Determining the variability of soil erodibility for erosion prediction

Soil erodibility refers to the susceptibility or resistance of a soil to detachment and transport by erosion for a particular site. Accurate prediction of soil erosion strongly requires a sufficient understanding of the variability in soil erodibility parameters. The author reviews the existing knowledge on these topics and defines research gaps. In the framework of soil erosion prediction studies it is important to consider soil erodibility at various temporal and spatial scales. Little research has hitherto been conducted on quantitative assessment of spatial variability in soil erodibility and its relation to soil condition factors at different landscape level. But such information on this aspect is crucial for quantitatively describing the paths of erosion and to develop solutions or conceptions to interrupt these paths within the landscape. From this review, it can be concluded that special attention must be paid to the quantitative assessment of soil erodibility at various scales up to the catchment scale. The results of such studies should be used to relate erodibility parameters to soil condition factors that can be measured easily and confidently. Caesium-137 approach would be a reliable method for determining spatial variability in soil erodibility within the landscape, which has fast, inexpensive and accurate advantages over many classical measuring techniques