Abstract

Dynamic simulation models are required to predict the future nitrate pollution of groundwater and surface water by agriculture, to derive maximum permissable nitrogen loadings and for evaluation of various nitrogen emission scenarios. A suitable dynamic simulation model should be applicable to all major combinations of soil type, land use and management scenarios. For this purpose the dynamic process oriented N-cycling model SOILN was implemented at the RIVM for evaluation of the nitrogen surplus problem in the Netherlands on agricultural soils. The model was originally developed and provided to us by the Department of Soil Science of the Swedish University of Agricultural Sciences. At the RIVM the model was adapted for soils under grassland and grazing. This report summarizes model principles, provides guidelines for model use and gives examples of model output for a case study on a farm in Laren, Gelderland.