| Development of ecological environmental remediation and repair on reclaimed land has strategical meaning, which can effectively allivieate useness pressure of agricultural land and avoid pollution on agricultural product, and from which it embody scientific development view based on human and provide maintance logistics for environmental resource's sustainable development. This study take reclaimed land in Chongming Island as subject investigated, and research on heavy metal pollution and microbe community characteristic under different land use, and then through pot-culture simulated experiment, study on soil ecological molecule toxicological effect and improve soil health under heavy metal combined pollution. At last, two strain fungi which can tolerate Cd and Pb isolated from heavy metal polluted soil combined with chelate are applied to heavy metal polluted soil in order to improve phytoextraction efficiency. The main conclusion as follow:1. The highest heavy metal polluted areas of the Chongming Island are centralized in middle part of Chongming Island, and high Ni and Cr pollution in the western Chongming Island is the alluvial area of Yangtse River; the effect of industrial land use on heavy metal content in soil is significant, whereas the effect of commercial land on heavy metal pollution isn't observed, and eastern farmland and wetland are at low heavy metal index; Pb, Zn, Cu and Cd must be considered as key controlled object, in which must emphasize on controlling Pb and Cd pollution and Ni and Cr pollution in western Chongming Island.2. The soil DNA polymorphism bands under different land use is different, and the order of which is: agricultural land > commercial land > industrial land > wetland; the gene similarity of agricultural soil is significantly higher than that of other land use, and the gene similarity of wetland and industrial land are lower; the spatial evolving characteristic of soil enzyme and organic matter under different land use in Chongming Island follow gradually decreasing order : industrial and commercial land→agricultural land→wetland, and wetland reversely disclose soil health evolving process.3. Soil respiration and enzyme activity is higher under single Pb treatment than under single Cd and combined pollution, and plant is helpful to improve soil microbe and enzyme activity; soil gene polymorphism bands are higher under single Pb and combined pollution than under single Cd pollution; plant will improve soil gene polymorphism bands and richness and the order of improving soil enzyme activity under different culture manners is: mixed planting> monoculture> unplanted treatment.4. superoxide dismutase (SOD), malondialdehyde (MDA), total acid soluable thiol (TAST), total glutathione (GSH) and phytochelatins (PC) of hyperaccumulator change with heavy metal toxicity coefficient and significantly relate with heavy metal toxicity coefficient (y= a+bx+cx2, R2>0.95); SOD, TAST and PC of hyperaccumulator significantly express under heavy metal stress, and the detoxification function of TAST and PC in different plant is different.5. Addition of critic acid or microbe can enhance 30-45% Solanum nigrum. L biomass under Cd and Pb combined pollution, and the order of biomass under different treatment is: combined application> addition of critic acid > addition of microbe > control > no addition of critic acid or microbe; combined addition of critic acid and microbe can enhance 30% Cd accumulation in plant, and the order of transfer coefficient for Cd is: combined application> addition of microbe > addition of critic acid > control > no addition of critic acid or microbe; Solanum nigrum. L don't show significantly hyperaccumulating characteristic on Pb, and Pb accumulation is centralized on root and the item and leaf in Solanum nigrum. L is at low extraction coefficient; additions of microbe significantly enhance Pb accumulation on plant and addition of critic acid decreases Pb accumulation reversely.
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