HEAVY-METAL CONCENTRATIONS IN SOILS AND CROPS OF BAOSHAN-WUSONG AREA, SHANGHAI, CHINA

Sampling around the Baoshan-Wusong area indicated that concentrations of heavy metals in soils were higher than the background levels of agricultural soils of Shanghai-suburbs. Statistical test showed Zn, Cd, Cr, Hg, F, and Pb contaminants were present in the surface soils, and high correlation coefficients were identified between the soluble fraction of those contaminants in soils and their concentrations in wheat grains and leaves. To characterize its spatial variation, the fuzzy pattern recognition was introduced to assess comprehensively polluted conditions at sites, and logarithm regression was used to identify the main polluted source. Results showed that soil pollution occurred predominantly around the industrial complex, covering about 20 sq.km but was not widespread. This finding plus other statistical data revealed that the high level of metal concentrations were primarily due to industrial activities but not from soil parent materials and farming practices. The metal concentrations decreased with the increasing distance away from the complex along the southeast direction. © 1990.