Study on soil moisture content under different land use types in Sunjiacha basin

The characteristics of annual and seasonal changes of soil moisture in Sunjiacha basin from 1982—1983 and in 2011 were measured and analyzed.The results show that in the small watershed of loess hilly region, the change trend of soil moisture in a year is basically the same in farmland and wasteland.The soil moisture is strongly influenced by rainfall and its spatial and temporal distribution.The variability of soil moisture decreases with the increase in soil depth and rainfall.The dynamic changes of soil moisture in 1.20～1.40 m layer are significantly affected by seasonal climate,while soil moisture has temporal stability in the same year when soil depth is more than 1.60 m.Growing suitable crops(such as potato) in wasteland with good soil can improve water use efficiency in the gentle slope area(5°～15°).