I collected my first research experience in 1984 as a field worker on a reconstructed ancient rainwater harvesting farm. The system was studied from different disciplinary view-angles, including archeology, agronomy, geology, hydrology, plant ecology, and meteorology. The operating principles of the farm could only be fully understood by integrating the findings of these disciplines. I am interested in integrated studies since then. I actively worked in different disciplines, encompassing irrigation engineering and scheduling, limnology, plant ecology, agrometeorology, international agriculture, forest ecology and agroecology. I apply modelling techniques to formulate research hypotheses and to understand functional aspects of agroecological systems. This includes assessing options for model fusion, scaling studies, and pattern analyses. Modelling human and hydrological effects on the agroecology of East-African wetlands, understanding the evolution of soil-vegetation-atmosphere patterns in the Rur valley of Germany, and quantifying hybrid performance in rapeseed breeding are my current research activities.
Analyzing the effects of absence or presence of water in agroecological systems is a major interest. I worked in irrigation practice and engineering, studied plant-water relations in different contexts, conducted energy-balance studies, analyzed and modelled light-distribution patterns in forest streams, assessed the microclimate and heat fluxes in crops and forests, and determined plant and tree water-uptake patterns with different thermoelectric methods. I am currently studying the effects of spatio-temporal soil-moisture patterns on the formation of crop ecophysiological and vegetation patterns in Germany and East-Africa. Another important activity is the parameterization and coupling of water transport and crop growth models to better understand interrelations between hydraulic plant architecture and growth. The aim of this activity is to improve the plant functional type characterization in land-surface models.
Developing a decision making tool to relate science-based modelling to practical political decision making is a new activity which has recently evolved in my work within the collaborative research "Wetlands in East Africa: Reconciling future food production with environmental protection".