为了对长三角地区大气污染进行防治和控制,了解长三角地区大气环境质量变化规律,有必要对其颗粒物的组成及特征进行分析,以揭示其形成机制。采用Partisal-plus2025型连续空气采样机在嘉兴双桥农场(长三角中心)进行采样,利用对采样样品化学分析的结果,分析了PM10、PM2.5的化学组成、质量浓度的分布特征及其相对关系。PM2.5和PM10中19种无机元素质量浓度的总和约占其质量浓度的23%和25%,其中Al、Si、Ca是主要贡献元素;8种水溶性离子质量浓度总和约占PM2.5和PM10质量浓度的51%和43%,其中NO3^-和SO4^2-是主要贡献成分;有机碳的质量浓度约占PM2.5和PM10质量浓度的16.12%和17.43%,元素碳的质量浓度约占PM2.5和PM10质量浓度的16.97%和15.84%,可见该地区存在较严重的二次有机碳污染和元素碳污染。研究结果为揭示大气颗粒物的形成机制和对其污染进行防治和控制提供了基础性的研究数据。
In order to prevent and control the air pollution of the Yangtze River Delta region and understand the variation rule of the air environmental quality in the region, it is necessary to analyze the composition and physical and chemical characteristics of particles in the air,and thus to find out the formation mechanism of the particles. Samples were sampled by Partisal-plus 2025 continuous air sampling machine in Jiaxing Shuangqiao Farm which was located at the center of the Yangtze River Delta, and the chemical composition and the distribution characteristics of quality concentration of PM10 and PM2.5 were analyzed. The proportion of the total quality concentration of 19 kinds of inorganic elements in PM10 and PM2.5 were 23% and 25% with Al,Si,and Ca being the main contributing elements; the quality concentration summation of 8 kinds of water-soluble irons occupied 51% and 43% of that of PM10 and PM2.5 respectively,and NO3 and SOlwere the main contributors in those soluble ions. The quality concentration of organic carbon occupied about 16.12% and 17.43% of that of PM10 and PM2.5, and element carbon occupied 16.97% and 15.84%. Therefore,it can be concluded that the region was seriously polluted by organic carbon and element carbon. The results provided basic research data to reveal the forming mechanism of atmospheric particles and to prevent and control this kind of pollution.