Study on Erosion Factors Affecting Kuroboku Soil Loss I. Water Permeability of Stratified Soil and Slope Gradient

The authors examined the factors of bed soil affecting the loss of surface soil and the effects of these factors on the extent of the soil loss. They conducted a multivariate analysis using actual measurement value at a laboratory erosion experiment. They also conducted a simulation of erosion in soil loss using the bed soil factors. Soil loss quantity is dependent on the coefficient of permeability of bed soil; the steeper the latter is, the more the former increases. Lateral soil scattering quantity is not much affected with the permeability of bed soil, nor with the gradient of a slope. When the slope gradient of bed soil is equal, soil loss quantity is affected with the coefficient of permeability and the ignition loss of the bed soil. On the otherhand , when the slope gradient of bed soil is different, soil loss quantity is most affected with the slope gradient, followed by the coefficient of permeability of the bed soil