Within the DFG-Research group 'Competitive mechanisms of water and N partitioning in beech-dominated deciduous forests' the IMK-IFU has its focus on the further development and validation of existing process-orientated, biogeochemical models (here MOBILE, with PSIM used as Plant Module and DNDC as Soil Module) in order to predict inter- and intra-specific competition between plant roots, mycorrhizal fungi and bacteria with regard to N- (differentiated for ammonium and nitrate) and water uptake. As a new feature we incorporated a new mycorrhiza module, describing its growth, death and activity, which allows also for nutrient exchange between mycorrhizal fungi and plant roots. Furthermore, C- and N-allocation in the plant and simulation of soil depth dependent root growth in dependency of water- and nutrient availability has been re-parametrised based on experimental and theoretical constrains.

After model development and validation with field and laboratory data, the model will be used to predict N- and C- turnover and storage in forest ecosystems, stands dynamic and biosphere-atmosphere exchange of C- and N- compounds under scenarios of future environmental change on local and regional scales.

Contacts: Butterbach-Bahl, Rüder Grote,