Prediction of groundwater nitrate pollution in the Upper Rhine Valley Aquifer using the model family MoNit

Abstract : Prognosis of the development of the nitrate pollution in the Upper Rhine Graben Aquifer shows a decline of concentrations due to significant reduction of nitrate input with recharge in the past. However, the estimation of historical input is rather unsure, therefore the predictions should be verified-by surveys in the next years. Even in 2050 a good Status of groundwater quality with concentrations below 50 mg/l will not be reached everywhere. Scenarios of the evolution of the agricultural land use in the Upper Rhine Valley suggest a decrease in cultivation of corn. This does not always lead,to an additional decrease of nitrate groundwater pollution. The situation could be improved by supplementary measures, whose efficiency has been evaluated in the project. Best of these was a combination of strictly demand-oriented fertilizing, intertillage und extensivation of 20 % of the arable, farm land.