THE APPLICATION OF CREAMS MODEL TO FORECASTING THE NITRATE AND CHLORIDE LEACHING FROM GRASSLAND

Pollution of groundwater due to nitrate is a serious problem in Poland . A significant part of this pollution originates from permanent grass land. The experimental results from four experiments conducted near Wa rsaw were compared and supplemented with the simulation made by means of the CREAMS model. A good agreement was found between the experiment al and the simulated balance of nitrogen as well as chloride. The esti mated nitro nitrogen concentration in percolated water was between 10 and 90 mg N/l, which presents a ma danger to the quality of groundwate r. The obtained results ascertained that the CREAMS model is a proper tool for forecasting the nitrogen balance on permanent grassland, part icularly the losses of nitrogen due to nitrate leaching. The chloride used as an experimental and/or calculated tracer to the nitrogen balan ce was shown to be advantageously valuable.