南充市城市空气质量变化及达标分析

为了掌握南充市近年来城市空气质量变化及其达标情况，对南充市城区2008～2012年SO2、NO2和PM10的质量浓度数据进行统计分析，并计算各个站点的空气污染指数和空气质量指数。结果表明，3种污染物浓度值都有明显的下降趋势，S02浓度在0．002～0．052mg／m^3之间变化；N02浓度值从0．042mg／m^3下降到0．029mg／m^3；PM10浓度在0．060～0．063mg／m^3之间波动。南充市空气质量冬季较差，夏季较好。在5个监测点中，炼油厂空气质量最差，优良率为92．9％（85．1％）；高坪空气质量最好，优良率为99．1％（98．3％）。相关性分析表明，南充市空气污染源主要是工业燃煤和机动车尾气。

Analysis of Urban Air Quality Variation and the Qualified Rate in Nanchong City

This paper analyzed the mass concentrations of SO2, NO2 and PM10 and calculated the air pollution index and air quality index of the sites of Nanchong City from 2008 to 2012. The result showed that the concentrations of three pollutants presented dramatically descend. The concentrations of SO2 changed between 0. 042mg/m3 and 0. 052mg/m3 , NO2 dropped from 0. 042mg/m3 to 0. 029mg/m3 and PM10 dropped from 0. 060mg/m3 to 0. 063mg/m3. Besides, the air quality in summer was better than that in winter. In the five monitoring sites, the air quality at LY site was the worst, and the excellent rate of air quality was 92. 9% （85. 1% ）, while the GP site was the best and the excellent rate was 99. 1% （98. 3% ）. In addition, the correlative analysis showed that industrial burning coal and motor vehicle exhaust were the major air pollution sources in Nanchong City.