Description:
The accuracy of simulating the trifluralin concentrations in a clay soil and in a loamy sand soil with the modified CREAMS/GLEAMS model has been tested by comparing them with observed values. The simulated concentrations in the soils were in good agreement with those observed in the first weeks after application. In the long run the simulated concentrations decreased faster than the observed ones. In addition, the sensitivity of the model to variations of two pesticide parameters has been analyzed: the pesticide adsorption coefficient for organic carbon and the pesticide degradation rate expressed as half-life in soil. The variation in the two pesticide parameters had a considerable effect on the model output. Especially large were the effects of the adsorption coefficient on the pesticide concentration in the percolated water leaving the root zone.