Preliminary Geochemical and Lipid Biomarker Results from Lake Stechlin, Northeastern Germany

Northeastern (NE) Germany is characterized by continental climate conditions and is modelled to become even drier due to global climate change. This will aggravate the ecological and socio-economic consequences observed already over the last few years, such as intense droughts and forest fires. Detailed knowledge of regional past climate and environmental changes, as well as their potential supra-regional drivers, is urgently needed to understand climate-environmental interactions and to better anticipate future changes.

Here we present preliminary results from a 95 cm long sediment core from Lake Stechlin that spans ~5,000 years.  At ~50 cm depth, a distinct lead maximum is likely associated with medieval industries. At the same time, organic carbon drops, and increasing clay and potassium contents indicate mineral input, likely due to deforestation and massive erosion. The higher average chain length of the n-alkanes documents more input of grass- rather than tree-derived leaf waxes. Concentrations of n-alkanes are high throughout the record and allow for δ²H measurements on terrestrial and aquatic compounds. These are currently in progress to investigate past changes in lake water evaporation and thus drought. Moreover, we will present polycyclic aromatic hydrocarbons as paleofire and erosion proxies to further explore anthropogenic impacts.