Investigation And Assessment Of Heavy Metal Pollution In Main Agricultural Product And Environment Of Cangnan County

The situation of heavy metal pollution of soil,water and agricultural products in 13 bases of agricultural products of Cangnan county was analyzed and evaluated.The aim of the research is to prove up the cause of heavy metal pollution of agricultural products and the impact of the heavy metal content of soil on agricultural products.Following conclusions were achieved:1.The quality condition of main agricultural products:the synthesis pollution indexes of 4 paddy bases(Jingxiang,Tengyang,Mazhan and Yishan) and 4 vegetable bases were under 0.7 which were under the safe-food standard. The main pollution element of paddy was Pb.The laver from 5 aquatic product basts had been polluted by heavy metal As.The razor clam and silver carp were still under safe-food standard while the razor clam had been polluted slightly.2.The quality condition of agricultural environment:The environments of 4 paddy bases and 4 vegetable bases were clean which can develop green-food.The Hg pollution indexes of soil in Jingxiang exceed 1.0 suggesting these spots had been polluted by heavy metal Hg.The environments of 5 aquatic bases were clean which can develop green-food. The Hg pollution indexes of Dayu exceed 1.0 suggesting these spots were in danger of heavy lnetal pollution.3.The impact of the heavy metal content on agricultural products:There were significantly positive correlations between the concentrations of Hg, As and Cd in paddy and the content of them in paddy soils,which meant the sources of Hg,As and Cd in paddy were paddy soil.There were no significantly correlations between the concentrations of Hg and As in vegetable and the content of them in vegetable soils which meant the main sources of Hg and As in vegetable were not soil.Pb and Cd in the soil had not been absorbed by vegetable on them.There were no significantly correlations between the concentrations of Cr,Cd and Pb in aquatic products and the content of them in aquatic soils.The content of Cr,Cd and Pb in aquatic soils had been tested while there were no Pb in all aquatic products and Cr,Cd in most aquatic products,which suggested the heavy metal of soil were not the main source of heavy metal of aquatic products.