泉州城市表层土壤中金属元素来源分析

采集了泉州市47个城市表层土壤样,用ICP-MS检测技术,研究了土壤中26种重金属元素的富集特征、环境风险及污染来源。富集因子结果显示,与泉州市土壤背景值相比,Li、Ni、Co、Cu、Zn、Sr、Cd、Sn、Sb、Pb、Ta在城市表层土壤中的富集因子大于1,而Ti、V、Cr、Fe、Mn、Ga、Ge、As、Rb、Y、Nb、Cs、Bi、Th、U的富集因子小于1。从功能区上看,工业区污染最为严重,其次依次为农业区、商住区、城市绿地、交通区。环境风险指数表明,泉州市城市表层土壤中重金属污染具有极高的环境风险,达到极高风险级别的样品占48.9%。采用多元统计分析方法对土壤样品中各金属元素来源进行解析,结果表明,研究区城市表层土壤中金属元素总体可分成5类：①交通运输类（Sn、Pb、Sb、Bi）;②工业因子类（Cr、Co、Ni、Fe、Mn）;③自然因子类别（Ga、Ge、Ti、V、Cu）;④混合因子类别（Zn、Cd、Sr、Th、U、Y、As、Cs、Nb、Ta、Rb）;⑤生活垃圾因子类别（Li）。

Sources of Metals in the Urban Topsoil of Quanzhou City

Forty-seven urban topsoil samples were collected in Quanzhou city and ICP-MS determining technology was applied to study the accumulation characteristics,environmental risk and sources of 26 metals in the urban topsoil.The results of enrichment factors showed that the enrichment factors of Li,Ni,Co,Cu,Zn,Sr,Cd,Sn,Sb,Pb and Ta were higher than 1.0,while those of Ti,V,Cr,Fe,Mn,Ga,Ge,As,Rb,Y,Nb,Cs,Bi,Th and U were lower than 1.0 in the urban topsoil compared with the background values of the soils in Quanzhou city.As for the pollution levels of different functional divisions,industrial area was the most serious,with the following decreasing order: agricultural area > residential and commercial area > green belt > traffic zone.The environmental risk indexes indicated that the pollution of heavy metals in the urban topsoil presented very high environmental risk,with the frequency of samples belonging to the grade of very high environmental risk reaching 48.9%.Multiple statistical analyses suggested that 26 heavy metals studied in the urban topsoil could be classified into five general groups: 1) traffic elements(Sn,Pb,Sb,and Bi);2) industrial elements(Cr,Co,Ni,Fe,and Mn);3) natural elements(Ga,Ge,Ti,V,and Cu);4) elements of mixed origins(Zn,Cd,Sr,Th,U,Y,As,Cs,Nb,Ta,Rb,Ga,Ge,Ti,V,and Cu);and 5) house refuse elements(Li).