| Soil is the medium with biological and gas structure in the Earth's land surface that is also the fragility of Earth's land surface thin-layer。It is the result of the combined effect of natural factors and human activities for long time. With the acceleration of the process of global industrialization, human beings are faced with the dying of resource and environmentalpollution.This is a very serious question. Therefore, doing something on remediation of soil treatment and following the path of sustainable development have become a basic national policy of our country's development.This thesis bases on the dates of the item which China Geological Survey gave that is Soil Geochemical Subdivision Of Chong Qing Metropolitan Area.According to data statistic and space analysis, the article study the metals distributed characteristic in soil environment of Chongqing metropolitan area and to summarize their enrichment disciplines, using three different indexes and integrating national soil environmental quality standard to evaluate the soil quality of Chongqing metropolitan area. Based on the research result, getting a comprehensive evaluation of soil .The main conclusions of study show following:(1)The abnormal area of As ,which is the only one of fifty-four elenments is over standard in 30% area in surface soil. The abnomal area of B,I,Mo,U,Hg,Se,Cl,Sb is 20-30% area and S,Au,CaO,Zr,Li,Sn,F,Corg,Ag,Ti,SiO2,Cr,N,Br,W,Bi,Nb,V,Th,Pb,Cu is 10-20% area. The abnormal area of the remaining elements is less than 10% area.(2)The landform of the investigable area is low mountains and hilly topography area.Characteristics of the elements of soil succeed ones of rock obviously. Mudstone, sandstone is the measured area of the most extensive distribution of the rock. Soil in carbonatestone area has the highest value of the majority of elements but soil in sandstone area has at least a high content of elements in Various types of rock areas.(3) Discovering enrichment coefficients of the content of six heavy metals, As, Cu,Zn,Pb,Cd and Hg, in surface soil to deep soil are over 1,which demonstrates that these metals been effected from outside migration. The enrichment coefficients of Cd and Hg are over 2.2 and 1.5, showing that the effecting from outside environment is strong. The degree of Cr,Ni in surface soil is low.(4) According to the study of enrich different heavy metals from the soil. The different plants enrich different heavy metals are different. Based on this factor, the result shows that the content of heavy metals in rice seed is higher than other crops but Pumpkin is the lowest in all crops. So It is ought to warn and void in agriculture industry structure.(5)According to data analysis and space integrated for surface soil samples from Chongqing metropolitan area and comparing the national soil environmental quality standard, evaluating the soil quality of Chongqing metropolitan area to carry out evaluation of the classification. The research result shows that soil in research area mostly is graded as fine,which accounts for 71.7% and higher contents of Se in several areas of rnvestiguted areas.(6)Using the research result of geochemistry, the article proposes the extend directions of city subdivision of Chongqing in the first time. The direction of North East is the priority extend direction, the South West is the second priority extend direction, the North West is requirement limited direction, and the South East is limited direction. The Jielong,Shentong,Daguan and Lingfen region can be priority to develop green food and to establish the bases of green industry for the Vegetable Basket Project.
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