I am interested in the compound turnover in the environment catalysed by microorganisms. Major focus is not on the organisms itself but on the turnover rates and the system properties. Current research topics are: Bioremediation processes • Microbial degradation potentials and in situ activity Metabolic flow in environmental systems C and N turnover in soil, genesis of soil organic matter Chemical and microbial ecology in soils, sediments, and groundwater Isotope tools and tracer compounds