Evaluation of ecological mesures: phosphorus losses by surface runoff

The effect of ecological measures in agriculture on the phosphorus contamination of waters caused in particular by surface runoff was investigated in the catchment area of the Lippenruti Brook in the canton of Lucerne. Within the scope of this investigation spanning 270 different fields, site, cultivation and dung spreading factors were examined and placed in a causal connection with the measurements made in the brook. In comparison to the phosphorus contamination of the brook at the beginning of the nineties, first results lead to assume a maximal reduction of 19 % of the contamination caused by agriculture.