Soil water characteristics of different typical land use patterns in water-wind erosion interlaced region

Five representative land use types were selected to monitor the soil moisture in Liudaogou Catchment,Shenmu County,northern Shaanxi Province of northwestern China,in the center of the water-wind erosion interlaced region from May to October,2004.The five land use patterns were Caragana korshinskii land,Glycine soia land,Setaria italica land,natural grassland and de-farming grassland.The data were obtained under the condition of natural rainfall,and the results showed that the dynamic change tendency of water-storage capacity of the five land use types was accordant with that of natural rainfall,and the maximum and the minimum capacity happened respectively in the first ten days of June as well as July;the moisture circulation processes of the five land use patterns were nearly all "consumption-compensation-consumption",and the variation scope of soil moisture decreased with the increase of soil layer depth;the sort order of the transpiration and evaporation capacity within the observation period was C.korshinskii land>natural grassland>de-farming grassland>G.soia land>S.italica land,and that of total runoff produced within the observation period was G.soia land>S.italica land>de-farming grassland>natural grassland>C.korshinskii land.For C.korshinskii land,its transpiration and evaporation capacity was the maximum while its total runoff was the minimum,and this shows that its efficiency of water application is high and it has better effects on the soil and water conservation,and cultivating deep-rooted plants is the potent way to prevent the soil erosion and utilize the deep subsoil water.