A field test of Root Zone Water Quality Model - pesticide and bromide behavior

The Root Zone Water Quality Model is a process-based model that integrates physical, chemical and biological processes to simulate the fate and movement of water and agrochemicals over and through the root zone at a representative point in a field with various management practices. The model was evaluated with field data for the movement of water and bromide, and the transformation and transport of cyanazine and metribuzin in the soil profile. The model reasonably simulated soil water and bromide movement. Pesticide persistence was predicted reasonably well with a two-site sorption model that assumes a rate-limited adsorption-desorption process with the additional assumption of negligible degradation of interaggregate-adsorbed pesticides.