Dissent in the Sediment? – Lake sediments as archives of short- and long-range impact of anthropogenic activities in northeastern Germany

Abstract

The suitability of lake sediment cores to reconstruct past inputs, regional pollution, and usage patterns of pesticides has been shown previously. Until now, no such data exist for lakes in eastern Germany. Therefore, ten sediment cores (length 1 m) of ten lakes in eastern Germany, the territory of the former German Democratic Republic (GDR), were collected and cut into 5-10 mm layers. In each layer, concentrations of trace elements (TEs) As, Cd, Cr, Cu, Ni, Pb, S, Zn, as well as of organochlorine pesticides (OCPs) were analyzed. A miniaturized solid-liquid extraction technique in conjunction with headspace solid-phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS) was used for the latter. Of OCPs, only transformation products of dichlorodiphenyltrichloroethane (DDT) were found. Congener ratios indicate a mainly aerial input. In the lakes’ profiles, several regional features and also responses to national policies and measures are visible. Dichlorodiphenyldichloroethane (DDD) concentrations reflect the history of DDT use in the GDR. TEs show a uniform progression over time. They follow a trans-regional pattern and are indicative of activity and policy making in West Germany before 1990 instead of those in the GDR. Lake sediments proved to be suitable to archive short- and long-range impacts of anthropogenic activity. Our data can be used to complement and validate other forms of environmental pollution long-term monitoring and check for the efficiency of pollution counter measures in the past.

Driver–response relationships in a large shallow lake since the Anthropocene: Short‐term abrupt perturbations versus long‐term sustainable pressures

“…Research on lake sediment proxies has highlighted the timely or lagged recording of catchment natural‐dominated abrupt events (such as extreme floods, earthquakes, and fires) and their quantitative reconstruction (Gilli et al., 2013; Martins et al., 2023). Large‐scale events caused by human activities, officially documented as dam construction and afforestation, have frequently been described via sediment records (Dearing et al., 2012; Simon et al., 2023). The timely or lagged recording of events has led to uncertainty regarding the magnitude of typical anthropogenic events recorded in lake sediments, particularly during the Anthropocene, when human activity intensified.…”