synthesis the results of
the publications to the microbially driven carbon dynamics and the tolerance of the
microorganisms to extreme environmental condition are combined with other studies
from permafrost regions and discussed in the scope of its significance for the global
methane budget. Finally, the Conclusions derived from the studies are presented.

5Contents Methane Cycle in Permafrost Ecosystems



Contents


Abstract…...……………………………………………………………............ 8

Zusammenfassung………………………………………………………….... 10

1 General Introduction…………………………….……………………………. 12
1.1 Significance of Permafrost Ecosystems for the Global Methane
Budget…………..…..……………………….…………………………… 12
1.2 Astrobiological Aspects of Permafrost Environments….…….….…... 15
1.3 Objectives and Research Strategy……….……………..…………….. 16
1.4 Study Area…………..…………………….……………………………... 18
1.5 Expeditions…….…………………………………………………………. 21

2 Overview of the Publications……….…………..…..…………….………… 24

3 Methane Release from Siberian Tundra Environments……….……….. 29
3.1 Methane Emission from Siberian Arctic Polygonal Tundra: Eddy
Covariance Measurements and Modeling……………………..…….. 29
3.2 Effect of Microrelief and Vegetation on Methane Emission from wet
Polygonal Tundra, Lena Delta, Northern Siberia………..…………… 44
3.3 Land Cover Classification of Tundra Environments in the Arctic
Lena Delta Based on Landsat 7 ETM+ Data and its Application for
Upscaling of Methane Emissions…………………..………………….. 63

4 Permafrost Ecosystems and Their Microbial Processes...………….… 77
4.1 Element Redistribution Along Hydraulic and Redox Gradients of
Low-Centered Polygons, Lena Delta, Northern Siberia…….……….. 77
4.2 Microbial Controls on Methane Fluxes from a Polygonal Tundra of
the Lena Delta, Siberia………………………………………………….. 85
4.3 Abundance, Distribution and Potential Activity of Methane
Oxidizing Bacteria in Permafrost Soils from the Lena Delta,
Siberia…………………………………………………...………………... 96
4.4 Methanogenic Activity and Biomass in Holocene Permafrost
Deposits of the Lena Delta, Siberian Arctic and its Implication for
the Global Methane Budget…………………………………………….. 105


6 Methane Cycle in Permafrost Ecosystems Contents


5 Microbial Community Structure in Permafrost Ecosystems ………..... 117
5.1 Characterization of Microbial Community Composition of a Siberian
Tundra Soil by Fluorescence in situ Hybridization............................. 117
5.2 Methane Fluxes in Permafrost Habitats of the Lena Delta: Effects
of Microbial Community Structure and Organic Matter
Quality………..…………………………………………………………… 126
5.3 Methanogenic Communities in Permafrost-affected Soils of the
Laptev Sea Coast, Siberian Arctic, Characterized by 16S rRNA
Gene Fingerprints….……….…………………………………………… 135

6 Methanogenic Archaea as Model Organisms for Life in Extreme
Habitats and Their Astrobiological Relevance…...……………………… 146
6.1 Microbial Life in Terrestrial Permafrost: Methanogenesis and
Nitrification in Gelisols as Potentials for Exobiological Processes…. 146
6.2 Simulation of Freezing Thawing Cycles in a Permafrost Microcosm
for Assessing Microbial Methane Production under Extreme
Conditions………………………………………………………………… 160
6.3 Stress Response of Methanogenic Archaea from Siberian
Permafrost Compared to Methanogens from Non-permafrost
Habitats…..…………………………………………………….…………. 167
6.4 Survival of Methanogenic Archaea from Siberian Permafrost Under
Simulated Martian Thermal Conditions.............................................. 180

7 Synthesis…...…………………….……….……………………………………. 190
7.1 Introduction…….……………………….………………………………... 190
7.2 Methane Release from Tundra Environments of the Lena Delta…... 191
7.3 Microbial Processes and Communities Involved in the Arctic
Methane Cycle……………...……….…………………......................... 198
7.4 Survival of Methanogenic Archaea under Extreme Environmental
Conditions……...……………………………………………..…..……… 204

8 Conclusions…….…………………………………………………….…...…... 210

9 References……….…………………………………………………………….. 212

Acknowledgements…………………………………………………………… 237

Appendix…………………………………………………………….………….. 238
Correspondence for the Publications under Revision………………………. 238
List of Oral and Poster Presentations………………………………………… 242

7Abstract Methane Cycle in Permafrost Ecosystems


Abstract

The