The methane cycle in estuaries

The global methane (CH4) budget is becoming an increasingly important component for managing realistic pathways to mitigate climate change. The most important source of uncertainty on the methane budget is attributable to emissions from wetland and other inland waters (Saunois et al 2016). Therefore, our aim is to contribute ground data on methane concentrations in different aquatic environments.

Estuaries are thought to act as efficient filter of different forms of riverine organic carbon before it enters the coastal seas. However, during hydrological extremes (flooding or droughts) the residence time of the riverine water will be changed with until now unknown effects on the filtering capacity. In the framework of MOSES and in cooperation with other research institutes (HZG, Geomar, UFZ) we therefore intend to monitor the distribution of CH4 and CO2 in high spatial and temporal resolution in the Elbe estuary.

Another hot spot of unknown magnitude is the rapid thawing of permafrost soils and sediments in the arctic region. In In the framework of MOSES and in cooperation with other research institutes (AWI-Periglacial Research, GFZ, Geomar) we plan to assess the influence of rapidly thawing permafrost on the distribution of methane in the aquatic environment. Especially the winter situation, the methane cycle in and under ice is mostly unknown, albeit the predominant situation in the arctic.

Another aspect of our methane-related reseach, is the biogeochemistry of kelp degradation on beaches. In cooperation with the MPI-Bremen, we investigate the release of different greenhouse gases (CO, CO2, CH4 and N2O), and their influence on the geochemistry and microbiology of the intertidal sands

Association in PACES: Topic 1 WP5 & Topic 2 WP1