Influence of xenobiotics and climatic change on essential fatty acid synthesis of microalgae and zooplankton in fishponds of Lower Austria

In aquatic systems, essential biomolecules such as fatty acids are produced by phytoplankton and then transferred through the food web to zooplankton, fish, and finally humans. Environmental factors have been shown to influence the fatty acid metabolism of microalgae. Thus, temperature rise due to climate change as well as the introduction of xenobiotics such as pesticides can have severe consequences for aquatic organisms. This topic is highly relevant for the Lower Austrian region Waldviertel with its many carp ponds. Therefore, the main aim of this research project, which will be conducted by BEST GmbH, WasserCluster Lunz GmbH, and BOKU, is to investigate the consequences of temperature increase and exposure to pesticides for the dietary value of organisms in carp ponds in Waldviertel. Therefore, samples from such ponds will be analyzed to find xenobiotics, microalgae and zooplankton species present in these ecosystems. In subsequent lab trials, microalgae will be exposed to increased temperature and/or pesticides. Zooplankton will be fed with microalgae that have were grown under these conditions. The fatty acid content and profile of microalgae and zooplankton biomass will then be analyzed. Thus, the effect of temperature increase and pesticide pollution and the combined effect of both on organisms in carp ponds in Waldviertel will be investigated. The project will help understand the interactions between different organisms in the food web and how the organisms’ dietary values are influenced by pesticides and increased temperature. The results will be presented to stakeholders and to a scientific audience at workshops, conferences, and via publications. During this project, young researchers will be supported and networks and cooperations between three independent research institutions in Lower Austria will be strengthened. Overall, the results gained in this project will help sustain the high ecological and economical value of carp ponds in Lower Austria.