Nonpoint pollution from agricultural watersheds in the Carpathian Plateau (Southern Poland)

Abstract

In the Carpathian Plateau (Southern Poland) there are numerous strips and scarps which limit the rate of surface runoff. At the same time, a dense net of field roads intensifies the runoff. Investigations were carried out in 4 different watersheds. The greatest losses of nutrients during the spring thaw were observed in the watershed of the Mogiłka stream which was characterized by the greatest intensity of agricultural land use. The unit flow was accepted as the parameter which most synthetically illustrated the natural and anthropogenic conditions stimulating the occurrence of non-point pollution in the watershed. On the basis of regression equations the following values of the mean annual export of nutrients from the area of the Carpathian Plateau were calculated (kg ha⁻¹ yr⁻¹): N-NH₄—0.66, N-NO₃—3.61, N_org—6.14, N_tot—10.4, P_tot—0.68, K—11.0, Ca—121, Mg—27.