ABSTRACT
BACKGROUND: The production of solid waste continues to increase as the population and standard of living increases. In addition, changes in living conditions can induce significant variation in the quantitative and qualitative characteristics of waste. OBJECTIVES: The aim of the present study was to examine the impact of the lockdown period on the generation of solid waste produced in the city of Marrakech. METHODS: The tonnage of household waste, construction and demolition waste and green waste was collected from the landfill and an analysis was made during the lockdown period in 2020 in comparison with the same period in 2019. RESULTS: The analysis of solid waste tonnage in 2019 and 2020 showed that the lockdown had a significant impact on the various wastes; with a 27.61% decrease for household waste, 6.27% decrease in the case of green waste, and 57.40% decrease for construction and demolition waste. DISCUSSION: The degree to which the tonnage of household waste decreased depended on the standard of living in each district which was defined by housing type. The tonnage of construction and demolition waste was influenced by the halt in construction activity in the city. CONCLUSIONS: The results of the present study showed that the tonnage of household waste and demolition and construction waste decreased during the lockdown period. COMPETING INTERESTS: The authors declare no competing financial interests.
ABSTRACT
The Coronavirus disease (COVID-19) has been transmitted worldwide over a very short time after it originated in China in December 2019. In an attempt to control its spread and reduce its health impacts, several countries including those in the African continent imposed restrictive measures that was termed "lockdown". The outcomes of this lockdown have been reported to be beneficial to air quality worldwide. The main objective of this study is to assess the impact of lockdown due to COVID-19 on nitrogen dioxide (NO2) levels over six major cities in Nigeria. Maps extracted from satellite (Sentinel-5P) were used to indicate the significant reduction in the level of NO2 in the selected cities in Nigeria during two time-intervals, pre-lockdown (December, 2019) and during lockdown (April, 2020). The results show a significant reduction in NO2 levels during the lockdown period compared with its levels during the pre-lockdown period in 2019. The reduction in NO2 concentration levels during lockdown is likely due to less traffic, social distancing and restrictions on business and human activities. There could be an element of uncertainty in the results due to seasonality, as the comparison is done with a different season. However, the magnitude of change due to lockdown is probably much higher than the seasonal variability. Although COVID-19 has negatively impacted the health and economic status of all regions worldwide, it has benefited some aspects of air quality in most countries including Nigeria. This indicates that anthropogenic activities may be managed to reduce air pollution and positively impact the health of human beings.