In this study, the ionic and carbonaceous compounds in PM_2.5 were analysed in the small residential city of Chuncheon, Korea. To identify the local sources that substantially influence PM_2.5 concentrations, the samples were divided into two groups: samples with PM_2.5 concentrations higher than those in the upwind metropolitan area (Seoul) and samples with lower PM_2.5 concentrations. During the sampling period (December 2016–August 2018), the average PM_2.5 was 23.2 μg m⁻³, which exceeds the annual national ambient air quality standard (15 μg m⁻³). When the PM_2.5 concentrations were higher in Chuncheon than in Seoul, the organic carbon (OC) and elemental carbon (EC) concentrations increased the most among all the PM_2.5 components measured in this study. This is attributable to secondary formation and biomass burning, because secondary OC was enhanced and water soluble OC was strongly correlated with K⁺, EC, and OC. A principal component analysis identified four factors contributing to PM_2.5: fossil-fuel combustion, secondary inorganic and organic reactions in biomass burning plumes, crustal dust, and secondary NH₄⁺ formation.

中文翻译：

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韩国一个小城市本地发生的PM2.5高浓度发作的特征

在这项研究中，分析了韩国春川这个小型居住城市中PM _2.5中的离子和碳质化合物。为了确定对PM _2.5浓度有实质性影响的本地来源，将样品分为两类：PM _2.5浓度高于上风大都市区（首尔）的样品和PM _2.5浓度较低的样品。在采样期间（2016年12月至2018年8月），平均PM _2.5为23.2μgm ^-3，超过了年度国家环境空气质量标准（15μgm ^-3）。当PM _2.5春川市的铅浓度高于首尔，在这项研究中测得的所有PM _2.5成分中，有机碳（OC）和元素碳（EC）的浓度增加最多。这归因于次级形成和生物质燃烧，因为次级OC增强，水溶性OC与K ⁺，EC和OC密切相关。主成分分析确定了造成PM _2.5的四个因素：化石燃料燃烧，生物质燃烧烟羽中的二次无机和有机反应，地壳粉尘和二次NH ₄ ⁺形成。