Analysis Of Heavy Metal In Soil And Assessment Of Pollution In A Steel Factory And Its Surrounding Farmland Localed In Southern Shanxi

As the basis material for human survival and development, thesoil not only in the production of plants, but also serves as a carrierof various pollutions. At the same time, the soil ecologicalenvironment has been severly damaged for the unreasonableutilization and management of soil in the production process withthe development of industry and agriculture. Therefore, it hasimportant theoretical and practical significance to investigate theenvironmental quality of soil and puts forward countermeasures.This study survived soil physical and chemical properties, heavymetal contents and magnetic parameters of86surface soil samplesand90profile soil samples which were collected from the steelfactory and the surrounding farmland. Separately anslysis thedistribution relevance and origin of these soil samples’ heavy metalscontent, soil physical and chemical properties and magneticsusceptical value. The Single-factor pollution index method,Nemerow comprehensive pollution index method, Geo-accumulationindex (Igeo) method and the Potential ecological risk index methodwere used for the pollution assessment, and sources of heavy metals in soil samples were also analysed. The main reasons are as follows:(1)The heavy metal contents within the steel factory soilsamples are generally higher than the content of the factorysurrounding farmland soil samples.Although the average content ofCd, Cr, Cu, Mn, Pb, and Zn elements had not exceed the nationalaverage leverals of soil environmental quality standard, but most ofthe content of the samples exceed background value in soilenvironments in Shanxi province, especially the accumulation of Pb.Correlation analysis showed that the complex and significantcorrelation of seven heavy metals within the factory.(2)The magnetic susceptibility of the surface soils had obviousdivergence; some were higher than those of common Cinnamon soil.The spatial distribution for pollution of heavy metals in surface soiland the magnetic susceptibility characteristic indicates that thedistribution range and heavy metal pollution susceptibility have greatrelevance. Both the magnetic susceptibility and heavy metal elementcontents decreased downwards in soil profiles, shaming the samevertical variation tendency. There were extremely significantcorrelations between the magnetic susceptibility and the contents ofPb and Zn, significant correlation between the magneticsusceptibility and the contents of Cu.(3)According to single-factor pollution index method, if thenational soil environmental quality standards to measure, soils in thestudy area in the clean level; and soil belongs to the low level in thestudy area if analysis it by the potential ecological risk index method.Background value of soil in Shanxi province as an evaluationstandard, the single factor pollutionl index shows that each element has a different degree of pollution, especially the accumulation ofPb in particually; Nemerow comprehensive pollution index showsthat the study areas has reached the level of heavy pollution; thegeo-accumulation index shows the result that the soil samples withinthe steel factory are in moderate pollution levels just like the Pb infactory surrounding farmland soil samples, and all seven kinds ofheavy metal elements content exceeds the background value of soilenvironment in Shanxi, the most part of pollution elements was Pband Cr inside the steel factory; soil of the study areas has reached thelevel of moderate hazard if calculated it by the potential ecologicalrisk index.(4)Further Factor Analysis on sources of heavy metals revealedthat Ni、Mn and Cu contamination in the soils were caused by naturalfactors; Pb and Zn were mainly originated from industrial activities;and agricultural activities had the largest impact on the accumulationof Cd and Cr. The findings of sources and the evaluation of surface soilheavy metal contamination can provide a scientific basis forprevention and treatment of the soil environment pollution in thisarea.