中文摘要：

[目的]研究西安市长途汽车站地表灰尘中重金属的主要成分、可能来源及其污染水平,为改善汽车站内及周边环境现状提供科学依据。[方法]利用X-Ray荧光光谱仪对西安市内20个具有代表性的汽车站地表灰尘中Cu,Mn,Ni,Pb,V和Zn的元素含量进行分析,采用地积累指数法及潜在生态风险指数法评价灰尘重金属的污染水平及环境风险,利用主成分分析。聚类分析等方法来研究城市汽车站地表灰尘中重金属的主要成分及其可能来源。[结果]Cu,Pb,Zn均在不同程度上超过陕西省土壤背景值,其含量的平均值分别为36.3,107.7,113.5mg/kg。地积累指数法评价表明,除Pb为中度污染以外,其余元素均为无污染;潜在生态风险指数法表明,西安汽车站地表灰尘中的重金属元素处于中等污染水平,具有中等潜在生态风险。[结论]Cu,Mn和Ni主要来自于自然源和交通源,Pb和Zn主要来自汽车尾气的排放及零部件的磨损,V则主要来自于自然源。

英文摘要：

[Objective]The objective of the study is to investigate heavy metal pollution and possible sources of heavy metals in surface dust in coach stations of Xi＇an City,in order to provide support for improving the environment in coach stations of Xi＇an City.[Methods]Dust samples were collected from 20 representative coach stations in Xi＇an City and the concentrations of Cu,Mn,Ni,Pb,V,and Zn were measured by X-Ray fluorescence spectroscopy.Pollution level and environmental risk of heavy metals in the dust were assessed using the geo-accumulation pollution index and the potentially ecological risk index,respectively.Correlation coefficient analysis,principal component analysis and cluster analysis were used to identify the possible sources of these heavy metals.[Results]The mean content of Cu,Pb and Zn in the dust was 36.3,107.7and 113.5 mg/kg,respectively,which were significantly higher than their background values in soil in Shaanxi.The geo-accumulation index results indicated that the pollution level of Pb was medium,while other heavy metal pollution belonged to low-level.The potentially ecological risk index showed that the surface dust from coach stations was moderately polluted,and have medium ecological risk.[Conclusion]Source identification results suggest that Cu,Mn and Ni in the surface dust mainly came from nature and traffic,Pb and Zn mainly came from automobile exhaust emissions and worn-out parts,and V mainly came from the nature.