ABSTRACT
Introduction............................................................................................................223 Investigation Area ..................................................................................................225 Objectives...............................................................................................................227 Database.................................................................................................................227 Model Description .................................................................................................228 Results....................................................................................................................229 Scenarios ................................................................................................................231 Discussion ..............................................................................................................234 Conclusions............................................................................................................236 Acknowledgments..................................................................................................236 References..............................................................................................................237
Nitrogen leaching from agricultural land has become evident for pollution of water resources in many regions of the world. Groundwater pollution has to be seen in a watershed context because in the long term it affects the quality of surface waters as well. Simulation models linked to geographic information system (GIS) provide a useful tool to assess the effects of different agricultural practices on water quality. A model was used to evaluate actual and alternative management practices in a nitrate-polluted drinking water catchment of northern Germany. Simulations are able to describe nitrate leaching for a given land use with sufficient accuracy. Scenario
