武汉市道路尘埃污染中磁学指标与重金属含量对比  

Comparative of magnetism parameters and heavy metals content of street dust pollution-in Wuhan

作　　者：郭高山 李永涛[3] 

机构地区：[1]中国科学院地质与地球物理研究所,北京100029 [2]中国科学院大学,北京100049 [3]中国地质大学地球物理与空间信息学院,湖北武汉430074

出　　处：《中国环境科学》2017年第3期868-877,共10页China Environmental Science

基　　金：国家自然科学基金项目(41572153);湖北省科技支撑计划资助项目(2015BCE077)

摘　　要：对武汉市不同功能区的道路尘埃进行环境磁学和化学分析的综合研究.结果显示:尘埃中的磁性矿物含量在空间分布上具有较大的差异,平均磁化率为工业区(7.36×10^(-6)m^3/kg)>交通沿线(5.38×10^(-6)m^3/kg)>商业区(3.76×10^(-6)m^3/kg)>开发区(2.26×10^(-6)m^3/kg)和风景区(2.48×10^(-6)m^3/kg).工业活动和交通因素是造成区域尘埃中磁性矿物含量升高的主要原因,地理位置和人口密度对尘埃中磁性矿物的含量也有一定的影响.岩石磁学研究结果表明:尘埃中的磁性载体以亚铁磁性矿物为主,部分样品中含有不完整反铁磁性矿物.扫描电镜和能谱分析显示:人类活动产生的磁性颗粒(铁的氧化物和铁的硅铝酸盐)一般呈球形,自然成土过程中形成的不规则状磁性颗粒(磁赤铁矿).污染负荷指数与磁化率(R^2=0.870)、饱和等温剩磁(R^2=0.665)等表征磁性矿物含量的参数呈显著正相关.因此,尘埃的磁学参数可以作为重金属含量的参考指标.A systematic study of street dust in Wuhan city, china, was carried out using combined environmental magnetism and geochemistry techniques. Magnetic measurement showed that magnetic minerals of street dust have distinct differences in spatial distribution pattern and overall values of magnetic susceptibility in the following sequence： industrial area（χ=7.36×10^-6m3/kg）〉 traffic route（χ=5.38×10^-6m3/kg）〉 business district（χ=3.76×10^-6m3/kg） 〉development（χ=2.26×10^-6m3/kg） and scenic areas（χ=2.48×10^-6m3/kg）. The results indicated that the content of magnetic minerals in the street dust mainly attributed to the industrial production and transportation factors, while the distribution of population density also had definite influence on the content of magnetic minerals. Rock magnetic measurements demonstrated that dominant magnetic components were ferrimagnetic minerals, as well as antiferromagnetic minerals. SEM/EDX analysis revealed that there were some spherical Fe-containing particles from anthropogenic activity, which was different from pedogenic ferromagnetic minerals in nature soil. The PLI showed significant correlation with the mean value of χ（R2=0.870） and SIRM（R2=0.665）, which meant magnetism parameters of street dust could be seen as an indicator of heavy metals pollution.

关 键 词：环境磁学 重金属分析 环境污染 街道尘埃 武汉市 

分 类 号：X51[环境科学与工程—环境工程]