Abstract：Vegetative cover plays an important role in reducing soil and water losses.Based on the meteorological and hydrological data and the observation data of forest and grass plots in Nanxiaohe watershed from 1954 to 2004,relations among erosion intensity,runoff,precipitation and vegetation coverage was quantitatively analyzed.Results showed that: 1) Effect of forest and grass coverage in reducing slope erosion was obvious.2) Significant demarcation was found when vegetation coverage reached to 40 percent to 60 percent in controlling water and soil loess.3) From the view of soil erosion control,effective vegetation coverage of artificial forest stand and grassland in Hilly-gully Region of Loess Plateau should not be lower 50%-60%.
2008, Vol. 6 
