The Heavy Metal Contamination And The Treatment In The Typical Vegetable Soils In The Suburb Of Nanjing

With the heavy metal contamination of the soil in suburb increasingly threatening the quality safety of vegetables, more and more attention has been paid to the problem of vegetables'quality safety. By studying the heavy metal contamination of the Soil-vegetable System in the typical areas locating in Liuhe and Baguazhou borough of Nanjing, the study researched into the contents and the distributing character of the heavy metals in different soil layers, and the concentration of heavy metal in vegetables growing in the researching site was also analyzed, in order that the results could provide important information to the choice of the vegetable fields in suburb and the treatment of the heavy metal contamination in soils in Nanjing. The main results were summarized as followed:1. The soil sampled from Liuhe and Baguazhou borough was contaminated by Cr,Cu and Pb. The extent of contamination decreased in the order of Cr>Pb>Cu.2. According to the evaluation, soil of Baguazhou borough suffered heavier contamination than that of Liuhe borough.3. The soil suffered combined pollution of Cr, Cu and Pb, according to the positive correlation between Cr and Cu, Cr and Pb, Cu and Pb respectively.4. Among the five vegetables, the orderliness of the contents of chrome and lead in vegetables was root>stem&leaf, and the orderliness of the contents of copper was stem&leaf>root.5. The strongest enrichment capability to chrome of the vegetable was rape; the strongest enrichment capability to copper of the vegetable was greengrocery, and the weakest enrichment capability to copper of the vegetable was rape; the strongest enrichment capability to lead of the vegetable was leek, and the weakest enrichment capability to copper of the vegetable was greengrocery and garlic.6. Estimated by superscale and compound factor ,the result was that the strongest enrichment capability was the leek and it was polluted the most badly.