EVALUATION OF THE GLEAMS MODEL FOR PESTICIDE LEACHING IN SWEDEN

The complexity and expensive nature of experimental procedures necessi tate the use of mathematical models for evaluating the fate of agricul tural chemicals as they enter into the soil and plant system. However, a transport model should be calibrated and validated for varying clim atic, soils, geologic, and land use scenarios before it can be used wi th acceptable levels of con fide nce. Leaching data from lysimeter exp eriments conducted in Mellby soil near Uppsala, Sweden were used to ca librate and validate the Groundwater Loading Effects of Agricultural M anagement Systems (GLEAMS) model. Although this model is a field-scale model for evaluating the relative impacts of agricultural management systems on surface and groundwater quality, it was put to the test for a leaching study through lysimeters. The results indicated that the G LEAMS model is capable of predicting both water and pesticide leaching through lysimeters in a reasonable manner. The study also concluded t hat any