Wu Cui-Lin, Wang Hong-Wei, Cai Wan-Jin, He Hong-di, Ni An-Ning, Peng Zhong-Ren
Center for Intelligent Transportation Systems and Unmanned Aerial Systems Applications, State Key Laboratory of Ocean Engineering, School of Naval Architecture, Ocean and Civil Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China.
International Center for Adaptation Planning and Design, College of Design, Construction and Planning, University of Florida, PO Box 115706, Gainesville, FL, 32611-5706, USA.
Build Environ. 2021 May;194:107718. doi: 10.1016/j.buildenv.2021.107718. Epub 2021 Feb 18.
The outbreak of COVID-19 has significantly inhibited global economic growth and impacted the environment. Some evidence suggests that lockdown strategies have significantly reduced traffic-related air pollution (TRAP) in regions across the world. However, the impact of COVID-19 on TRAP on roadside is still not clearly understood. In this study, we assessed the influence of the COVID-19 lockdown on the levels of traffic-related air pollutants in Shanghai. The pollution data from two types of monitoring stations-roadside stations and non-roadside stations were compared and evaluated. The results show that NO, PM, PM, and SO had reduced by ~30-40% at each station during the COVID-19 pandemic in contrast to 2018-2019. CO showed a moderate decline of 28.8% at roadside stations and 16.4% at non-roadside stations. In contrast, O concentrations increased by 30.2% at roadside stations and 5.7% at non-roadside stations. This result could be resulted from the declined NOx emissions from vehicles, which lowered O titration. Full lockdown measures resulted in the highest reduction of primary pollutants by 34-48% in roadside stations and 18-50% in non-roadside stations. The increase in O levels was also the most significant during full lockdown by 64% in roadside stations and 33% in non-roadside stations due to the largest decrease in NO precursors, which promote O formation. Additionally, Spearman's rank correlation coefficients between NO and other pollutants significantly decreased, while the values between NO and O increased at roadside stations.
新冠疫情的爆发显著抑制了全球经济增长并对环境产生了影响。一些证据表明，封锁策略已大幅降低了全球各地与交通相关的空气污染（TRAP）。然而，新冠疫情对路边交通相关空气污染的影响仍未得到清晰的认识。在本研究中，我们评估了新冠疫情封锁措施对上海交通相关空气污染物水平的影响。对两类监测站（路边监测站和非路边监测站）的污染数据进行了比较和评估。结果显示，与2018 - 2019年相比，在新冠疫情期间每个监测站的一氧化氮（NO）、细颗粒物（PM）、可吸入颗粒物（PM）和二氧化硫（SO）均下降了约30 - 40%。一氧化碳（CO）在路边监测站适度下降了28.8%，在非路边监测站下降了16.4%。相比之下，路边监测站的臭氧（O）浓度上升了30.2%，非路边监测站上升了5.7%。这一结果可能是由于车辆氮氧化物排放量下降，降低了臭氧滴定。全面封锁措施使路边监测站的一次污染物减少幅度最大，达34 - 48%，非路边监测站为18 - 50%。由于促进臭氧形成的氮氧化物前体减少幅度最大，在全面封锁期间臭氧水平的上升也最为显著，路边监测站上升了64%，非路边监测站上升了33%。此外，路边监测站中一氧化氮与其他污染物之间的斯皮尔曼等级相关系数显著下降，而一氧化氮与臭氧之间的相关系数值上升。
