| The most serious erosion in the Loess Plateau exists in the wind-water erosion interleaving region where the annual precipitation is about 400 mm. The ecological environment is very fragile and water is the limiting factor of environmental restoration in this region. Salix psammophila and Caragana korshinskii are the important shrubs for vegetation construction and play an important role in controlling water and wind erosion. In this paper, the characteristics of precipitation and crown interception have been observed by the method of fixed hyetometer inside and outside of the shrub forest. The results showed that: (1) There was a linear positive correlation between rainfall inside and outside of shrub stands, and the correlation coefficients of Salix psammophila and Caragana korshinskii are 0.9985 and 0.9996, respectively. (2) There was a typical power function relationship between crown interception and precipitation, and the correlation coefficients are 0.8843 and 0.9187,respectively. The crown interception percentage was reduced with the increase of precipitation, and their correlation wasn't obvious. (3) The interception percentages of Salix psammophila and Caragana korshinskii in July and August were higher than those in September, and the interception percentage of Salix psammophila was lower than that of Caragana korshinskii. However, the interception percentage of Salix psammophila was higher than that of Caragana korshinskii in September. |