According to WHO approximately 3 million peoples are dying in each year due to air pollution while more than 80% of persons in metropolitan areas are exposed to polluted or contaminated air which is more than from normal or safe limit. In low economic or developing countries, approximately 98% of cities unable to meet with air quality standard of WHO (Figure 1).

Outbreak of coronavirus directly affect the different travel and industry, several areas experienced a sudden fall in the level of air pollution. Centre for Research on Energy and Clean Air reported that, 25% reduction was observed in carbon emission in China by the methods to prevent the spread of COVD -19 disease like as quarantines and travel bans 45. In the first month of lockdown in China, due to reduction in transport, Coal consumption and shut down of industries, China approximately produced 200 million fewer metric tons of CO2 as compare to the same period in 2019. This reduction may save at least 77,000 lives (6. Nitrous oxide (NO2) emissions in the Po Valley region of northern Italy decreased between January 1 and March 11, 2020, coinciding with regional lockdowns. The European Space Agency has collected data from power plants, factories, and automobiles 7. Road transport and power plants are the main source of the NO₂ and causes respiratory diseases like as asthama. It also leads to makes symptoms very worse for those individuals already having heart or lung disease. NO2 emissions have been a major issue in Europe, with many countries exceeding EU restrictions. During late January and early February 2020, the European Space Agency's Sentinel-5P satellite saw a 40% reduction in nitrogen dioxide (NO2) levels across cities and industrial areas in Asia and Europe, compared to the same period in 2019.. Similarly, in UK two weeks after the announcement of nationwide lockdown 60% reduction in NO₂ pollution in some cities was reported with respect to previous year. NASA has reported a 30 percent reduction in NO2 pollution in New York and other North-Eastern US metropolitan areas in the year 2020, compared to the monthly average from 2015 to 2019.

According to the IQAir AirVisual's 2019 World Air Quality Report, India has 21 of the world's most polluted cities, as well as the highest rates of respiratory disease and tuberculosis cases. Such conditions may exacerbate the dangers associated with the coronavirus. However, a sharp drop in pollution and the resulting blue sky indicate a significant shift. PM 2.5, which has a diameter of less than 2.5 micrometres, is particularly hazardous because it can lodge deep within the lungs and spread to other organs and the circulation, posing major health hazards. According to government data, after the lockdown began, the average concentration of PM 2.5 in New Delhi dropped by 71% in a week, from 91 micrograms per cubic metre on March 20 to 26 micrograms per cubic metre on March 27. Anything over 25 is considered dangerous by the World Health Organization.

The Centre for Research on Energy and Clean Air (CREA) compiled data from the Central Pollution Control Board (CPCB), which is part of India's Environment Mi nistry, and found a reduction in nitrogen dioxide levels from 52 per cubic metre to 15 in the same time period. These air pollutant levels have also decreased in cities such as Mumbai, Chennai, Kolkata, and Bangalore. Data shows that dangerous small particulate matter known as PM 2.5 and nitrogen dioxide, which is emitted by auto mobiles and power plants, are already at substantially lower levels in major cities. Even before the countrywide lockdown on March 25, India's creeping shutdowns were having an impact. In the cities of Mumbai, Pune, and Ahmedabad, for example, average nitrogen dioxide levels decreased by 40-50 percent in the first three weeks of March, compared to the same period in 2018 and 2019. This was the least traffic pollution (Air uality and Weather Forecasting And Research (SAFAR) under India's Ministry of Earth Sciences). According to CREA's investigation, India's statewide curfew on March 22 resulted in the lowest one-day traffic pollution levels ever recorded. Other harmful particles, such as PM10, which have a diameter of less than 10 micrometres, have also decreased dramatically, according to the report.In a sense, largest ever global air pollution experiment is being conducted worldwide. Turning off major sources of pollutants such as industrial and transport activities has lead to downfall in pollution level over a short period of time. As a result, in March and April, air quality in the world's major cities improved dramatically. Carbon dioxide (CO2), nitrogen oxides (NO2), and associated ozone emissions from factories and motor traffic (O3) generation, as well as particle matter, all improved air quality (PM). At the height of the outbreak in Wuhan, a million people were under lockdown. China emits more than 30 mega tonnes of nitrogen oxides per year on average, with projections for 2019 surpassing 40 mega tonnes 8.

Despite a temporary drop in global carbon emissions, the International Energy Agency has warned that the economic uncertainties caused by the corona virus pandemic could prevent or delay businesses from investing in renewable energy 91011). Extended quarantine periods, on the other hand, have promoted the adoption of remote work practises 1213. As a result of the unprecedented use of disposable face masks, largequantities of disposable face masks are entering the natural environment, adding to the worldwide burden of plastic waste 8.

Although, this pandemic has caused a drop in activities associated with global production, consumption

and employment as well have inflicted substantial shock at social and economic front. It has significantly reduced air pollution. Emission of various pollutants have been declined majorly due to reduced economic activities during the crisis and will continue to remain low until the activities resume after the crisis is over. A drop of 60% in global air traffic and a temporary dip in CO2 emissions have been observed during the crisis period which arises hope for reduced greenhouse gas emissions and imminent climate change.

However, this would not be a long term improvement as emissions will again reach to higher levels once the economic activity starts and crisis get resolved. Therefore, environmental campaigners demand bailout packages for industrial manufacturers and transportation companies which involve their future operations to result in reduced emissions. This may further be helpful in controlling emission levels and pre crisis levels to go forward.

Due to the pandemic there is a worldwide reductions in aircraft flights. The European Centre for Medium- Range Weather Forecasts (ECMWF) has stated that this reduction may have an impact on weather prediction accuracy, noting commercial aircraft' usage of Aircraft Meteorological Data Relay (AMDAR) as an important contributor to forecast accuracy. Because of the decline in commercial aircraft, the ECMWF estimated that AMDAR coverage will drop by 65 percent or more. 14 According to US National Oceanic and Atmospheric Administration, a similar situation occurred in 2010.

China is responsible for more than half of Asia's nitrogen dioxide emissions. Per tonne of NO2 emitted that has been reduced as a result of the outbreak is the equivalent of removing 62 automobiles from the road each year. As a result, we may estimate that a 10% reduction in NO2 emissions over China is equivalent to removing 48,000 cars from the road. However, in some regions, the 40% reduction in NO2 from 2019 levels in January and February translates to the removal of 192,000 cars.That suggests that if cars were phased out and replaced with electrically driven mass transit in the future, air quality would improve. Increasing the number of electric automobiles and charging stations, as well as electrifying transportation services, will reduce overall tailpipe emissions of air pollutants like NO2. However, the electricity that powers electric vehicles is only as clean as the electricity that powers them. The recent gains in air quality might be maintained by substituting renewable energy and other low-carbon sources for fossil fuel generation. The equivalent of turning off 500 coal power plants for a year would be reducing monthly NO2 emissions from electricity output by 10%. Although this is not the most ideal method for reducing air pollution, it does demonstrate that air pollution is caused by humans. When the pandemic is over, it will be interesting to see whether we invest in a cleaner future, expand existing fossil fuel-intensive businesses, or pursue more sustainable solutions. The pandemic may either demonstrate how a future with less air pollution would look, or it could simply demonstrate the magnitude of the challenge ahead. At the very least, it should prompt governments and businesses to investigate how things could be done differently in the aftermath of the epidemic in order to preserve transient improvements in air quality.

Due to less interference of anthropogenic activity during this global crisis, water quality and water ecosystem has been improved. During the lockdown period, water canals in Venice were cleared and presence of increased number of fishes and waterfowls were marked this could be possible due to the settling of the sediment which is otherwise disturbed by boat traffic. Decrease in pollutant levels have also been observed along the waterways 15.

The statewide lockdown in India, which brought 1.3 billion people to a halt, appears to have had a good impact on the environment, at least temporarily, as seen by clearer skies and cleaner river water than before the crisis. Kanpur and Varanasi have both released images depicting a cleaner Ganga. The absence of major industries has resulted in clean water. In the lack of crowds and in the presence of clean water, fish have resurfaced near Varanasi's ghaat steps, which is unusual to see. In most sections of Delhi, the Yamuna River's water has also began to appear clearer. However, the significant amount of harmful foam that is seen this time of year in southeast Delhi's Kalindi Kunj is still present. The hazardous foam is made up of sewage, detergents, and chemicals from industrial waste. Water quality has improved significantly as a result of the removal of industrial pollutants and garbage. However, water testing is essential to determine the extent of improvement. Unseasonal rains and snowfall in some areas have resulted in higher water flow, which has accompanied the lockdown. Religious activities have diminished, particularly in Varanasi, where there are fewer cremations. Our future approach to minimising Industrial effluents in water bodies should be shaped by the current scenario(https://www.ndtv.com/india-news/cleaner river-water-better-air-quality-positive-effects-of-lockdown-2206553).

However, the crisis' environmental effects were not entirely favourable; in fact, the majority of them were negative. Some of them includes increase in quantity of nonrecyclable waste products, restrictions in import and export services, lack of monitoring and maintenance of natural ecosystems and halt of tourism activity. Delay in recycling activities by municipalities due to covid-19 has emerged into local waste problems. Plastic bags once banned have been resumed by food retailers at checkout points which may cause serious health issues. Furthermore, people's compulsion to stay at home has boosted their consumption of take-out food in single-use packaging. All these changes occurred during coronavirus crisis have created massive waste generation organic as well as non recyclable which challenges the waste management industry. Products with far too large volumes are difficult to be managed in local markets which may further cause its decay and lead to substantial increase in inorganic waste levels. Decaying of products is also responsible to bring sharp increase in levels of methane (CH4) emissions, a greenhouse gas. Decline in export of agricultural and allied products has led to plummet ion of production levels causing increased unemployment in both sectors. Post harvest processing workers particularly womens with low income and supporting their households are facing extreme problems due to this crisis (Table 1). 1516171819

Nationwide lockdown has lead to mis management of land and marine conservation zones, national parks due to confinement of workers in their homes which expose natural ecosystems and protected species toward major risk. Leaving these areas un monitored has brought an increase in illegal activities like poaching, fishing and deforestation. Risk of encroachment and illegal activities in natural ecosystems have further been elevated by stoppage of ecotourism activities. In addition, due to crisis lack of ecotourism, a major income source for many people have raised unemployment which may force many households to harvest natural resources for food and income in an unsustainable manner. Many of the environmental problems produced by the corona virus crisis will gradually go away after the crisis is over and economic activity returns to pre-crisis levels.However, this crisis has given a better understanding to human beings about environmental sustainability, public consumption patterns, and how environmental degradation can be reduced in future.

Coronavirus pandemic have threatened environmental and natural resource bases and it has also caused a severe impact on social and economic status of the society all over the world. All this calls for attention. Most of the population whether rural or urban is dependent on sustainable utilization of available natural resources. They may include small or medium-sized enterprises, involved in various activities such as ecotourism services, biotrade, fisheries and forestry. Covid-19 crisis had a huge negative impact on global trade resulting to a great loss in market. Rural producers, especially womens who are looking their entire households are no more able to carry out their business and livelihood. Prolonged crisis will compel people to disturb sustainable production in order to make their income further leading to over exploitation of natural resources and poverty.