Application of Semi-variogram and Moran's I to Spatial Distribution of Trace Elements in Soil:a Case Study in Shouguang County

The spatial distribution of trace elements in Shouguang soil was studied though semi-variogram analysis and Moran's I methods to research the difference and veracity of different spatial analysis methods.The results show that there is good spatial structure of trace elements in Shouguang soils,and the spatial correlation degree is higher in surface soil than that in deep soil.Either in surface soil or in deep soil,the spatial correlation distance of the elements obtained from the semi-variogram analysis is about 20~60 km,but the positive autocorrelation distance obtained from spatial autocorrelograms is about 20~25 km.the negative autocorrelation distance is about 25~55 km.The spatial autocorrelation degree reaches the significant level except of the variable Zn in deep soil.The Moran's I is more accurate than semi-variogram in spatial correlation analysis of soil elements.