Variability of Soil Moisture of Shifting Sandy Land and Its Dependence on Precipitation in Semi-arid Region
Wenzhi Zhao · Zhongguo shamo · 2002
Soil moisture data from May to October during 1983 to 1990 at Naiman on Horqin Sandy Land are applied to study the temporal and spatial variability of soil moisture in shifting sandy land, and to approach its dependence on precipitation. The mean soil moisture at the depth of 0～300 cm varies between 3.25% and 3.47%, and with not significant difference between layers. On the other hand, soil moisture exhibits temporal variability. Soil moisture on May is different significantly from that on June, July, Aug. Sept. Oct. respectively. However, soil moistures on June, July, Aug. Sept. Oct. are not different significantly from each other. Although annual precipitation varied from 243.3 mm to 567.1 mm with a variance coefficient of 95.09% during 1983-1990 at Naiman, soil moisture in shifting sandy lands varied only from 3.10% to 3.69% with a variance coefficient of only 18.68%. Soil moistures at all profiles are correlated with the monthly precipitations. Furthermore, soil moisture at depth from 0 to 40 cm has not significant correlation with the precipitation in former month, but that at depth from 40 cm to 300 cm does.