Predicting soil loss on moderate slopes using an empirical model for sediment concentration

SummaryThe objective of this investigation was to estimate event soil loss per unit area from bare plots in central and southern Italy using an empirical model for sediment concentration. The analysis was developed using data collected on bare plots differing in length (11–44 m) and slope (10–26%) at three Italian stations (Masse, Umbria; Caratozzolo, Calabria; Sparacia, Sicily). At first, an analysis was carried out, using the experimental data collected at Sparacia, to establish a relationship between sediment concentration and hydrological variables, such as runoff, rainfall amount and single storm erosion index. Then, an empirical model to estimate plot soil loss as a function of rainfall amount, single storm erosion index, runoff amount, and slope length was developed. Finally, using the complete data set (Masse, Caratozzolo, Sparacia), the model was extended to include soil erodibility and slope steepness effects on plot soil loss.

Research highlights► Predicting event plot soil loss by empirical modeling has practical importance. ► Runoff is a primary independent factor in modeling rainfall erosion. ► Event soil loss was estimated by an empirical model for sediment concentration. ► The model considers the main factors affecting the soil water erosion process. ► The empirical nature of the analysis suggests the need of further investigations.