Microbial grazers shall be investigated in combination with microorganisms (in single or joint projects) in order to study trophic interactions and fluxes in (simple) food webs. In order to keep an experimental focus and manageable complexity for ecosystem modelling this research is focused to the following groups: Protozoa and nematodes as major bacterial grazers, and Collembola as dominant soil fungivores. Limiting experiments on trophic networks to two trophic levels will increase manageability of experiments and facilitate assignment of processes to specific taxa. The interaction strength, i.e. strong versus weak C flow, across trophic connections thereby determines network stability as well as C dynamics (Neutel et al., 2002; Neutel et al., 2007) and can be reliably detected by use of stable isotope labels.
References
Neutel, A.M., Heesterbeek, J.A.P., De Ruiter, P.C., 2002. Stability in real food webs: Weak links in long loops. Science 296(5570), 1120-1123.
Neutel, A.M., Heesterbeek, J.A.P., Van De Koppel, J., Hoenderboom, G., Vos, A., Kaldeway, C., Berendse, F., De Ruiter, P.C., 2007. Reconciling complexity with stability in naturally assembling food webs. Nature 449(7162), 599-602.