The Distribution Features And Research Of Heavy Metals In Atmospheric Particulate Matter And Soil In Yan Ji

Heavy metals are one group of the typical environmental pollutants.It has a wide range of pollution,long time of duration,and is not easy to decompose in the environment.It can be accumulated through the various consumers in the food chain of ecosystem.The distribution of heavy metals in different environmental media is different.In the atmosphere,heavy metals are mainly adsorbed on the surface of air particulates and transferred into the soil and water through dry and wet deposition.In this study,we evaluated the distributions,sources and potential ecological risks of heavy metal elements in air particulates and soil in Yanji city.Samples of air particulates were collected by high volume air sampler of analyzed for 16 heavy metals using inductively coupled plasma mass spectrometer.Potential sources of heavy metals were evaluated using enrichment factor analysis(EFA),correlation analysis and principal component analysis(PCA).The results showed that the concentrations of heavy metals in air particulates were Zn>Ba>Mn>Pb>As>Cu>Cr>Ni>V>Sb>Co>Cd>T1>Mo = Se = Ag.Among them,the harmful heavy metal elements with high concentrations were Pb,As,Cu and Cr,and the concentrations of As and Cr exceeded the national ambient air quality standard.Elevated concentrations of Pb,Sb,Se,Cd,Tl and Ag in air particulates were observed in heating period.Results of EFA and PCA analysis showed that the main sources of air particulates were fuel combustion,road dust and automobile exhaust.Potential ecological harm index(PEHI)of air particulates is up to 216916,indicating a strong level of potential ecological harm.Concentrations of heavy metals in soil were Ba>Mn>Zn>As>Ni>V>Cu>Cr>Pb>Co>Sb>TI>Cd>Se = Mo = Ag.Concentrations of heavy metals in soil of commercial-residential areas and industrial areas are Mn>Ba>Zn,and those in suburban areas are Ba>Mn>Zn.EFA and PCA analysis showed that the main sources of heavy metals in soil were natural sources,automobile exhaust and metallurgical industrial sources.Ecological risk analysis showed that the PEHI of heavy metals in the soil was 52772,which belonged to the very strong ecological hazard level.The main contributions were from As,Cu,Ni,Co,Cd,Pb,Zn,Cr and V in the soil,especially those of As are higher than other heavy metals.The results of this study can provide scientific basis and basic data for the protection and construction of regional ecological environment,which has important practical significance.