成都平原农田大气降尘重金属含量特征分析

Characteristics Analysis of Heavy Metals in Atmospheric Dust of Farmland in Chengdu Plain

为探究大气降尘中重金属污染程度,在成都平原某农田区及周边设置51个采样点采集大气降尘,分析降尘重金属含量。结果表明:研究区大气降尘重金属含量均高于土壤背景值;As、Cd、Cr、Cu、Hg、Ni、Pb、Zn重金属含量的变异程度大,空间分布不均匀;根据元素富集特征分析发现,各重金属均受人为活动影响,但程度不同。其中:Cd元素富集呈显著污染,受人为活动影响剧烈;重金属元素Cu、Pb、As为一类,主要受工厂冶炼和交通活动影响;Cd、Hg、Zn各为一类,主要受工业、交通活动以及燃煤影响。

In order to evaluate the contamination of heavy metals from atmospheric deposition in Chongzhou city,Sichuan province,51 samples of atmospheric dust were collected and analyzed.The results showed that the content of heavy metals were higher than ones in soil.The content of As,Cd,Cr,Cu,Hg,Ni,Pb,Zn had a large degree of variation and uneven distribution in space.According to analysis,all heavy metals were mainly controlled by human factors,especially Cd showed high contamination and affected by human activities severely.Cu,Pb,As fall into one category,and their contents mainly originated from factory and traffic emission.Cd,Hg,Zn can be divided into three different categories,the contents of which mainly originated from industrial emission,traffic emission and coal combustion.