Nutrient loads cause eutrophication, and the non-point characteristics of this pollution problem has been studied for decades. Efforts have been made to reduce nutrient loads and eutrophication in Europe, US and elsewhere, but additional actions are required to achieve good water quality aimed for in water quality policies. Spatial data describing the relationships between biophysical and
hydrological factors and agricultural production have been used to develop an ecological-economic model of the non-point pollution and the spatial configuration of the costs to reduce the loads. The model has been developed to analyze the cost-effective choice of abatement measures taking the nonpoint and diffuse distribution of the loads of nitrogen to the sea into account. The model is a cost-minimization model at a fine spatial resolution which identifies spatial distributions of the costeffective implementation of abatement measures. The model is developed to analyze and compare the costs and effects of uniform regulation versus spatially differentiated implementation of abatement measures, as well as how model assumptions affect the model solutions. Both types of
analyses are regarded important for the use of this type of models in policy advise.