兰州市街道尘埃的元素空间变化特征研究

用X射线荧光法分析了兰州市街道尘埃样品元素的含量,并利用富集因子分析方法对实验数据进行统计分析,以对比元素浓度的空间变化特征。结果表明:兰州街道尘埃中元素A l,Na,Ba,Si,Ca,Sn,Th,W,La,U,Zr,Zn,Mn,Ce,Hf,Pb,Mo,Cs,C l的富集因子介于1-10之间,人为污染占相当的比例;As,S,B i的富集因子大于10,主要源于人类活动导致的各种污染因素;标识性元素的空间特征分析表明,兰州市燃煤污染较严重的区域为西固区和兰州市第二热电厂附近;沙井驿附近和城关区汽车尾气污染严重;B i和Cs可能来源于工业污染。

Spatial Variation Characteristics of Elements of Street Dust in Lanzhou

amples of street dust were collected in Lanzhou in January 2006 and element concentration were analyzed by X-ray fluorescence.Element concentrations in different places were compared,and enrichment factor method was used in this study.The conclusions are shown as follows.Enrichment factor values of Al,Na,Ba,Si,Ca,Sn,Th,W,La,U,Zr,Zn,Mn,Ce,Hf,Pb,Mo,Cs,Cl are among 1-10.At certain extent,these elements come from artificialfactors.Enrichment factor values ofAs,S,Bi are more than 10.That means they come from man-made pollution.The space characteristics of some representativeelements show that coal buring pollution in Xigu district and the second thermoelectricplant in Lanzhou aremore serious than others.The pollution of vehicular exhaustsin Shajingyi and Chengguan district are higher.At last,Bi and Cs are deduced from industrialpollution.