Sediment and water column parameters measured at Boknis Eck (SW Baltic Sea) on a seasonal basis from 2013-2014

Water column parameters like oxygen, temperature and salinity together with porewater geochemistry and benthic methanogenesis rates were determined in the sampling area 'Boknis Eck' quarterly from March 2013 to September 2014, to investigate the effect of seasonal environmental changes on the rate and distribution of surface methanogenesis and to estimate its potential contribution to benthic methane emissions.

Water column parameters where determined via CTD (temperature, salinity, pressure), as well as gas chromatography (methane) and fluorometric methods (chlorophyll a). For porewater and sediment geochemistry various method were used including photometry (sulfide), ion chromatography (sulfate), N/C Analysis (DIC), Carbo-Elba element analysis (POC, C/N), gas chromatography (methane). Sediment net methanogenesis rates were determined via the methane increase (measured with gas chromatography) over time in sediment slurry batch incubations.