- Departments
- Department of Biogeochemistry
- Greenhouse Gases Research Group
- People
- Judith van der Giessen
Judith van der Giessen
MPI for Marine Microbiology
Celsiusstr. 1
D-28359 Bremen
Germany
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Room: |
3129 |
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Phone: |
Research Interests
I study the role of microorganisms in methane cycling in freshwater lakes and coastal systems. My research sites include stratified lakes in Switzerland and seagrass meadows in the Mediterranean Sea:
- In large lakes, the majority of the produced methane by oxygen sensitive methanogens in sediments is depleted before it reaches the surface waters. Nonetheless, methane super-saturation has been reported to occur in oxic surface waters of freshwater lakes. I study which microbial processes contribute to this so called ‘methane paradox’ in lakes.
- Seagrass ecosystems store carbon in the form of peat deposits. However, due to the high organic matter content and anoxic conditions in the underlying sediment, they are also systems in which methane production by methanogens readily occurs. I am interested how microorganisms associated with the seagrasses as well as the overlaying water column affect the methane cycling in seagrass meadows.
In my doctoral study, I perform stable isotope incubation experiments followed by isotope-ratio mass spectrometry analyses. These will be combined with biogeochemical in situ profiles (e.g. nutrients and gases) and molecular methods (e.g. DNA/RNA sequencing and cell visualization).