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Team members of the subproject take water samples from the Oder, which are then analysed in the laboratory for DNA traces of organisms. © Astrid Scheuermann
eDNA or environmental DNA consists of the DNA of the smallest organisms and the DNA traces that larger organisms leave behind in the environment. With the help of eDNA monitoring, water samples can be used to trace which groups of organisms are currently or have been present at a location in a body of water. Sub-project 9 "eDNA-based multitrophic monitoring of toxin-sensitive aquatic organisms" uses this method to record the consequences of the Oder disaster for all trophic levels: from bacteria and fungi to plankton and animals in the sediments, in the river water and in the floodplains. The scientists are thus gaining insights into how the Oder ecosystem as a whole is recovering. For example, they can also detect at an early stage if an invasive species – i.e. an alien species that can jeopardise the ecosystem – spreads rapidly as a result of the disaster-related losses of native species.
Compared to conventional methods for detecting the groups of organisms present in a body of water, eDNA monitoring allows, among other things, a significantly larger number of groups of organisms to be detected in a single water sample and samples to be analysed much more efficiently. The sub-project therefore also contributes to research into future early warning systems for algal blooms similar to the devastating Prymnesium bloom in the Oder River in the summer of 2022.
Compared to conventional methods for detecting the groups of organisms present in a body of water, eDNA monitoring allows, among other things, a significantly larger number of groups of organisms to be detected in a single water sample and samples to be analysed much more efficiently. The sub-project therefore also contributes to research into future early warning systems for algal blooms similar to the devastating Prymnesium bloom in the Oder River in the summer of 2022.
The scientists in the subproject are collaborating with the GeDNA project. For quality control, samples will be analysed both at the Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB) and at the University of Duisburg-Essen.