Deutsch Intern
Chair of Geomorphology

Anthropogenic signatures in reservoir sediments: the past century (AReS)

Summary

Humans have exerted a strong influence on landscapes for millennia. However, since the onset of the industrialisation and especially since the mid-20th century, this influence has intensified markedly. In the Anthropocene, humans have become the dominant driver of landscape changes in many regions of the world. This is clearly reflected in their impact on the sediment cycle. While more intensive agriculture, deforestation, and mining have led to increased sediment transport in rivers, the construction of reservoirs results in a sediment deficit downstream. Owing to their high accumulation rates and undisturbed sedimentation conditions, reservoirs constitute an excellent archive of landscape history. Many pollutants released by human activities, such as heavy metals, plastics, or persistent organic pollutants, are stored in these sediments.

Building on the predecessor project 115 Years of Sedimentation in the Urft Reservoir, the project AReS – Anthropogenic signatures in reservoir sediments: the past century (AReS) aims to determine sedimentation rates and pollutant loads in five reservoirs in the northern Eifel and to identify the associated causes within their catchment areas. This will also contribute to a better understanding of how landscapes respond to climate change. The DFG-founded project will start in April 2026.

 

To assess pollutant inputs, multiple sediment cores will be collected from the reservoirs. These will be analysed for their sedimentological and geochemical composition. Owing to the long mining history of the northern Eifel, the focus is on heavy metal concentrations. One key aspect of the research is a comparison between reservoirs whose catchments are intensively settled by humans and those with more natural, largely forested catchments. Previous investigations of reservoir sediments in the Eifel have shown a pronounced decline in pollutant levels over the past 40 years. However, it remains unresolved whether this represents a local or a regional signal.

Another major focus of the project is the quantification of sediment deposits from individual flood events. So far, it is completely unclear how much sediment is delivered to the reservoirs during such events. To address this, selected reservoir beds will be surveyed regularly using high-resolution terrestrial LiDAR. In addition, the flood sediments will be examined for their composition. The goal is to use these signatures to identify past flood events within the reservoir sediment record as well.

Team