Soil Moisture Changes of the Mountainous Area in West of Guizhou under the Conditions of Severe Drought of Southwest China

CHEN Li;CAI Xiong-fei;WANG Ji;Gulin Construction Engineering Quality Supervision Station;School of Geographic and Environmental Science,Guizhou Normal University;

severe drought in southwest China;;soil moisture;;west of Guizhou

In 2010,the severe drought in southwest of China had seriously interfered the regional ecological environment and the surface vegetation experienced a rigorous test. The paper selected Panxian Country of Guizhou,which was one of the worst affected areas with the disaster as the study area,conducted stratified sampling at the 0-60 cm soil of different slope positions of woodland,shrub land and farmland and analyzed the soil moisture and its variation law under the conditions of extraordinary drought for providing references for the study on disaster prevention and reduction and related issues of drought disaster of the region. The outcomes show that a) the soil moisture in different land covers and different slope positions shows a gradually increasing trend from the surface to 60 cm deep soil. The soil moisture has a linear correlation with the soil depth; b) the differences of the soil moisture in different types of land cover are woodland > shrub land > farmland. The difference of soil moisture in corresponding soil layer between woodland and shrub land varies from 3. 55% to 6. 30%,between shrub land and farmland varies from 5. 24% to 16. 77% and between woodland and farmland varies from 11. 19% to 21. 08%; c) the differences of soil moisture in corresponding soil layer between downhill and uphill woodland vary greatly. The soil moisture in corresponding soil layer of different slope positions between shrub land and farmland changes a little. The thickness of soil layer has greater impact on the soil moisture of different slope positions.