| Abstract: | Results of computer simulations on fertilization and catch cropping problems in water protection areas by means of a soil nitrogen model A simple model of the nitrogen turnover in soil is presented. The model was validated by field experiment time series. The simulation results showed that dividing of the mineral nitrogen fertilization during spring for root crops or maize as well as shortening the first spring nitrogen fertilization for winter cereals diminished the leaching of nitrate only in extremely wet springs on sandy soils. The great importance of winter catch cropping in a cereal-root crop or a cereal-maize rotation on all soils and the necessity to avoid liquid manuring during late summer and early autumn, especially on sandy soils without catch cropping, are demonstrated. The results underline the predominant influence of the weather conditions on nitrate leaching. |
