Environmental impact of cold seeps in biogeochemical cycles

Methane is seeping from numerous geological sources in the Arctic Ocean associated with multiple mechanisms that elevate methane production and release. Independent of the mechanism, however, liberated methane is predominantly consumed in the water column by methanotrophic bacteria, which uses methane as a carbon and energy source during an aerobic enzymatic reaction called methane oxidation. In sedimentary fluid flow systems such as cold seeps or hydrothermal vents, the amount of methane release and subsequent oxidation would be substantial, which may trigger other ecosystem processes such as bacterial growth, heterotrophic consumption, and mechanisms that alter organic matter composition in the water column.

I investigate the impact of methane on water column ecosystems and biogeochemistry using high-definition analytical instruments, microbial microcosms, and high-resolution water column characterization techniques.

There are two primary sources of methane in the Arctic Ocean. Cold seeps and hydrothermal vents. Cold seeps are the point sources of hydrocarbon gases in marine sediments that originates from dissociating methane hydrates and gas reservoirs accumulated in pore spaces of sediments. Methane hydrates are the cage-like structures that trap methane between water molecules and are stable only under a specific temperature and pressure range. Methane is a source of carbon and energy for many different types of organisms that thrive nearby the cold seeps and hydrothermal vents and form communities and large populations.

If some portion of the energy gained from methane oxidation is transferred to the organic matter synthesis and eventually alters the DOM composition in methane-rich marine environments.

In the areas where the methane flux is substantial, like cold seeps and hydrothermal vents this mechanism may trigger other water column mechanisms and influence primary production and respiration cycles, microbial structure, and metabolic activities that even change the whole ecosystem functioning

I use CTD and the rosette system for water sampling and sensor-based profiling of the water column to work in active cold seep sites

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