Spatial Variability and Estimation of Information of Linear Nonstationary Soil Moisture in Farm Field

Taking Xiliao River Irrigation District, which is often drought in Spring and waterlogging in Autumn, as an example, this paper studied that the distribution characteristics of nonstationary soil moisture information with spatial drift at 5 different depthes from 0 to 100 cm in the field by the geostatistics theory. On the basis of revealing of spatial structure of soil moisture information in the sampling area, the followings were studied deeply:(i) the effect relationship between the spatial drift data and the observed scale of the soil moisture information; (ii) the differences between γ_Ｚ(h ) and γ_R(h ) and (iii) the differences of estimation regional soil moisture information between the Ordinary Kriging (OK) and Universal Kriging (UK) Method. The regional distribution estimations of the soilmoisture information by OK and UK are very closed to experiment values in h≤a. So OK method which is simply and can be used for the estimation of linear nonstationary soil moisture information in a large area. It is broaden for the field of geostatistics theory to be applied in the agriculture engineering.