Details

Autor(en) / Beteiligte

• Liu, Lei
• Lin, Qiuhan
• Liang, Zhuoran
• Du, Rongguang
• Zhang, Guizhen
• Zhu, Yanhong
• Qi, Bing
• Zhou, Shengzhen
• Li, Weijun

Titel

Variations in concentration and solubility of iron in atmospheric fine particles during the COVID-19 pandemic: An example from China

Ist Teil von

• Gondwana research, 2021-09, Vol.97, p.138-144

Ort / Verlag

Elsevier B.V

Erscheinungsjahr

2021

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• [Display omitted] •Total and soluble Fe in PM2.5 decreased significantly in the COVID-19 lockdown in Hangzhou.•Fe solubility increased due to the enhanced oxidizing capacity in the COVID-19 lockdown.•Vehicular emission is a major source of aerosol Fe in Hangzhou under normal conditions. Iron (Fe) in the atmosphere can affect atmospheric chemical processes and human health. When deposited into oceans, it can further influence phytoplankton growth. These roles of Fe fundamentally depend on its concentration and solubility. However, the sources of aerosol Fe and controlling factors of Fe solubility in megacities remain poorly understood. The outbreak of the COVID-19 pandemic causes large changes in human activities, which provides a unique opportunity to answer these key issues. Field observations were conducted before, during, and after the COVID-19 lockdown in Hangzhou, China. Our results show that in the COVID-19 lockdown stage, the concentrations of total Fe (FeT, 75.0 ng m−3) and soluble Fe (FeS, 5.1 ng m−3) in PM2.5 decreased by 78% and 62%, respectively, compared with those (FeT 344.7 ng m−3, FeS 13.5 ng m−3) in the pre-lockdown stage. The sharp reduction (81%) in on-road vehicles was most responsible for the aerosol Fe decrease. Surprisingly, the Fe solubility increased by a factor of 1.9, from 4.2% in the pre-lockdown stage to 7.8% in the COVID-19 lockdown stage. We found that the atmospheric oxidizing capacity was enhanced after lockdown restrictions were implemented, which promoted the formation of more acidic species and further enhanced the dissolution of aerosol Fe.