郑州市金水区冬季大气PM_(2.5)污染特征及来源解析

Pollution characteristics and source apportionment of ambient PM_(2.5) from Jinshui District of Zhengzhou in winter

为探究郑州市金水区冬季PM_(2.5)污染特征及来源贡献,采用离线采样法对金水区大气中银行学校和郑纺机两站点的PM_(2.5)进行了采集,通过颗粒物分析仪解析PM_(2.5)的组分构成,并重点采用正交矩阵因子(PMF)模型和多尺度空气质量(CMAQ)模型分析评估了PM_(2.5)的来源及输送贡献。结果表明,银行学校和郑纺机站点中水溶性离子(WSIIs)浓度分别占PM_(2.5)浓度的46.4%和44.8%,金属元素组分浓度分别占17.2%和14.3%。富集因子(EF)及比值分析显示,两站点需重点关注燃煤源和机动车源的影响。PMF源解析显示,金水区两站点中对PM_(2.5)的浓度贡献污染源主要是机动车源、扬尘源及燃煤源。CMAQ模型模拟结果显示,金水区两站点中PM_(2.5)的主要来自金水区自身的排放,贡献占比高达43%以上,其次为金水区的北部、西部和南部区域。研究显示,在加强本地PM_(2.5)污染管控的同时,需要考虑北部、西部及南部区域以及郑州市周边地区的区域联防联控。

To explore the characteristics and source contribution of PM_(2.5)pollution in winter from Jinshui District of Zhengzhou City,the off-line sample collection method was adopted to collect PM_(2.5)from two sites in Jinshui District,banking school and textile machine factory,and the composition of PM_(2.5)was analyzed by the particulate matter component analysis instrument.Positive matrix factorization(PMF)model and community multi-scale air quality(CMAQ)model were used to analyze the source and transport contribution of PM_(2.5).The research showed that the concentration ratios of water-soluble ions(WSIIs)in bank school and textile machine factory sites were 46.4%and 44.8%of PM_(2.5)concentration,respectively.The concentration ratios of metal elements were 17.2%and 14.3%of PM_(2.5)concentration,respectively.Enrichment factor(EF)and ratio analysis showed that the two sites should pay more attention to the influence of coal source and motor vehicle source.PMF source analysis showed that the main pollution sources contributing to PM_(2.5)concentration in Jinshui District were motor vehicles,dust and coal burning.The CMAQ model analysis showed that PM_(2.5)of the two sites were mainly from the emission contribution of Jinshui District itself,which was as high as 43%,followed by the northern,western and southern regions of Jinshui District.The study showed that while strengthened local PM_(2.5)pollution control,prevention and control of regional joint should be considered in the northern,western and southern regions as well as the surrounding areas of Zhengzhou.