Coastal Peatlands are important carbon sinks and can have a significant impact on mitigating climate change. In recent years, efforts to rewet previously drained peatlands have therefore increased. However, the impact of salinity on the success of rewetting measures is to date not well known. The aim of this study was thus to investigate changes in biogeochemistry and carbon release under two different salinity regimes over 3 months. Samples for this study were taken from a coastal peatland at the German Baltic Sea coast near Drammendorf. The area is situated in the south-west of the island of Rügen, Germany. It was drained for grassland use in the 1970s and was rewetted three years ago, in late 2019, by removing the former dike and flooding it with brackish water from the nearby bay, Kubitzer Bodden. Peat samples representative of 3 depths from the coastal peatland were incubated as slurries under anoxic conditions at 15 °C.  First results of this study, including production of CH₄ and CO₂ over time, pH values, values of δ¹³C-CH₄ and δ¹³C-CO_2, iron speciation, acetate, SO₄, nutrients, and DOC, will be presented.

Primary Presenter: Nina Schulze, University of Rostock (nina.schulze@uni-rostock.de)

Authors:

Nina Schulze, Landscape Ecology, Faculty of Agricultural and Environmental Sciences, University of Rostock  (nina.schulze@uni-rostock.de)

Sara Anthony, Landscape Ecology, Faculty of Agricultural and Environmental Sciences, University of Rostock  (sara.anthony@uni-rostock.de)

Klaus-Holger Knorr, Ecohydrology and Biogeochemistry Research Group, Institute of Landscape Ecology, University of Münster  (kh.knorr@uni-muenster.de)

Susanne Liebner, GFZ German Research Center for Geosciences, Helmholtz Centre Potsdam, Section Geomicrobiology; Institute of Biochemistry and Biology, University of Potsdam  (sliebner@gfz-potsdam.de)

Gerald Jurasinski, Landscape Ecology, Faculty of Agricultural and Environmental Sciences, University of Rostock; Peatland Science, Institute of Botany and Landscape Ecology, University of Greifswald; Maritime Systems, Interdisciplinary Faculty, University of Rostock  (gerald.jurasinski@uni-greifswald.de)