Abstract:

Through sampling and analyzing rice grains and cultivation-layer soils , the distribution characteristics of soil trace elements and the main factors influencing elements transfer in soil-rice system were studied in the anomalous areas of eastern of Zhejiang Province. The results showed that mass fractions of some trace elements were higher than the regional geochemical background values in each study area. Especially, the average mass fraction of Hg was six times more than regional geochemical background value in the south of Wenzhou, Cd was five times in the Zeguo of Taizhou, and Hg was three times in the north of Shaoxing area. In these seven studied area, only in Xinsheng of Jiaxing area, the average mass fracrion of As was higher than regional geochemical background value. Industrialization rapidly and anthropogenic influence were the main reasons of the pollution. As, Cd, Cr, Hg, Se and Pb mass fractions in rice did not exceed tolerable concentrations in the north of Shaoxing, Xinfeng of Jiaxing, Xinsheng of Jiaxing, and Chongfu of Tongxiang.The transfer factors of potential toxic elements from soil to rice grains usually had a good relationship with soil properties including organic matter, pH, CEC and granularity. The transfer factors of As, Cd, Cr and Ni tended to increase as soil organic matter increased and decrease as pH increased. CEC, fine silt and clay component had negative effects on rice's transfer factors of As, Cu, Hg, Mn, Pb, Se and Zn.

Key words: geochemistry, trace element, soil property, transfer factor, eastern of Zhejiang Province