Aarhus University Seal / Aarhus Universitets segl

Akvatisk biologi - gammel side

Aquatic ecosystems are of great importance as a habitat for a wide variety of organisms. The Section conduct research and teach in processes, structures and pathways in most aquatic and wet ecosystems. Geographically, we cover aquatic ecosystems in temperate, tropical and arctic regions, and we work with both basic and applied science.

Freshwater areas

Our research in freshwater areas is all about the life found in fresh water. We work with both physical and chemical structures, plants, wildlife and microbial populations as well as interactions among these components, and the management of freshwater resources. In particular, we focus on invasive plants and their effects on biodiversity, biological and physical processes affecting carbon and nutrient cycling in wetlands and streams, and controlling factors for abundance and distribution of aquatic plant communities.


Estuaries are the transition between freshwater and seawater. Only relatively few plants and animals have adapted to life in an estuary. In turn, the number of individuals is high in estuaries because freshwater adds large quantities of nutrients resulting in a higher primary production. In the Wadden Sea, where the tide dominates, invasive species such as Pacific oysters and American razor shells are spreading. We examine how the species affect the ecosystem, and we work with parasites in marine organisms and the effects of these at individual and population level.

The Ocean

We study the pathways and volumes of material flowing into and out of an ocean. How large quantities of atmospheric CO2 can the oceans absorb and which mechanisms are controlling this? How large quantities of phytoplankton are produced, and how does it affect the optical conditions in the oceans in space and time? We also zoom in on the ecology of marine organisms and work on e.g. isotope and growth analysis of fish otoliths and the relationships between environmental forcing and ocean productivity.


Wetlands are among the most productive ecosystems in the world. Wetlands sequester carbon from the atmosphere and form peat, but at the same time the reducing conditions in wetland soils results in significant emission of methane. We study biogeochemical processes in wetlands, including nutrient transformations and greenhouse gas emission. We also study constructed wetlands (CWs), also known as treatment wetlands, which are engineered systems designed and constructed to treat various types of polluted water.

Plant Ecophysiology

Plants are fascinating organisms that are capable of acclimatizing and adapting to an enormous range of environmental conditions. Our research focuses on the physiological, biochemical and morphological mechanisms that plants use to cope with stresses, suboptimal conditions and climatic changes. The response strategies can vary largely between, but also within, plant species, and therefore we investigate, which inherent plant traits are responsible for those different reactions.