我国PM1浓度、化学组分及来源的时空分布

Temporal and spatial distribution of atmospheric PM_1 concentration,composition and source in China

总结我国京津冀、长三角和珠三角地区不同季节基于气溶胶质谱仪的外场观测研究,探讨我国非难熔性亚微米气溶胶(NR-PM_1)化学组分和来源的时空变化特征。结果表明,3个地区NR-PM_1质量浓度变化范围为15.3~90.5μg/m^3,京津冀浓度最高,珠三角最低;3个地区中有机物均为NR-PM_1的主要组分,占24%~58%;珠三角地区硫酸盐含量更高,硝酸盐含量低;各地区秋冬季NR-PM_1质量浓度高于春夏季,主要是由于燃烧排放的一次有机物(BBOA、CCOA)与无机物(氯化物)增多造成;对有机物源解析的统计发现,机动车源(HOA)与二次源(SOA)在各地区站点中广泛存在,而烹饪源(COA)则一般存在于城市站点;生物质燃烧源(BBOA)在长三角、珠三角地区更为广泛,燃煤源(CCOA)主要存在于京津冀地区。

Field observations based on aerosol mass spectrometers in Beijing-Tianjin-Hebei region, Yangtze River Delta and PearlRiver Delta s were summarized in this study, and the temporal and spatial variation of chemical composition and source of submicron aerosols was discussed. The results show that the average mass concentration of NR-PM1 in the three regions range between 15.3 and 67.9 μg/m^3, the highest is in Beijing-Tianjin-Hebei region and the lowest is in Pearl River Delta. Organic aerosol is the major component of NR-PMt in each region, accounting for 24%-58%. In the Pearl River Delta, the mass fraction of sulfate is significantly higher than that in the other two regions, and that of nitrate is significantly lower. In general, the concentrations of NR-PM1 in autumn and winter are higher than those in spring and summer, mainly due to the increase of organic （BBOA, CCOA） and inorganic （chlorinated） components from combustion emissions. It is also found that HOA and SOA are widespread in all sites of the three regions, while COA is generally found in urban sites. BBOA is widely distributed in Yangtze River Delta and Pearl River Delta, CCOA, however, only existed in Beijing-Tianjin-Hebei region.