State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
Environ Sci Technol. 2013 Sep 17;47(18):10454-61. doi: 10.1021/es401250k. Epub 2013 Sep 4.
Samples of fine particulate matter (PM2.5) were collected during July 2009 to March 2010 at a regional background site in East China. The mass concentrations of organic carbon (OC) and elemental carbon (EC) were characterized by the highest levels in winter (December to February) and the lowest abundances in summer (June to August). Conversely, the concentrations of levoglucosan were higher in summer than in winter. The observations were associated to the anthropogenic air pollutions (predominantly fossil-fuel combustions) transport from the center and north China with the northwest winds in winter and large contribution of the open biomass burning activities in South China and East China in summer, which was evident by air-mass trajectories and MODIS satellite fire counts. To assign fossil and nonfossil contributions of carbonaceous matters, the radiocarbon contents in water-insoluble OC (WINSOC) and EC in 4 combined samples representing four seasons were analyzed using the isolation system established in China. The results indicated that biomass burning and biogenic sources (59%) were the major contribution to the WINSOC, whereas fossil fuel (78%) was the dominant contributor to the refractory EC at this site. The source variation obtained by radiocarbon was consistent with other indicators, such as the OC/EC ratios and the levoglucosan concentration. Biomass burning and biogenic emissions were found to predominate in the summer and autumn, whereas fossil fuel emissions predominate in winter and spring.
于 2009 年 7 月至 2010 年 3 月在华东地区的一个区域背景站点采集了细颗粒物（PM2.5）样本。有机碳（OC）和元素碳（EC）的质量浓度在冬季（12 月至 2 月）最高，夏季（6 月至 8 月）最低。相反，左旋葡聚糖的浓度在夏季高于冬季。这些观测结果与冬季西北风从华北和中心地带传输的人为空气污染（主要是化石燃料燃烧）以及夏季华南和华东地区的大规模生物质燃烧活动有关，这一点通过大气轨迹和 MODIS 卫星火灾计数得到了证实。为了分配碳质物质的化石和非化石贡献，使用中国建立的分离系统分析了代表四个季节的 4 个组合样品中的水不溶性 OC（WINSOC）和 EC 中的放射性碳含量。结果表明，生物质燃烧和生物源（59%）是 WINSOC 的主要贡献者，而在该站点，化石燃料（78%）是难熔 EC 的主要贡献者。放射性碳获得的来源变化与其他指标一致，如 OC/EC 比值和左旋葡聚糖浓度。在夏季和秋季发现生物质燃烧和生物排放占主导地位，而在冬季和春季则以化石燃料排放为主。
