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Measurements of electrical conductivity indicate the salinity of the water. It influences the growth of the algae Prymnesium parvum. © Lena Giovanazzi
It can be assumed that renewed mass developments of the alga Prymnesium parvum in the Oder are possible under environmental conditions similar to those in summer 2022. In order to track and map future developments, extensive monitoring of water quality from a chemical and ecological perspective is necessary. Subproject 3 "Water quality and phytoplankton: documentation of spatio-temporal development" has therefore set up a network of discrete sampling sites in close co-operation with the Brandenburg State Office for the Environment (LfU). The investigations supplement the existing official measures of long-term chemical-ecological monitoring in accordance with the EU Water Framework Directive.
The parameters analysed in the sub-project include physico-chemical components of water quality such as temperature, dissolved oxygen, salinity, acidification status and nutrient ratios. The sub-project staff document selected trace elements and metals, organic trace substances and algae pigments as further parameters with significant relevance for the special investigation programme. They are also carrying out a Prymnesium screening using a qPCR-based method and developing an analysis of the toxins of Prymnesium parvum, the so-called prymnesins.
In addition to the main river, the monitoring also covers connected bodies of water, as water retention processes in these areas play a decisive role in the resilience of the river ecosystem. In addition to risk assessment, the data obtained makes it possible to document how the ecological condition of the river changes after the disaster.