阜新市主城区降尘中有机污染物来源分析

Source Analysis of Organic Pollutants in the Dustfall from the Main Urban Areas of Fuxin City

文章采用GC-MS联用系统对辽西阜新市主城区的9个大气降尘中一种生物标志物——正构烷烃的组成进行了测定,分析了各样点降尘中正构烷烃组成特征并探讨了其指示的区域污染源信息。结果表明,阜新市大气降尘中正构烷烃主要存在低碳组分无奇偶优势而高碳数组分奇偶优势显著的双峰型、高碳组分有奇偶优势的后峰型和低碳组分无奇偶优势的前峰型3种分布形式; CPI(奇偶优势)、L/H(低碳/高碳)和ACL(平均碳链长度)指数分析表明阜新市降尘中正构烷烃贡献的高碳数部分来源于城市绿化的高等陆生植物,而低碳数部分来源于化石燃料残余。此外,研究中发现大部分样点降尘特性指示的污染源效应较统一,总体受大气状况主导而与空间位置关系不大。

In this paper,GC-MS was used to detect the composition of n-alkanes,a biomarker in the dustfall from the main urban areas of Fuxin City located in the west of Liaoning Province.Composition characteristics of n-alkanes in the dustfall at each sampling point were analyzed and the indicating regional pollution sources were discussed.The results showed that there were three composition styles for n-alkanes from the dustfall in Fuxin including the bimodal shape with an OEP（odd-even predominance） only in higher carbon n-alkanes,the post-peak unimodal shape with OEP in high carbon n-alkanes,and the front-peak unimodal shape without OEP in low carbon n-alkanes.CPI（carbon preference index） proxies（including CPI1 and CPI2）,L/H（low carbon/ high carbon） and ACL（average chain length） analysis results indicated that high carbon n-alkanes was contributed from the high terrestrial plants for city afforestation,while low carbon n-alkanes was resulted from utilization of fossil fuel.Additionally,it was found that most of the samples had the similar effects of pollution source indication via n-alkanes proxy statistics,which was dominated by atmosphere condition but less related to the spatial position.