Effect of antecedent soil moisture content on rainwash erosion

The effect of antecedent soil moisture on rainwash erosion was evaluated in a series of field experiments by using 0.84 m2 erosion plots and the modified Toronto simulator which delivered artificial rain at an intensity of 50 mm hr−1 (0.38 J m−2 s−1 kinetic energy). It was observed that antecedent moisture content is a significant factor contributing to variations in measured rainwash eroson. Extrapolation from the collected data suggests that rainwash differs by 4 to 5 times if the full range of antecedent moisture content is considered. For the soils tested which are cohesive in nature, the effect of antecedent moisture is not confined to enhanced runoff capacity, but also shear strength reduction.