Present State And Sources Identification Of Urban Environmental Geo-chemistry In Siping City

The papers described the generation and definition of urban environmental geochemistry, characteristics of heavy metal pollution of urban soil, sources and toxicity overall, select the Siping City, atmospheric dry and wet deposition and surface soil as the research object, the use of mathematical statistics As,Cd,Cr,Cu,Hg,Pb,Zn seven kinds of heavy metal content and pH-value were analyzed statistically using single-factor pollution index method, geo-accumulation index and Nemero comprehensive pollution index method combined with environmental quality grading standards to evaluate the heavy metal content, content distribution using MapGis software to draw maps and pollution assessment maps, the final factor analysis using atmospheric dry and wet deposition of Siping City, and sources of heavy metals analysis. Come about:1. Samples of each sampling point pH-value of precipitation show some seasonal variation. Heavy metals in atmospheric precipitation in the general performance of the autumn and winter high, low spring and summer..Precipitation of heavy metals in addition to Pb content of samples collected over the fall II standard, other samples were low Class II standard in which heavy metals Hg, Cr and Cd content is lower than standards for Class I2. Dry and wet deposition of heavy metals in the atmosphere vary widely, Cr, Cd content did not change significantly with the seasons, As content in the heating period than non-heating period, whereas the Cu, Hg, Pb and Zn content is lower than the heating period non-heating period, that is higher in summer and autumn. As, Cd, Cr, Cu, Hg, Pb and Zn in atmospheric deposition of total dry and wet deposition were 171.11,11.52,322.12,324.31,2.57,505.93 and 2180.73kg/a.3. Siping City soil pH-value slightly higher than the background value, indicating a certain alkaline trend. Siping City of heavy metals in significantly affected by human activities, the average content of heavy metals were significantly higher than the national, Siping City, Jilin Province, and the surface soil background value.4. Analysis showed that the spatial structure of heavy metals, Cu, Pb content is mainly affected by human factors. As by random factors and natural factors together. The remaining elements are mainly controlled by natural factors, little interference by man-made factors.5. The chemical speciation of soil heavy metals content, while not the same percentage, but the percentage of the contents were almost the same trend, As, Cu and other heavy metals are the six residue form; Cd In contrast, the main state ion exchange and carbonate and other active state exists. The chemical forms of heavy metals and total analysis of the correlation between the revealed, Cd, Cu, Hg, Pb and Zn in the residual between the percentage of the amount of content and its wholly showed significant positive correlation. Soil pH-value, and ion exchange for water soluble than the unstable state of the activity of these two states have a significant impact.6. Surface soil heavy metals Cu, Pb, Zn and Cd content and soil pH-value had significant positive correlation between Zn content and soil in which the correlation between pH-value is particularly significant.7. Siping City, most of heavy metals in surface soils at a low single-factor pollution index level of environmental pollution is not serious, only Hg, Cu, Pb, Zn and Cd there are only five potential threat of pollution of heavy metals, but not by the As, Cr pollution However, the contamination of the local regional presence. Nemero comprehensive pollution index is 1.42, the degree of light pollution, including local area there is moderately polluted, no re-contaminated areas. Geological evaluation of the cumulative index with soil heavy metals, Cr no address cumulative pollution threat; As the soil environmental quality is better than 90% of the cumulative area were not contaminated; Cu, Pb and Zn there is more than moderate degree of pollution; Hg there is more serious potential threat of pollution, the region-free clean area.8. Analysised the sources of soil pullution of heavy metals by factor analysis, The heavy metals Cu, Pb and Zn from traffic and transport; Cr derived from natural sources; As and Hg from Coal, garbage burning; Cd human industrial activity is the main product.