长春市大气中PM_(10)污染特征分析

Analysis of atmospheric characteristics of PM_(10) pollution in Changchun,China

近年来,大气环境质量的不断恶化受到了人们广泛的关注。利用长春市的食品厂、客车厂、邮电学院、儿童公园、净月潭以及甩湾子等6个自动监测中心提供的2011年PM10、SO2与NO2小时质量浓度的连续监测数据,分析了长春市PM10质量浓度(MPM)的时空分布特征、不同污染物之间的相关性及其形成的原因。结果表明:从空间分布上看,6个采样点的MPM从高到低依次为食品厂>儿童公园>邮电学院>客车厂>净月潭>甩湾子,其中除食品厂与儿童公园外均符合《环境空气质量标准》GB3095-1996的二级标准。从时间分布上看,绝大多数监测点位的冬季MPM是最高的,春季次之,主要是因为冬季采暖与春季沙尘天气,而夏季的MPM最低,主要是湿沉降作用所致。MPM逐日变化呈现出双峰双谷型分布,第一个峰值出现在早上7:00左右,其中最大值出现在5月份的早7:00左右,达到了0.223 mg·m-3,第1个峰值过后呈下降趋势,下午出现质量浓度低谷,其中最小值出现在11月份15:00左右,为0.036 mg·m-3,直到傍晚时缓慢回升,22:00左右达到第2个峰值。通过统计分析不同污染物之间的相关系数,得出PM10与NO2质量浓度的相关性显著,且较稳定,其原因可能是常年排放的机动车尾气尘影响较大,而PM10与SO2质量浓度的相关性不太稳定,这可能是冬季采暖排放的燃煤尘所致。

In recent years, the worsening of atmospheric environmental quality has received widespread attention. In this study, based on continuous hourly data of PM10, SO2 and NO2 which offered by 6 automatic monitoring stations in Changchun, special distribution of PM10, correlations between different pollutants and formation reasons were analyzed. The six automatic monitoring stations include Food Factory, Passenger Car Manufactory, Post and Telecommunications College, Children Park, Jingyue Tan and Shuaiwanzi. The results shown that, special distribution of MPM in six sampling sites from high to low were Food Factory〉 Children Park〉 Post and Telecommunications College 〉 Passenger Car Manufactory 〉 Jingyue Tan 〉 Shuaiwanzi, and except for Food Factory and Children Park, other sampling sites all meet the second standards of the ＂Ambient Air Quality standards＂ GB3095-1996. Time distribution of MPM in most sampling sites were highest in winter, followed by spring, and this was caused by heating in winter and dust in spring. While the minimum MPM occurring in summer was due to wet deposition. Daily variation of MPM showed double peak valley type distribution, and the first peak was at about 7：00 in the morning, in which the maximum occurred at around 7：00 in May, reaching 0.223 mg·m-3. After the first peak, MPM began to decrease, and in the afternoon appeared the lowest concentration, and the minimum （0.036 mg·m-3） occurred at around 15：00 in November. Slow increasing happened from evening, at around 22：00 to reach the second peak. Correlation coefficients between different pollutants were calculated, and the result shown that PM10 and NO2 were significantly correlated, and quite stable, which may be due to the perennial influence of motor vehicle exhaust. However, correlation between SO2 and PM10 were not stable, which may be coal dust caused by heating in winter.