The spatial distribution of topographical categories on the Loess Plateau is shown in Fig. 6, and the rates of soil erosion for these categories are given in Table 4. The highest erosion rates were on midslopes, followed by valley. Rates on ridges, upslopes and downslopes were similar, and flat areas had much lower erosion, exhibiting the same trend as variation.
The topographical categories were closely related to the LS factors. The highest LS value was also found on the midslopes of the mountain areas of the Loess Plateau, followed by upslope, ridge, downslope and valley. The lowest LS value was distributed on the flat areas,
most of which lie in the northwest of the Loess Plateau in Inner Mongolia, the central part of Shanxi province and south of the Loess Plateau in Shaanxi province