WP4 Integrated modelling

WP-leader: Peter Engesgaard

There is a need for the development of integrated hydrological-nitrate models that can support management and legislative demands when trying to introduce a spatially differentiated regulation of nitrogen. Such a model must represent the dominant flow, transport, and biogeochemical processes affecting nitrate from the agricultural-drained soils, through the geological-reactive, but heterogeneous system, before finally exiting to streams through biogeochemical active lowland riparian zones. Although advancements have been achieved in recent years, the present model approaches do still have problems with inadequate representation of dominant processes and their spatial heterogeneity. Especially processes such as drainage and local flow paths and removal of nitrate in riparian lowlands are not well described in the catchment scale models. There is therefore a research need to formulate adequately upscaling approaches for upscaling the local-scale process knowledge obtained in field studies and detailed local-scale modelling to catchments scale models. In TReNDS scientists will work with the following hypothesis:

Hypothesis G: Results from the field studies and the associated investigative hydrological modelling can be upscaled and integrated in catchment scale models by developing new concepts to represent the dynamics of drains and riparian lowlands, which will improve model reliability and the resolution at which model results can be utilised for differentiated regulation.