Spatial variability of soil water content and electrical conductivity in field for different sampling scales and their nested models

Using geostatistics, spatial variability of soil water content and bulk soil electrical conductivity was analyzed in the L (90m90m), M(30m30m, nested in the L ) and S(10m10m, nested in the M ) area of summer maize fields The results indicated that, no significant differences were in the standard error and coefficient of variation (CV%) of soil water content among the different scales, but such differences were in bulk soil electrical conductivity Water content was distributed normally or log normally in L and M, but it was only distributed log normally for 0.01 confidence level in S area Electrical conductivity was not distributed normally or log normally in S, but it was distributed normally or log normally for 0.01 confidence level, log normally for higher confidence levels in M, and log normally for 0.05 and 0.01 confidence levels in L area Semivariograms showed spherical models with the range of 2.2～19.8m and 2.5～17.2m for water content and electrical conductivity among different scales And it was suggested that nested models should be created when significant differences were showed among the models of different scales In addition, nested models were used to describe the spatial variability of soil water content and electrical conductivity among the different scales