Soil Water Modeling in South Georgia using WEPP Hydrology

摘要

Soil water is a fundamental component of any field or watershed scale water balance. A basin scale soil water model is being assembled using the runoff and water redistribution functions within the WEPP model. The model uses the runoff, infiltration,plant uptake, and water redistribution functions within WEPP to make predictions of soil water within the vadose zone. The WEPP model was evaluated using runoff and soil water data collected from South Georgia experimental plots where the effects of conservation tillage were examined. WEPP model simulations of surface runoff from the plots were within 30% of the observed annual runoff for the years used for calibration but varied considerably for the years used for model validation. In general, resultswere better for the simulations of the strip tillage system than for the conventional tillage system. Simulations of soil water in the upper profile were useful for examining seasonal patterns and for examining differences between the two tillage systems.