Find out more in our free public lectures on Sylt - for example in a lecture on 16 July 2024 by Andreas Waser or on 20 August 2024 by Sabine Horn.
The Wadden Sea Ecosystem
The coastal area of the south-eastern North Sea, including the Wadden Sea, is a highly productive system with diverse interactions between the organisms living here. In this coastal food web, each species plays an important role in the functions of the ecosystem as a whole. Natural, but above all man-made influences have an impact on individual species, communities and habitats. This results in changes, whereby even an initially small impact can have a major effect on the entire ecosystem.
Currently, the central question is how climate change and increasing human use influence the structure and functions of our North Sea coast and to what extent the organisms can adapt to the changes. There are also often factors that interact to cause effects that cannot be predicted.
The temporal, spatial and evolutionary dynamics of populations in coastal ecosystems are characterized by diverse interspecific interactions such as predation or parasitism. It is important to understand these natural processes in general in order to be able to assess how human influence changes them. To this end, we combine observational, experimental and molecular biological approaches to explain changes in the occurrence of species and their population structure, as well as to identify adaptation strategies of organisms to a changing environment. One focus is on the effects of introduced species that make the leap from distant coasts to our native areas through international shipping and aquaculture activities and successfully colonize them here. The Pacific oyster plays a special role here. This species, which has been introduced since the 1980s, forms dense reefs on the seabed in the mid-tidal area up to the permanently flooded areas of the Wadden Sea. Here it has transformed previously existing native mussel beds into mixed reefs of mussels and oysters, creating a completely new type of habitat with an impact on the existing biocoenosis. The oysters did not come alone, but brought with them other associated species, including parasites and diseases, which now also affect native species. The resulting changes in the biodiversity of the Wadden Sea are being investigated using modern DNA technology, from the genetic level to microbial, plankton and benthic communities. In addition, the commercially used North Sea shrimp and the three-spined stickleback play an important role as model species. In particular, sticklebacks can be used to identify how environmental changes are reflected in the genetics of organisms and how they adapt at the molecular level. Our investigations include controlled laboratory experiments, the use of our mesocosm facility, in which future climate scenarios and their effects on the Wadden Sea are simulated, as well as extensive studies in the field.
The results of the individual studies are incorporated into a holistic food web model. This helps to understand the Wadden Sea as a whole and to comprehend the consequences of changes for the Wadden Sea as well as to predict future developments.
Analyzing the effects of human activity on our marine ecosystems makes it possible to find new and innovative forms of marine use. These include, for example, gentle tourism, ecosystem-compatible fishing and the sustainable expansion of alternative energy production on the high seas.
This requires three important building blocks: 1) coordinated management of all human activities in the coastal seas; 2) the development of new marine “eco-structures” and ecology-promoting and sustainable infrastructures; and 3) the establishment of new scientific observation systems that can be used to monitor biodiversity and the state of coastal ecosystems and assess the impact of human intervention.
AWI experts
Marine ecologist Dr Christian Buschbaum, expert on coastal research
Biologist Dr Lisa Shama, expert on the topic of coastal research
Fisheries scientist Dr Merten Saathoff, expert on the subject of population dynamics
Marine biologist Dr Annika Cornelius, expert on community and evolutionary ecology
Coastal and shelf researcher Dr Sabine Horn, expert on the topic of ecological network analysis
Coralie Broquard
