Characteristics And Assessment Of Pollution In Soil Near The Typical Industry Area In Fuzhou

Urban soil is one of the main components of urban ecological environment, which has a very important ecological, environmental and economic function, and meanwhile, it is the sources and sinks of pollutants. With the development of industry and urbanization, the quality of urban soil environment has becoming more and more serious, which directly or indirectly affect the quality of the urban environment and human health. Further more, the urban population density is much more higher than the other area,and it is suffered chronic and intensive disturb from human actions. So it is very important to research on heavy metal concentration and pollution assessment in urban soil.The samples located in Jinshan Pushang Development District, Jinchen Development District, Fuxin Development District, Qinkou IndustriaI Area and Fuzhou No.2 Chemical Area in Fuzhou. Ten surface soil samples were collected from the plots. Which were analyzed for concentrations of Ni, Cd, Pb, Zn, Ph index, invertase, urease, catalase and soil carbon pool. The results of statistical analysis indicated that Qinkou IndustriaI Area's soil was acid with the lowest Ph(6.767), Fuzhou No.2 Chemical Area and Jinshan Pushang Development District's soil was alkali with the highest Ph, and the Jinchen Development District and Fuxin Development District's soil was near to neutral. Jinshan Pushang Development District and Qinkou IndustriaI Area's soil enzyme activity were higher than the other areas. Soil organic carbon in each areas were ordered as the follow: Jinshan Pushang Development District > Jinchen Development District > Fuxin Development District > Qinkou IndustriaI Area > Fuzhou No.2 Chemical Area.The five heavy metal (Ni,Cd,Mn,Pb,Zn) concentrations were respectively 1.779, 4.556, 7.797, 2.741 and 1.370 times of that of background levels in Fuzhou. Among the five heavy metal, the four heavy metal(Ni,Cd,Pb,Zn) were respectively 0.400,0.246,0.273 and 0.378 times of that of the second grade for heavymetals in Environmental Quality Standards for Soils (GB 15618 - 1995) issued by China EPA. Ni,Pb tent to be concentrated in the surface horizon , while the Mn , Cd and Zn content tent to be concentrated in the sub-surface layer.The characteristics of heavy metal concentration and spatial distribution in urban soils were investigated by collecting soil samples around the South-East Motors. The results showed that the heavy metals concentration in the soil went down with the distance between the samples and the company. As regarding the aspect of heavy metals distribution in the studied area, heavy metals concentration was greater in the region from the northwest to the southeast but deceased in the region by the east and the south, the maximum in the area lying in the northwest. The spatial distribution characteristics of 4 heavy metals(Ni,Cd,Pb,Zn)in the sediments of the South-East Motors were studied using geostatisties method. The results showed that all of the heavy metals being studied have good spatial structures,and their variograms could be fitted by spherical models with exponential,Most of the ranges of variograms are around 3 km,which are consistent with average distances among patches with the same feature in the distribution maps. The characteristics of the heavy metal contents were described and the heavy metal pollution assessment results were compared in terms of different assessment guidelines and methods. The results indicated that the soil environment quality in Fuzhou was good as a whole and only Mn contents being greater than guide values (2nd level) of Soil Environmental Quality Standard of China. The pollutions were ordered by general pollution index as follows: Jinchen Development District > Qinkou IndustriaI Area >Jinshan Pushang Development District > Fuxin Development District > Fuzhou No.2 Chemical Area. In different districts, contribution rate of Mn were the most largest, while the rate of Cd and Pb were the most smallest. Potential ecological risk index and pollution classes were investgated as well in this paper. It showed that the soil in the studied area was lightly polluted, the heavy metal pollution degree can be ordered as follow: Mn > Ni> Zn > Cd >Pb. The potential ecological risk index was 14.935, it also showed that the soil in the studied area was lightly polluted.Combining the current study situation with the developing trends in the field, it forwarded two factores that should be studied in the future. Which were the theory and method of health risk assessment in soil of industrial area, and the loss risk of values in polluted land.