中国地铁对线路周边空气的减污效益评估——基于中国地铁段和高分辨率日度污染数据的分析

陈晓红, 刘琨, 蔡思佳, 汪阳洁

系统工程理论与实践 ›› 2025, Vol. 45 ›› Issue (4) : 1224-1244.

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PDF(3375 KB)
系统工程理论与实践 ›› 2025, Vol. 45 ›› Issue (4) : 1224-1244. DOI: 10.12011/SETP2023-2422
论文

中国地铁对线路周边空气的减污效益评估——基于中国地铁段和高分辨率日度污染数据的分析

    陈晓红1,2,3, 刘琨1,3, 蔡思佳4, 汪阳洁2
作者信息 +

Assessment of air pollution reduction benefits by Chinese metro systems along their routes—Analysis based on subway segments and high-resolution daily pollution data in China

    CHEN Xiaohong1,2,3, LIU Kun1,3, CAI Sijia4, WANG Yangjie2
Author information +
文章历史 +

摘要

交通领域的环境效益一直是环境经济学关注的焦点, 但囿于数据可得性和模型内生性, 鲜见全国范围内城市轨道交通对周边空气质量影响的研究. 本研究首次将中国已开通地铁的39个城市的地铁段数据与高分辨率日度PM2.5数据集进行匹配, 使用多期双重差分法对新地铁段开通与周边空气污染的因果关系进行了实证分析. 研究发现, 新地铁段开通能够显著改善周边空气质量, 使得周边500米范围内PM2.5浓度下降约2.37µg/m3, 并且这种减污效应在工作日对人均GDP高、 空气污染程度重、 燃煤电厂规模大的城市或某条线路的首段开通地铁段更加明显. 上述影响可能源自地铁开通转移了地面公共交通客流量, 导致地面车流量减少. 进一步发现, 地铁开通存在网络效应, 新地铁段的开通能改善既有地铁段周边的空气质量, 且与新开通地铁段的联系越紧密, 既有地铁段周边空气质量改善程度越高. 健康效益测算结果表明, 地铁开通减少了因PM2.5导致的过早死亡人数, 在样本期间为周边覆盖人口带来每年约114~285亿元的健康经济价值. 本研究结论为精细化揭示地铁建设与空气质量之间因果关系、 促进城市轨道交通科学规划发展提供了理论依据和经验证据, 在城市环境治理与科学发展方面具有启示意义.

Abstract

The environmental benefits of transportation have always been a focus of environmental economics. However, due to data availability and endogeneity issues, there is limited research on the impact of urban rail transit on ambient air quality at a national level. This study innovatively matches data on subway segments in 39 Chinese cities with a high-resolution daily PM2.5 dataset, and employs a multi-period difference-in-differences approach to empirically analyze the causal relationship between the opening of new subway segments and local air pollution. The study finds that the opening of new subway segments significantly improves ambient air quality, leading to a reduction of approximately 2.37µg/m3 in PM2.5 concentration within a 500-meter radius. Moreover, this pollution reduction effect is more pronounced on weekdays in cities with high per capita GDP, heavy air pollution levels, and large-scale coal-fired power plants, or on the initial subway section of a certain line, as well as in the initial segments of certain subway lines. This impact may be attributed to the diversion of public transportation passenger flows from surface transportation, resulting in a decrease in vehicular traffic on the surface. Furthermore, the study identifies network effects of subway openings, as the opening of new segments improves air quality around existing subway segments, and the degree of improvement is higher for existing segments that have closer connections to the newly opened segments. The estimation of health benefits indicates that the opening of subway segments reduces premature deaths caused by PM2.5, bringing about an estimated economic value of approximately 11.4 to 28.5 billion yuan in terms of improved health for the population covered by the subway. The findings of this study provide theoretical and empirical evidence to better understand the causal relationship between subway construction and air quality, and offer insights for the scientific planning and development of urban rail transit, contributing to urban environmental governance and sustainable development.

关键词

轨道交通 / 空气污染 / 网络效应 / 健康效益 / 多期DID方法

Key words

urban rail transit / air pollution / network effects / health benefits / multi-period double difference method

引用本文

导出引用
陈晓红, 刘琨, 蔡思佳, 汪阳洁. 中国地铁对线路周边空气的减污效益评估——基于中国地铁段和高分辨率日度污染数据的分析. 系统工程理论与实践, 2025, 45(4): 1224-1244 https://doi.org/10.12011/SETP2023-2422
CHEN Xiaohong, LIU Kun, CAI Sijia, WANG Yangjie. Assessment of air pollution reduction benefits by Chinese metro systems along their routes—Analysis based on subway segments and high-resolution daily pollution data in China. Systems Engineering - Theory & Practice, 2025, 45(4): 1224-1244 https://doi.org/10.12011/SETP2023-2422
中图分类号: F572   

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基金

国家自然科学基金 (72088101, 72394405, 72173139)
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