COVID-19 lockdown: animal life, ecosystem and atmospheric environment.

The outbreak of COVID-19 leads to emergence of the global pandemic, but there is no specific vaccine recommended for COVID-19. More than 216 countries are struggling against the transmission of the disease, recovery and motility. Till date more than 0.948 million deaths out of 30.369 million confirmed cases are reported by WHO. Most of the nations adopted partial or complete 'lockdown' and imposed 'social distancing' to control the rapid transmission of COVID-19 and its consequence. Though global economic growth declined due to nationwide lockdown, there are certain positive impacts on environment. This review article has discussed the effects of nationwide lockdown aiming to community transmission COVID-19 on animal life behaviour and atmospheric environment in different aspects. In the lockdown period, the levels of NO2 and carbon emission remarkably decrease in atmosphere due to restricted consumption of fossil fuel by industries, thermal power stations and air transportations. The concentration of NO2 dropped by 45-54% in the atmosphere of most populated cities in Europe. The intensities of particulate matters PM2.5 and PM10 decreased by 43% and 31% respectively, at lower atmosphere indicating improvement in air qualities in different parts of world caused by less traffic and construction activities. SPM reduced up to 15.9%, showing improvement in surface water quality. New deserted bank has developed due to less river activities in this period. Noise pollution remarkably dropped below 60 db even in crowded cities. Thus, the atmospheric environment has resumed some extent in all respect by means of such global-wide lockdown aiming to control COVID-19 pandemic. The behavioural changes of wild animals, birds, butterfly, pets and street animals that reflected on ecosystem of their relative region indicate the non-interference of human activities on lives of natural creatures during lockdown period. There is certain correlation between atmospheric change with the behavioural changes of natural creature during lockdown period. The objective of this study is to focus the critical analysis of the effect of human activities on atmospheric environment for sustainable ecosystem in long term. Significantly, there is ample scope of research on sustainable development of atmospheric environment and ecosystem of creature in absence of human being.