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Shanghai, China's large population, industrial development, pollution is very complicated. In this paper, a typical Shanghai urban green soil as the research object, the system of research and analysis of different land use patterns green soil Cu, Zn, Pb, Cd, Cr, Ni 6 kinds of heavy metals content distribution and morphological characteristics of black carbon content distribution and distribution characteristics of soil enzyme activities, as well as different environmental factors on Heavy Metals in Soil and soil enzyme activities. The results help to understand the characteristics of soil pollution in Shanghai Greenland for urban environmental management and protection provides an important basis. The results showed that: (1) Shanghai typical urban green soil, Cu mainly in the form of organic state; Pb and Ni mainly in the residual fraction form; Cr and residual organic forms-based; Zn mainly iron manganese oxide and residual forms. In contrast only the highest content of exchangeable Cd, accounting for 31.31%; six kinds of heavy metal and its various forms has a good correlation between the total resistance, and reached a highly significant correlation levels; respect between different forms , its relevance vary. (2) soil environmental factors on the impact of different forms of heavy metals is not the same. CaO, Fe2O3, and MnO in favor of heavy metals and residual organic generation, can reduce heavy activity; Cu, Zn, Pb, Cd, Cr and Ni 6 kinds of heavy metals, only zn iron and manganese oxidation state associated with Fe203 and MnO of the most significant. (3) the use of soil in different ways, influence species distribution of heavy metals is not the same: Cu office area residents active in the highest category, Zn machinery factory activity in the highest category, reagents Solvent exchangeable Cd content of the highest class. Relatively speaking before the city received more attention in Shanghai Greenland soil Pb basically an inert form of existence, hazardous relatively mild, the potential harm is not expected big. Ni in residual fraction, steel mills and shipyards class category manganese oxidation state of Ni content is much higher than the resident office machinery factory classes and community classes. (4) Shanghai typical urban green black carbon content of soil ranged from 0.70-78.89 g · kg-1, an average of 11.38g · kg-1. Machinery factory black carbon content, and an average of 18.30 g · kg-1. Black carbon and organic carbon, BC / OC values ??of the correlation reached a very significant level. (5) land use patterns in different green black carbon content of soil are not the same office area residents within-class black soil carbon content and BC / OC lowest, where BC / OC average class size of order shipyard gt; Steel Factory class gt; machinery factory class gt; reagent Solvent class gt; resident district office category, BC / OC average of 0.48. BC / OC maximum value appears in the steel mills, up 0.88. (6) Shanghai typical green soil, soil enzyme activity under different soil environmental factors. Catalase activity by soil bulk density, pH, CEC and Cr greatest impact; alkaline phosphatase by organic matter, hydrolytic nitrogen, Pb and zn greatest impact; dehydrogenase by the CEC, pH. Bulk density and hydrolytic nitrogen greater impact; hydrolytic nitrogen, CEC, pH and bulk density on urease greatest impact. Catalase, alkaline phosphatase, dehydrogenase and urease four kinds of soil enzyme on the nutritional status of the soil requires high; Cu, Zn, Pb, Cd, Cr and Ni 6 kinds of heavy metals on soil enzyme relatively small. Alkaline phosphatase reflect the nutritional status of sensitive soils.
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