SPATIAL DISTRIBUTION PATTERNS OF Cr AND Ni IN SOILS OF BEIJING
北京市土壤中Cr,Ni含量的空间结构与分布特征

The knowledge of the distribution of heavy metal concentrations in soils is the base of environmental quality assessment of soils. Geostatistics is an appropriate method to study the spatial distribution patterns of soil heavy metals. Using geostatistical methods it was found that the semivariogram of Cr and Ni in soils of Beijing showed good transition character, which could be fitted well using the exponential model. The ranges of Cr and Ni were 174.6 km and 15.0 km, respectively. The spatial structures of Cr and Ni were isotropy. The distribution patterns of Cr and Ni were high in the north of Miyun County. So the soil environmental quality should be paid much attention to this area. The results show that the distribution patterns of Cr and Ni presented the variations of heavy metals in different districts and the Kriging method could provide with a suitable way to identify the contamination sources.