| 摘要: |
| 日益严重的大气污染问题不仅对西安市的城市形象，还对人们的身体健康造成危害。对西安市13个国控环境空气质量自动监测站6类污染物的数据进行时空变化特征分析，对各污染物的相关性进行分析，并探讨大气污染原因，结果表明：2010—2018年SO2浓度显著降低，PM10和NO2年均浓度总体并未呈现下降趋势，2013—2018年PM2.5浓度变化趋势与PM10浓度变化趋势相同，二者污染情况均较严重，CO浓度呈减小趋势，2013—2016年O3的污染状况有恶化趋势；第二、三产业增加值的大幅上升所反映的工业、旅游业、交通运输、餐饮业的大规模发展，对西安空气质量有较大影响；SO2的工业减排对大气SO2浓度水平下降效果明显，但NOx和烟（粉）尘排放量的下降却没有反映在大气NO2和颗粒物浓度下降上。说明大气NO2来源除了工业来源外，还有其他重要来源（如：机动车排放、天然气燃烧产物），同时也反映了大气颗粒物来源的复杂，单纯依靠降低烟（粉）尘排放量无法有效降低颗粒物浓度。高增速的机动车保有量和能源消费结构均对西安市大气污染问题有重要影响。 |
| 关键词: 大气污染物 时空分布 污染原因分析 |
| DOI：10.7515/JEE192018 |
| CSTR：32259.14.JEE192018 |
| 分类号: |
| 基金项目:国家自然科学基金项目（41877308） |
| 英文基金项目:National Natural Science Foundation of China (41877308) |
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| Characteristics of variations of atmospheric pollutants over Xi’an during 2010 — 2018 |
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WANG Yelin, CHENG Yan, YAN Lu, LIU Shuting, YAN Mengyuan
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School of Human Settlements and Civil Engineering, Xi’an Jiaotong University, Xi’an 710049, China
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| Abstract: |
| Background, aim, and scope With the development of economy, the problem of air pollution is becoming more and more acute. Because of its special terrain and more anthropogenic emission activities, Xi’an has become one of the most polluted cities, seriously affecting its tourism development and the image of an international metropolis. In addition, air pollution also causes harm to people’s health. The goals of this study are (1) to investigate the variation of atmospheric pollutants; (2) to analyse of the correlation of various pollutants; (3) to identify the causes of air pollution. This work provides reference for air pollution prevention and control in Xi’an. Materials and methods The concentration of atmospheric pollutants in Xi’an were monitored at 13 monitoring stations, from January 1, 2010 to December 31, 2018. We discussed the temporal and spatial variation of atmospheric pollutants, and made correlation analysis of various pollutants. Results The annual concentration of SO2 decreased significantly during 2010—2018, but the annual concentration of PM10 and NO2 did not show a downward trend. The change trend of PM2.5 annual concentration during 2013—2018 was the same as that of PM10. The pollution situation of PM2.5 and PM10 were both serious, the CO annual concentration showed a downward trend, and the pollution situation of O3 from 2013 to 2016 showed a deteriorating trend. Discussion The annual change of pollutant concentration is related to a series of “pollution control and haze reduction” work in Xi’an. The reduction of SO2 concentration is related to the work of “coal-fired boiler disassembly” since 2013. However, the problem of NO2 pollution has not improved because the promotion of “coal to gas” work effectively reduces SO2 concentration, while the combustion of natural gas produces more nitrogen oxides. The decrease of CO concentration reflects that the promotion of clean energy for automobiles and public transport in Xi’an has been more effective in recent years. The deterioration of ozone pollution is mainly related to the increase of volatile organic pollutants (VOCs) and nitrogen oxides emissions. The concentration of PM2.5 and PM10 is restricted by many factors. It is necessary to coordinate the treatment of various pollution factors in order to alleviate PM2.5 and PM10 pollution. Conclusions The large-scale development of industry, tourism, transportation and catering industry has great influence on air quality in Xi’an. Industrial emission reduction of SO2 has a significant effect on the reduction of SO2 concentration in the atmosphere, but the decrease of NOx and dust emission is not reflected in the decrease of NO2 and particulate matter concentration in the atmosphere. It shows that besides industrial sources, there are other important sources of atmospheric NO2 (such as vehicle emissions and natural gas combustion products). What’s more, it reflects the complexity of the sources of atmospheric particulate matter. Reducing the emissions of smoke (powder) dust alone cannot effectively reduce the concentration of particulate matter. High increment speed of motor vehicle ownership and energy consumption structure have an important impact on air pollution in Xi’an. Recommendations and perspectives The results indicate that further reduction of motor vehicle emissions and change of energy consumption structure must have an important impact on alleviating air pollution in Xi’an. |
| Key words: atmospheric pollutants spatial and temporal distribution analysis of pollution causes |
