沈阳城区交通监测点大气污染特征研究

基于沈阳市2021年交通污染监测点监测的细颗粒物(PM_(2.5))、可吸入颗粒物(PM_(10))、二氧化氮(NO_(2))、一氧化碳(CO)浓度数据,对沈阳市城区交通监测点大气污染特征及变化趋势进行统计分析。结果表明,2021年交通监测点PM_(2.5),PM_(10),NO_(2),CO浓度均高于全市水平,NO_(2)年均浓度超过全市均值幅度最大。PM_(2.5),PM_(10),CO浓度季节变化特征夏季均为最低,冬季相对最高;NO_(2)浓度秋冬春三季整体差异不大。NO_(2)浓度呈明显的早晚高峰变化趋势,且晚间峰值明显高于早高峰时段;PM_(2.5),PM_(10)浓度在09:00—10:00达到上午峰值,22:00—23:00达到晚间峰值;CO浓度日均值与全市差距不大。交通监测点各监测项目存在显著的“周末效应”。NO_(2),CO与机动车流量变化趋势较为一致,PM_(10)浓度数据略滞后于车流量数据。

Based on the online data of PM_(2.5),PM_(10),NO_(2),CO concentration monitored by traffic monitoring stations in Shenyang in 2021,the characteristics and variation trend of air pollution in urban traffic monitoring stations were analyzed.The results showed that the average concentrations of PM_(2.5),PM_(10),NO_(2),CO at traffic monitoring stations were all higher than the city average in 2021,and the average concentration of NO_(2) exceeded the city average by the largest margin.The seasonal variation characteristics of PM_(2.5),PM_(10) and CO concentration showed that the concentration was the lowest in summer and the highest in winter;and there was no significant difference in NO_(2) concentration in autumn,winter and spring.The concentration of NO_(2) showed an obvious trend of morning and evening peak,and the evening peak was significantly higher than the morning peak;the concentration of PM_(2.5) and PM_(10) reached the morning peak between 9:00—10:00 am,and the evening peak between 10:00—11:00 pm;there was little difference between the daily average of CO concentration and the city average.There was a significant"weekend effect"in the monitoring items of traffic monitoring stations.In this study,the variation trend of NO_(2),CO concentration was consistent with the trend of traffic flux,while the trend of PM_(10) concentration was slightly behind the traffic flux.