Spatially distributed lateral nitrate transport at the catchment scale.

In river catchments, N transformation and storage processes during lateral transport are important in controlling N loads of surface waters. There is a lack of approaches which capture lateral flows and associated N transformation in a spatially distributed way. The aim of this paper is to develop a new conceptual N transport and transformation model which simulates the lateral nitrate transport in subsurface flow from the source area to the receiving water body.

Impact of selected agricultural management options on the reduction of nitrogen loads in three representative meso scale catchments in Central Germany.

Nitrogen inputs into surface waters from diffuse sources are still unduly high and the assessment of mitigation measures is associated with large uncertainties. The objective of this paper is to investigate selected agricultural management scenarios on nitrogen loads and to assess the impact of differing catchment characteristics in central Germany. A new modelling approach, which simulates spatially distributed N-transport and transformation processes in soil and groundwater, was applied to three meso scale catchments with strongly deviating climate, soil and topography conditions.