Current Projects
Several projects aim at increasing or knowledge of food web regulation within two focal habitat types, the pelagic zone and the macropohyte beds.
Pelagic Zone
Experimental work analyses clonal diversity in Daphnia ephippia production and the role of food quality in the decision of Daphnia to reproduce sexually versus parthenogenetically (PhD Thesis by Ully Koch)
In two projects we analyse the response of plankton to climate variablity and trophic changes (eu- and oligotrophication) using long-term time series. Hanno Seebens (PhD thesis) analyses the dynamics of a copepod community and investigates the role of copepod life cycles (diapause strategies) and intraguild predation for population and copepod community response to environmental change. Marc Jochimsen (PhD thesis) analyses the response of the phytoplankton community (individual species, biodiversity, and functional groups) to environmental change using the outstanding 40 years data set of Lake Constance phytoplankton. The special interest of this project is to combine the analysis of phytoplankton functional groups with analyses of biodiversity dynamics in order to address the functional consequences of biodiversity.
Kristine Schalau and Onur Kerimoglu use simulation models to study plankton dynamics. Kristine focusses in detail on climate influences on Daphnia algal interactions by using a stage-structured Daphnia population model (PhD thesis, co-supervisor: Frank Peeters), whereas Onur uses a coupled hydrodynamical-biological model to study the influence of climate variability on spring plankton succession (PhD thesis, co-supervisor: Frank Peeters).
Macrophyte beds
Experimental work in mesocosms studies the interactions between fish (sticklebacks), Acentria ephemerella, a key herbivore in the macrophyte beds of Lake Constance, and the macrophyte species Potamogeton perfoliatus. Research focusses on direct and trait-mediated effects of predation (herbivory) on Acentria (Potamogteon), as well as on the anti-predator and anti-herbivore strategies of Acentria and Potamogteon, respectively (PhD thesis Oliver Miler).
Yoann LeBagousse-Pinguet (PhD thesis) recently started to continue this work and focusses additionally on the effects of Acentria on interactions (competition versus facilitation) between plant species.
The Diploma thesis of Stefanie Eschenbaecher focusses on the effects of Acentria density on individual growth, male competition and wing dimorphism of Acentria.