Less nitrate in groundwater due to ecological measures

The impact of agricultural management on the nitrate content of groundwater in the canton of Berne was investigated with the substance flow model MODIFFUS. The nitrate content decreased on average by 12 % between 1990 and 1999, varying widely between regions. The results partly were in line with a dataset of measured values from groundwater wells. Nitrate contents mainly decreased because more main crops with low leaching losses and more catch crops were grown and less fertilizer and manure nitrogen was applied in arable farming. Probably more than half of the reduction was due to the introduction of ecological measures in agriculture in 1993.