Study on Soil Moisture Characteristic of Different Land Use Types in Black Soil

Based on field fixed experiment in Hailun national field research station,dynamic change characteristic of soil moisture with different land use types were analyzed.The results showed that soil moisture(0-190 cm) presented increase-decrease with the increase of soil depth,and the difference of soil moisture in various land use types was significant in 0-30 cm soil layer,soil moisture increased in the order of corn landalfalfa landfallow landbare land.Soil moisture seasonal change was found in observation period,and was divided into three stages: relative stabilization,consumption and supplement stage.Based on variation coefficient of soil moisture,vertical change of soil moisture was divided into three layers generally: the active,the sub-active and relatively steady layer,and variation coefficient decreased with the increase of soil depth.