2015年南京市SO_2、NO_2、CO和O_3的污染特征分析

Pollution characteristics of SO_2,NO_2,CO and O_3 in Nanjing in 2015

分析了2015年南京市二氧化硫(SO_2)、二氧化氮(NO_2)、一氧化碳(CO)和臭氧(O_3)的污染特征。南京市SO_2、NO_2、CO和O_3的年均浓度分别为19.3μg·m^(-3)、50.2μg·m^(-3)、0.972 mg·m^(-3)和114μg·m^(-3);SO_2和CO污染相对较轻,NO_2和O_3污染相对严重。SO_2、CO和O_3的日变化呈"单峰型",而NO_2的呈"双峰型";SO_2、NO_2和CO浓度在冬季最高,夏季最低,而O_3相反。秸秆焚烧产物的区域输送在夏收(6月)和秋收(11月)时节对南京市CO的贡献显著。各监测点及全市的气态污染物普遍表现出"反周末效应",指示外来污染源。

This study focused on the pollution characteristics of sulfur dioxide （SO2） , nitrogen dioxide （NO2） , carbon monoxide （CO） , and ozone （O3） in Nanjing for the year 2015. The annual mean concentrations of SO2, NO2, CO, and 03 in Nanjing were 19.3 μg · m^-3, 50.2 μg · m^-3, 0. 972 mg · m-3 , and 114 μg · m^-3 , re- spectively. The pollution levels of both SO2 and CO were relatively low, whereas those of both NO2 and 03 were relatively high. Diurnal variations of SO2 , CO, and O3 showed bimodal distributions, whereas that of NO2 showed unimodal distribution. The concentrations of SO2 , NO2 , and CO were the highest in winter and the lowest in sum- mer, whereas that of 03 was the highest in summer and the lowest in winter. The regional transport of straw com- bustion products contributed greatly to CO concentrations during the summer and autumn harvest periods of 2015 in Nanjing. The gaseous pollutants exhibited an anti-weekend effect in all the monitoring sites of Nanjing, indica- ting external pollution sources.