Airborne particulate pollution under restricted human activities: insights from COVID-19 lockdown in Xi'an

LU Yongwei; REN Bo; TIAN Jiaming; LI Biao; WANG Yueshe

doi:10.13205/j.hjgc.202609016

Volume 44 Issue 9

Sep. 2026

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Article Navigation > ENVIRONMENTAL ENGINEERING > 2026 > 44(9): 149-160

LU Yongwei, REN Bo, TIAN Jiaming, LI Biao, WANG Yueshe. Airborne particulate pollution under restricted human activities: insights from COVID-19 lockdown in Xi'an[J]. ENVIRONMENTAL ENGINEERING , 2026, 44(9): 149-160. doi: 10.13205/j.hjgc.202609016

Citation:

LU Yongwei, REN Bo, TIAN Jiaming, LI Biao, WANG Yueshe. Airborne particulate pollution under restricted human activities: insights from COVID-19 lockdown in Xi'an[J]. ENVIRONMENTAL ENGINEERING , 2026, 44(9): 149-160. doi: 10.13205/j.hjgc.202609016

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Airborne particulate pollution under restricted human activities: insights from COVID-19 lockdown in Xi'an

doi: 10.13205/j.hjgc.202609016

State Key Laboratory of Power Engineering Multiphase Flow, Xi'an Jiaotong University, Xi'an 710049, China

Received Date: 2025-06-23
Available Online: 2026-11-05

Abstract

Abstract

This study analyzed the variations in PM_2.5 pollution characteristics in Xi'an before and after the COVID-19 lockdown， based on seasonal observation data from 2019 to 2020. The results showed that during the lockdown period， PM_2.5 concentrations in winter increased significantly， with the proportion of heavy pollution days rising by 23.4%， primarily due to the enhanced contribution of natural sources，such as dust. The chemical composition analysis revealed that the concentrations of anthropogenic secondary inorganic aerosols （e.g.， SO₄^2-， NO₃^-） and organic matter （OM） decreased significantly， while the relative proportion of non-anthropogenic components （e.g.， dust） increased markedly due to the reduction in anthropogenic emissions. Principal component analysis （PCA） indicated that the pollution source structure shifted from coal combustion and biomass burning，to a dual-source pattern dominated by mixed pollution sources and natural dust. Additionally， air mass trajectory simulation demonstrated that enhanced long-range transport in winter further aggravated dust pollution. These findings provide new insights into the evolution mechanisms of air pollution under extreme emission reduction scenarios and offer a scientific basis for optimizing pollution control strategies in the post-pandemic era.
- PM_2.5,
- COVID-19 pandemic,
- pollution characteristics,
- source apportionment,
- regional transport

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References(50)

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