Late Pleistocene to Holocene climate variations and anthropogenic changes in the North German Plain inferred from lake and peat sediments from Schweriner See

• Applicant: Professor Dr. Torsten Haberzettl
• Subject Area: Physical Geography
• Term: since 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 451683760

North Germany has been subjected to constant hydrological changes since the Last Glacial Maximum, which has been shown in an up to now very limited number of studies. An in-depth understanding of long-term hydrological dynamics in the past is important to respond to recent and future challenges regarding the hydrologic balance in Northeast Germany. Today it is characterized by lowering lake and groundwater levels. However, an understanding of the dynamics is still far from being complete. Although the anthropogenic influence on lacustrine systems has always been high since the Neolithic, paleohydrological investigations differentiating between Holocene climatic and anthropogenic influences using the same (geo)archive are largely missing. In order to tackle these deficiencies, we propose a sediment core transect study through Schweriner See. The Schweriner See is especially suited for these kinds of investigations as it is one of the largest lakes in North Germany (minimizing the risk of interpreting local events as supra-regional climate signal). Furthermore, it is located within the transitional zone from maritime to subcontinental climate, which makes it very susceptible to hydrological variations. Geophysical investigations (parametric echosounder, side scan sonar) will be used to locate the most suitable coring positions. Sediment cores will be parallelized and investigated with a multi-method dating approach (AMS 14C and paleomagnetic secular variation stratigraphy) as a new concept for NE-Germany. This is followed by a multi-proxy approach (sedimentology, geochemistry, diatom analysis and pollen) for a hydrological reconstruction. To achieve a quantitative continuous paleohydrological reconstruction, semi-quantitative, continuous, high-resolution results from a distal sediment core will be linked with quantitative data from littoral and onshore sediment sequences which directly mirror lake level variations in their stratigraphies. In addition to the hydrological reconstructions, we aim to investigate how the Schweriner See system reacted on lake level variations (e.g., potential eutrophication tendencies) and how it responded to lake external forcings (e.g., temperature, insolation). This will be essential in order to be able to predict potential future scenarios under similar boundary conditions, which can be assumed against the background of Global Change.

• DFG Programme: Research Grants