EN
Paper presents the results of investigation in the Pożary basin located within the Kampinos National Park (central Poland). Almost 40% of basin area are wetlands enclosed partly in strictly protected areas. The main task in the first phase of project was the recognition of environment components influencing on migration of chemical substances. In May 1999 the measurement network (mostly piezometers) in the Pożary basin was established and 20 measurement sessions between June 1999 and June 2000 have been made. Investigation focused on following parameters: amount of precipitation, stream flow, groundwater level, as well as chemical properties of rain-, stream and groundwater: conductivity, pH, redox potential, hardness, concentration of dissolved Oxygen, Calcium, Ammonium, total Iron, Chloride, Nitrite, Nitrate, Phosphate and Sulphate. The results of field measurements are pointing at biogeochemical processes acting in the wetlands and groundwater recharge from outside the basin as the main source of chemicals. Higher concentration of Nitrate and Phosphate in groundwater, observed in the southern part of the basin seems to be an evidence of outer farming activity impact on protected area. Investigation was granted by Polish Committee for Scientific Research.