Effects of sampling scale on the spatial heterogeneity of soil moisture in desert steppe

Statistical analysis and Kriging interpolation method were used to analyze spatial heterogeneity of soil moisture in desert steppe of Siziwang Banner, from a variety of sampling scale. The results showed that with the increasing of sampling scales, the soil moisture spatial heterogeneity firstly increased, then slightly decreased and finally trended to be stable. The spatial heterogeneity of soil moisture in desert steppe is affected by microtopography of sampling plots and distribution of bushes. The appropriate sampling scale to study spatial heterogeneity of soil moisture in desert steppe is (4~6) m×(8~12) m.