1. Department of Community and Ecosystem Ecology Leibniz Institute of Freshwater Ecology and Inland Fisheries 12587 Berlin Germany
2. Department of Plankton and Microbial Ecology Leibniz Institute of Freshwater Ecology and Inland Fisheries Stechlin Germany
3. Institute for Biochemistry and Biology, Potsdam University Potsdam Germany
4. Department F.‐A. Forel for Environment and Aquatic Sciences, Faculty of Science University of Geneva Geneva Switzerland
5. Institute of Earth Sciences, Heidelberg University Heidelberg Germany
6. Heidelberg Center for the Environment (HCE), Heidelberg University Heidelberg Germany