| In this thesis, the present situation of heavy metal(Cd,Cr,Cu,Zn,Pb,Hg,As) pollution of vegetable garden soils and vegetables in Guiyang city suburbs was investigated and evaluated. the change tendency as well as the influence to vegetable security of the heavy metal content in Guiyang city suburbs had been forecasted.main conclusion were as follows:. The results were showed as follows:1.The average contents of Cd,Cr,Cu,Zn,Pb,Hg,As in Guiyang city suburbs' vegetable garden soils were higher than the background values of Guiyang city soils. The vegetable garden soils have been polluted by Cr and Hg.2.The vegetables in Guiyang city suburbs were polluted by Pb ,Hg and As. Pb, As pollution was the most serious, following by Hg, but the vegetables were not polluted by Cd, Zn. Size order of the concentrate ability of different vegetables to the homogeneous element are as follows: Cu:Cabbage>Celery> Lettuce Pb, Cd, As, Cr: Lettuce>Celery>Cabbage Hg, Zn: Celery> Lettuce>Cabbage3.According to relations between soil heavy metal entire quantity as well as the effective quantity and the vegetable heavy metal content, the entire quantity of As, Cr and Hg in the soil had good relevance with content of As, Cr and Hg in the vegetable, other elements relevance missed.4.Through the analysis of soil heavy metal content change in Guiyang city suburbs, in next period of time the key pollution element in this area was most possiblly to be Cu, if the increasing speed of soil content achieved 2.321mg/kg each year according to calculates now, about 55 years later, the soil Cu content value would surpass the present value of soil environment quality level 2. The lettuce plant which in this section of time in the vegetable production base could all achieve food health standard.5.through this research , the pollution degree of the heavy metal in different region were obtaied as follows: the industry and mining area > the suburb area > the outer suburb.
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