SOIL LOSSES UNDER SIMULATED RAINFALL IN SEMIARID SHRUBLANDS OF THE EBRO VALLEY, SPAIN

Runoff and soil loss were measured using simulated rainfall at nine sh rubland sites on gypsiferous soils in the Ebro Valley. The sites repre sented diverse physiographical situations, inclusing three soil types, three slopes and different percentages of rock outcrop and vegetation cover. Soil tyoe, slope and vegetation cover significantly affected r unoff and soil losses. An average of 40% of the simulated rainfall (48 mm/h) appeared as runoff and amounts were positively correlated with soil losses. The greatest runoff and soil losses were from plots with the steepest slopes. Rock outcrops decreased soil losses.