| 摘要: |
| 随着我国工业化、城市化和机动化的高速发展，大气环境质量越来越受民众关注，我国已建成国控—省控—市控—县控四级环境空气自动监测网络，监测项目包括SO2、O2、CO、O3、PM2.5和PM10。基于2018年绵阳市环境空气监测数据、颗粒物化学组分及气象资料分析上述6个监测项目年均、季度、月均、日均及每日最大小时浓度变化特征，并进一步探讨污染物浓度与气象条件的相关性，结合颗粒物化学组分对产生原因进行剖析。结果表明：绵阳市冬季环境空气质量较差，夏季相对较好。Pearson相关性分析表明：SO2、NO2、CO和颗粒物（PM2和PM10）之间存在显著相关性，冬季PM2.5与SO2、NO2的相关性系数分别为0.610和0.635，PM10与SO2、NO2的相关性系数分别为0.655和0.655，颗粒物主要化学组分为硫酸盐、硝酸盐、铵盐和二次有机气溶胶，颗粒物二次转化尤为明显，冬季需重点管控颗粒物；春季和夏季O3与PM2.5、PM10呈显著性正相关，需做好颗粒物和O2的协同管控。O3每日最大小时浓度多集中在13∶00—18∶00，其他污染物每日最大小时浓度多集中于08∶00—12∶00和20∶00—24∶00，同时NO2在20∶00—24∶00出现每日最大小时浓度的频次占67.1%，控制机动车等污染源排放尤为重要。 |
| 关键词: 绵阳市 环境空气质量 气象条件 相关性分析 |
| DOI：10.7515/JEE202020 |
| CSTR： |
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| 基金项目:教育部产学合作协同育人项目（201801275004，201901098058） |
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| Variation concentration characteristics and correlations of atmospheric contaminant in Mianyang |
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DU Juan, SONG Pengcheng, LONG Ping, HUANG Qiang, QIAO Junxi
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1. City College, Southwest University of Science and Technology, Mianyang 621010, China
2. Mianyang Environmental Monitoring Central Station, Mianyang 621010, China
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| Abstract: |
| Background, aim, and scope With the rapid development of industrialization, urbanization and motorization in our country, ambient air quality has attracted more and more attention for the public. China has established a four-level (national, provincial, municipal, and county level) automatic monitoring networks for ambient air. The primary monitoring items of this system are SO2, NO2, CO, O3, PM2.5 and PM10. Mianyang is located in the northwest of the Sichuan Basin, according to the ambient air quality standards (GB 3095—2012), the annual mean concentration of PM2.5 exceeds the Grade Ⅱ standard (35 μg·m−3). To fully understand ambient air quality of Mianyang City, more characteristics of air pollutants should be considered. Materials and methods Based on the ambient air monitoring data, chemical composition of particulate matter and meteorological data of Mianyang City in 2018, the variation characteristics of six parameters including annual average, quarterly average, monthly average, daily average and hourly maximum for daily value were investigated. Besides, the correlation between pollutant concentration and meteorological conditions was further discussed, and in combination with the chemical composition of particulate matter, the causes of air pollution were analyzed. Results The results showed that the SO2 level in Mianyang City is relatively low. Compared with the autumn and summer, the level of particulate matter (PM) is on higher level in the spring and winter. Additionally, the level of O3 is high in spring and summer, while in autumn and winter it appears low. Discussion After calculated the Pearson correlation coefficient, the correlation coefficients of PM2.5 and SO2, NO2 in winter are 0.610 and 0.635, respectively. The correlation coefficients of PM10 and SO2, NO2 are 0.655 and 0.655, respectively. These data indicate that there is a significant correlation between SO2, NO2, CO and particulate matters (PM2.5 and PM10). Besides, the main chemical composition of particulate matter is sulfate, nitrate, ammonium salt and the secondary organic aerosol, indicating that it is necessary to focus on controlling the generation of particulate matter in winter. In spring and summer, there is a significant positive correlation between O3 and PM2.5 and PM10, which indicates that PM and O3 need to be controlled in coordination. Hourly maximum concentration in daily of O3 is mostly concentrated at 13∶00—18∶00. However, other pollutants is mostly concentrated at 08∶00—12∶00 and 20∶00—24∶00. Besides, the frequency of NO2 appearing between 20∶00 and 24∶00 is 67.1%. Therefore, it is especially important to control the emission of pollution sources such as motor vehicles in the later period. Conclusions Overall, air quality of Mianyang is good. However, the ambient air quality is poor in winter and relatively good in summer. Recommendations and perspectives This article mainly analyzes the ambient air quality of Mianyang City and the correlation between pollutants, and puts forward the corresponding solutions to reducing the air pollution, hoping to give public some enlightenment. |
| Key words: Mianyang City ambient air quality meteorological conditions correlations analysis |
