The objective of this paper is to present a model based approach to identify the demand for measures for the reduction of nitrogen surpluses from agriculture and to compose a combination of possible measures with their associated costs to be able to meet the targets of the water framework directive (WFD). An interdisciplinary model network consisting of the regionalised agricultural economic model RAUMIS and two hydro(geo)logical modelling systems GROWA/WEKU and MONERIS is used to analyse the spatially differentiated impacts of nutrient reduction measures on the water quality of groundwater and surface water. The study region of the German Weser river basin is chosen that comprises 49,000 km2 and features heterogeneous natural site conditions. In order to support the preparation of a management plan for the Weser river basin the AGRUM Weser project has been initiated. A combination of measures is specified for each county in the Weser basin depending on regional peculiarities and farming practices. Results show that about 100 million Euros per year are needed for agri-environmental measures to fulfil the objectives of the Water Framework Directive. This paper presents a regionally comprehensive and area wide modelling approach that is capable of linking hydrological and agricultural economic aspects in an interdisciplinary approach and which can easily be transferred to other river basins.
Water framework directive, Diffuse pollution, Agricultural economic and hydrological modelling, Cost of nutrient reduction measures, Weser River Basin
Kreins, P., Gömann, H., Heidecke, C., Hirt, U., Wendland, F., 2010. Modelling network for analysing diffuse nitrogen leaching reduction in agriculture to meet the targets of the water framework directive in the Weser River Basin of Germany. In: Steusloff, H. (ed.). IWRM Integrated Water Resources Management Karlsruhe: KIT Scientific Publishing, pp. 200-206.