'''Slope-steepness factor''' or S factor – USLE is the ratio of [[soil]] loss from the field slope gradient to that from a 9 percent slope under otherwise identical conditions. Used in Universal soil loss equation (USLE) calculations of sheet and rill erosion. | '''Slope-steepness factor''' or S factor – USLE is the ratio of [[soil]] loss from the field slope gradient to that from a 9 percent slope under otherwise identical conditions. Used in Universal soil loss equation (USLE) calculations of sheet and rill erosion. |