Freshwater systems are some of the ecosystems most intensively used and severely impaired by humans. Human-dominated aquatic systems have substantial socio-economic importance for drinking water, flood protection, hydropower, irrigation, navigation, fisheries, and recreation. These uses are socially accepted, politically welcome, and often irreversible. Thus, complex social-ecological systems have been created that are of central importance for both ecosystem services and aquatic biodiversity.

Understanding the direct and indirect effects, impacts, and feedback mechanisms between humans and ecosystems provides the scientific basis to derive integrative management approaches. Major gaps in scientific knowledge exist in understanding the effects of multiple pressures on biota at different temporal and spatial scales. A particular scientific challenge is gaining understanding of the structure and function of coupled social-ecological aquatic ecosystems and adjacent terrestrial habitats in order to identify key structures and processes in impaired aquatic ecosystems and to improve their ecological potential.

Current research projects include the analyses of recreational fisheries management as a coupled social-ecological system (Adaptfish, Besatzfisch), the development of reliable ecological assessment tools (WISER), adaptive management strategies to respond to climate change effects in aquatic systems (INKA BB), light pollution (Loss of the Night, Lichtimissionen im öffentlichen Raum), the rehabilitation of sturgeon as charismatic umbrella species (Wiedereinbürgerung des Störs in Nord- und Ostsee), and understanding biotic responses to hydromorphological changes (FORECASTER, IMPACT, Domesticated Ecosystems), and nutrient emissions and transformations (GLOWA-Elbe-III, RADOST, AMBER).