By establishing the runoff plots of three vegetation we carried on the site-specific observation on the soil moisture in the water-wind erosion crisscross region on the Loess Plateau,and analyzed the effect on seasonal variation of soil moisture and water use efficiency.Results showed that soil temperature at 5 cm depth was significantly below air temperature during the growing season;seasonal fluctuations of soil surface moisture at 0-6 cm depth was influenced by the temporal pattern of rainfall.Vegetation...