SIMULATION OF ATRAZINE LEACHING IN RELATION TO WATER-TABLE MANAGEMENTUSING THE CERES MODEL

There is a lack of models to predict the effect of water-table managem ent on pesticide leaching. The objective was to modify CERES (Crop Est imation through Resource and Environmental Synthesis), a soil-crop-atm osphere model, to be a decision-making tool for water-table management in relation to pesticide leaching. CERES is a functional model that s imulates all basic plant and soil processes with moderate data and har dware requirements. Data from five field lysimeters planted with maize (Zea mays L) and sprayed with atrazine loro-4-ethylamino-6-isopropyla mino-1,3,5-triazine) were collected to calibrate the model. The water- table in the lysimeters was raised and drained at two different growin g stages and for two different durations. Simulation results for soil water content and atrazine were reasonable. Simulation can be used to estimate the leaching intensity, a decision criterion to select strate gies to mitigate environmental impact. (C) 1998 Academic Press Limited .