- 1Ecohydrology and Biogeochemistry Group, Institute of Landscape Ecology, University of Münster, Münster, Germany (sara.anthony@uni-muenster.de)
- 2Peatland Science, Institute of Botany and Landscape Ecology, University of Greifswald, Greifswald, Germany
- 3Landscape Ecology, Faculty of Agricultural and Environmental Sciences, University of Rostock, Rostock, Germany
- 4Catchment Science and Environmental Management, Department of Ecoscience, Aarhus University, Aarhus, Denmark
- 5Department of Ecohydrology and Biogeochemistry, Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Germany
- 6Maritime Systems, Interdisciplinary Faculty, University of Rostock, Rostock, Germany
- 7GFZ Helmholtz Centre for Geosciences, Section Geomicrobiology, Telegrafenberg, Potsdam, Germany
- 8Institute of Biochemistry and Biology, University of Potsdam, Potsdam, Germany
Coastal peatlands are believed to exert a substantial influence in mitigating climate change and many of these valuable ecosystems have been drained for agriculture, becoming significant carbon sources. The impact of draining and re-wetting a peatland on the microbial community is of great importance for our comprehension of carbon cycling. The balance between methane producing (methanogenic) and methane oxidizing (methanotrophic) microbial communities, and the interaction with other nutrient cycling microbes is especially important. Multiple recent studies have found methanotroph abundance to be smaller than methanogen abundance post rewetting, potentially leading to prolonged high methane emissions. Anaerobic methanotrophs (ANME) are especially known to be slow growing and it remains unknown if they can establish in rewetted coastal fens at all. The former coastal peat-forming brackish marsh Drammendorf, located in NE Germany, was drained in the 1970s to be used as grassland. In 2019 it was rewetted with brackish water from the adjacent Kubitzer lagoon system. To track how the microbial community adapted to new conditions, samples for 16S rRNA and metagenomic sequencing were collected at three timepoints: in 2019 before the rewetting; in 2020 6-9 months after rewetting; and again in 2022, approximately 2.5 years post rewetting. The first results reveal an increase in methanogen abundance and diversity that outpaces that of methanotrophs, as well as a strong sulfur and iron cycling community. In addition, sulfate-driven anaerobic methanotrophs (ANME-2a/2b) appear to be establishing a presence in the subsurface 2.5 years after rewetting, which has never before been observed in a rewetted peatland. The establishment of these specialized methanotrophs has potential implications for coastal methane emissions, especially as global climate change induces progressive sea level rise. Understanding the reasons why they establish in certain new peatland habitats may lead to the ability to support establishment in other environments.
How to cite: Anthony, S. E., Gukekunst, C., Knorr, K.-H., Zak, D. H., Jurasinski, G., and Liebner, S.: Establishment of sulfate-driven anaerobic methanotrophs in a rewetted coastal peatland, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-5712, https://doi.org/10.5194/egusphere-egu25-5712, 2025.
