The loess Plateau is characterized dy serious water and soil eresion. The most active soil erosion is in the small watershed in which sediment production is concentrated. There are the significant differences in erosion patterns

erodibility and sediment production in various landform locations in the small watersheds. The better results can only be obtained by having a good grasp of the rules and adopting effective controlling measures. The xihe watershed is a small watershed with serious water and soil erosion in Guanzhong basin. Affected by the rising of the Lishan Mountain

soil erosion here is so serious that the bulk of sediments are carried into the reserviors

which not only reduces the storage capacity and economic returns but also threatens the lives and properties of the people in the lower reaches. Therefore

it is necessary to strengthen work on soil and water conservation in the small watersheds in order to reduce sediment deposited in the reservoirs.