Saxena Abhishek, Raj Shani
Department of Physics, Pacific University Udaipur, 313001, Rajasthan, India.
Department of Botany, Mohanlal Sukhadia University Udaipur, 313001, Rajasthan, India.
Urban Clim. 2021 Jan;35:100754. doi: 10.1016/j.uclim.2020.100754. Epub 2020 Dec 7.
The World Health Organization, which proclaimed the COVID-19 a pandemic in early March 2020, imposed a partial lockdown by the Government of India on 21 March 2020. The aim of this investigation was to measure the change in air pollutants, including particulate matter (PM and PM) and gaseous pollutants (NO, CO and O) during COVID-19 lockdown (25th March to 14th April 2020) across four major polluted cities in North India. In all region, PM, PM, NO and CO were significantly reduced while O has been shown mixed variation with increased in Agra and decreased in all other stations during lockdown. PM was reduced by ~20-50% and highly decreased in Noida. PM was most significantly decreased by 49% in Delhi. NO was reduced by ~10-70%, and high reduction was observed in Noida. Likewise, ~10-60% reduction was found in CO and most significantly decreased in Gurugram. However, an increased in O3 was observed in Agra by 98% while significantly reduced in other sites. Compared to the same timeframe in 2018-2019, PM and PM values for all sites were reduced by more than 40%.
世界卫生组织于2020年3月初宣布新冠疫情为大流行，印度政府于2020年3月21日实施了部分封锁措施。本调查的目的是测量在新冠疫情封锁期间（2020年3月25日至4月14日）印度北部四个主要污染城市空气中污染物的变化情况，包括颗粒物（PM 和 PM）和气态污染物（NO、CO 和 O）。在所有地区，PM、PM、NO 和 CO 均显著减少，而 O 在封锁期间在阿格拉有所增加，在所有其他监测站则有所下降，呈现出混合变化。PM 减少了约20%-50%，在诺伊达降幅很大。PM 在德里降幅最为显著，达49%。NO 减少了约10%-70%，在诺伊达降幅很大。同样，CO 减少了约10%-60%，在古尔冈降幅最为显著。然而，阿格拉的 O3 增加了98%，而在其他地点则显著减少。与2018-2019年的同一时间段相比，所有监测点的 PM 和 PM 值均下降了40%以上。
