Changes of the concentrations of dissolved chemical compounds migrating into ground water through biogeochemical barriers in an agricultural landscape

Forms of nitrogen (N-NO₃^-, N-NH₄⁺, N-org) and phosphorus (P-PO₄^-3, P-org) were investigated in ground and surface water as well as in precipitation and run-off. The highest concentration of all the investigated compounds was determined in the drain and in run-off. This investigation shows that afforestations and small ponds function as very efficient biogeochemical barriers with regard to N-NO₃^- and P-PO₄^-3. They do not, however, limit the spread of P-org.