Interrill Soil Erosion Processes: II. Relationship of Splash Detachment to Soil Properties

Abstract

AbstractSoil erodibility is often estimated using predictive equations based on easily measurable soil parameters. However, most predictive equations are valid for a limited group of soils and do not account for temporal changes in surface conditions. The objective of this study was to identify those soil properties that affect interrill splash and to develop an interrill detachment model based on both static and dynamic soil properties. Twenty soils ranging in texture from sand to clay were exposed to laboratory simulated rainfall with an intensity of about 63 mm/h. The development of a surface seal decreased infiltration rate, splash, wash erosion, and increased soil strength, as measured with a fall‐cone device. The best predictor of soil splash for the surface sealed condition was a combined kinetic energy/fall‐ cone strength (KE/τ) and total silt content term, and of total soil loss, a KE/τ and coarse silt content term. Comparing results from this study with previously reported studies, we conclude that for improvement of laboratory based indices, greater attention must be given to dynamic soil properties such as the soil's resisting force to raindrop impact and surface flow.