Prediction of Pesticide Behavior in Paddy Field by Water Balance on the Water Management Using Pesticide Paddy Field Model (PADDY)
The improved version of the pesticide paddy field model (PADDY) was evaluated for the prediction of pesticide concentrations in water and soil considering water balance on the water management. Field studies under the two different conditions on the water management practices, continuous irrigation and drainage, and water holding management that regulate drainage during the experimental periods, were performed to validate the improved model using molinate and simetryne. For both pesticides, concentrations in paddy water were the same level during the first day after the application on both fields. After second day, pesticide concentrations on the field for continuous irrigation and drainage were lower than those on the field of water holding management. Good fits between model predictions and field observations were obtained for the two pesticides by considering the water management and hydrological condition. |