Human-environment interactions in the Anthropocene – a case study on reservoir sediments in Central Europe

Over the last century, the anthropogenic impact on the landscape has increased significantly. In many regions, humans have become the most influential geomorphological factor. This has led to increased sediment fluxes, heavy metal contamination and plastic waste. As a result, humans are altering both the sediment budget and composition. Anthropogenic climate change is expected to further increase sediment fluxes. However, quantifying human-environment interactions remains a critical task.

To investigate such human influence on a central European landscape, reservoir sediments were analysed. The selected reservoir, built in 1905 and still in use, was completely drained in autumn 2020. This provided a rare opportunity to reconstruct the accumulated sediment volume and to analyse sediment deposition. High-resolution digital surface models were generated photogrammetrically and from historical topographic maps. In addition, 24 cores were retrieved and analysed for grain size, geochemical composition and microplastic content. Caesium-137 was used to date the sediments.

In contrast to many other regions, sediment accumulation in the reservoir has declined in recent decades. Similarly, the levels of heavy metals, particularly copper, lead and zinc, have decreased since the 1970s. These trends can be attributed to environmental legislation and the closure of a metal processing plant upstream. The Anthropocene imprint is thus highly spatially variable and influenced by effective government environmental protection.