城市街道灰尘与大气细颗粒物(PM_(2.5))元素组成特征分析  

Comparison of elemental composition in urban street dust and fine atmospheric particulate matter( PM_(2.5))

作　　者：李法云[1,2] 巴晓博 廖磊[2] 范志平[1] 张营[2] 鞠文鹏 

机构地区：[1]辽宁石油化工大学生态环境研究院,辽宁抚顺113001 [2]辽宁大学环境学院,辽宁沈阳110036 [3]辽宁省抚顺市林业科学研究所,辽宁抚顺113008

出　　处：《气象与环境学报》2015年第5期93-98,共6页Journal of Meteorology and Environment

基　　金：国家自然科学基金(41071317);辽宁省博士科研启动基金(201501131);辽宁大学青年科研基金项目(2012LDQN12)共同资助

摘　　要：利用北京、上海、兰州、香港和南京5个城市街道灰尘与大气细颗粒物(PM2.5)中各元素的含量,比较分析不同城市街道灰尘与PM2.5的元素组成特征,并利用对数浓度图和分歧系数法探究两者元素组成的差异及其与人为源元素的相关性。结果表明:5个城市街道灰尘和PM2.5中,元素Fe、Al、Ca、K、Na占绝大部分(街道灰尘约占97.48%,PM2.5约占90.11%),元素Ti、Mn、Zn、Pb、Cu、Cr和Ni仅占较小的比例(街道灰尘约占2.51%,PM2.5约占9.60%),元素As和Cd含量则更少(街道灰尘约占0.01%,PM2.5约占0.29%)。5个城市街道灰尘与PM2.5元素组成的分歧系数为0.627—0.801之间,平均值为0.711,处于较高水平,即城市街道灰尘与PM2.5的元素组成存在较大差异。人为源元素(Zn、Pb、Cu、Ni、As、Cd、Mn、K、Cr)在PM2.5中的富集程度高于街道灰尘,城市街道灰尘和PM2.5中人为源元素含量的相关性也较大(r=0.783,P<0.01)。Al、Ti、Ca、Fe等典型的地壳元素中,仅Ti元素在街道灰尘中富集,Al、Ca和Fe元素有时富集在街道灰尘中,有时富集在PM2.5中,其含量也未呈明显相关。此外,内陆城市的Na元素在街道灰尘中富集,沿海城市的Na元素则多在PM2.5中富集。Data sets of elements content in urban street dust and PM2. 5from Beijing,Shanghai,Lanzhou,Hong Kong,and Nanjing were collected and filed for analyzing the characteristics of elemental composition of urban street dust and PM2. 5. A log-log concentration diagram was applied to comparison of urban street dust and PM2. 5elemental composition,and coefficient of divergence（ CD） was used to characterize the difference. The results showthat Fe,Al,Ca,K,Na constitute most of the involved elements in both urban street dust and PM2. 5（ street dust： 97. 48%,PM2. 5： 90. 11%）,and Ti,Mn,Zn,Pb,Cu,Cr,Ni only account for a small proportion（ street dust：2. 51%,PM2. 5： 9. 60%）,while As and Cd are scarce（ street dust： 0. 01%,PM2. 5： 0. 29%）; that CDs of urban street dust and PM2. 5elemental compositions maintain a high level ranging from 0. 627 to 0. 801,and the average is0. 711,which means that there is obvious difference between elemental compositions of street dust and PM2. 5in the same city. Enrichment of human-related elements（ Zn,Pb,Cu,Ni,As,Cd,Mn,K,Cr） is higher in PM2. 5than in urban street dust,while both correlation is significant（ r = 0. 783,P 0. 01）. Among crust-related elements such as Al,Ti,Ca and Fe,only Ti is enriched in street dust,while others are either enriched in street dust or in PM2. 5,and no evident correlation is found between these elements in urban street dust and its counterparts in PM2. 5. In addition,Na is enriched in street dust of inland cities,while it is enriched in PM2. 5of coastal cities.

关 键 词：街道灰尘 PM2.5 元素组成 浓度图 分歧系数 

分 类 号：X506[环境科学与工程—环境工程]