[Spatial variability analysis of soil arsenic in Zibo maize producing area, Shandong Province]

Spatial variability and distribution of soil arsenic in Zibo maize producing area, Shandong Province were studied using geostatistics and geographic information system (GIS) techniques. Positive skewed distribution was observed; Logarithm transformation was applied in order to achieve normality in the data set and to reduce the affect of outliers. The results show that experimental semi-variogram exists distinct anisotropic and has the strongest continuity in the direction of northeastern 70 degrees. Exponential model was used to fit experimental semi-variogram. Normal kriging was used to predict the spatial distribution of soil arsenic in Zibo maize producing area. It can be concluded that there is clear special heterogeneity in soil arsenic and wastewater irrigation is the main reason affected spatial variability. In fact, the concentrations of soil arsenic in Zibo maize producing area decrease in the pass 20 years.