The effects of the Oder disaster on the river's floodplains have so far been the subject of little research. © Shutterstock
In the event of toxin waves, such as those caused by the algae Prymnesium parvum in the salt-polluted Oder River in the summer of 2022, the floodplains and their tributaries provide an important refuge for organisms threatened by the toxin. The dynamic floodplains are also characterised by a high level of biodiversity. However, data on the species communities (biocoenosis) in the Oder floodplain have not yet been collected as standard in monitoring programmes. The extent to which organisms in the Oder floodplain suffered from the man-made disaster is therefore currently impossible to assess.
Sub-project 12a "Biocoenotic floodplain assessment" collects basic data that can be used to assess the development of floodplain biocoenoses in the future. The researchers from the University of Duisburg-Essen and their team are collecting data on habitat features and on five groups of organisms in each of five floodplain sections: higher plants, molluscs, ground beetles, amphibians and birds. They used the method "Biocoenotic success monitoring of renaturalisation measures on river banks and in floodplains" (Januschke et al. 2023, in German). The assessment procedure is based on a comparison of sections with different degrees of naturalness.
In sum, a comprehensive picture of the floodplain biocoenoses will emerge. Differences between individual sites allow conclusions to be drawn about the impairment of the biocoenoses and the potential for improvement. Based on the data collected, measures for floodplain development and for increasing the resilience of the floodplain can be developed.
