Suchergebnisse

The WHO declared the novel Covid-19 virus a global pandemic shortly after it broke out. The deadly virus spread has affected human health and seriously halted many economic and industrial activities globally. However, there has been a blight as there has generally been an improvement in air quality since the deadly Covid-19 pandemic caused various governments to lockdown their cities to regulate the spread of the virus. Since the widespread of Covid-19, there have been several researches to measure the extent of impact Covid-19 city lockdown has had global air quality, but no critical review has been done in Africa as a continent to assess the impact of Covid-19 on the impact of lockdowns on air quality. This study is geared towards a critical review of the impact of lockdowns on air quality in Africa. A total of 117 studies were found after a thorough review, and 87 studies met the screening criteria for the review. The literature was examined from Scopus, Google Scholar, PubMed and Web of Science. The study unraveled that in Africa, most of the studies were carried out on West Africa (45.6%), followed by North Africa (26.6%), East Africa (12.6%), South Africa (10.6%), and Central Africa (4.6%). Most of the studies have assessed the air pollutants like PM2.5, NO2, SO2 and CO. The study shows a significant improvement in air quality in Africa during the Covid-19 city lockdown. The research concludes that economic and industrial activities have resumed as various governments resort to partial city lockdowns. The improved air quality has just become an almost lost battle. Various governments in Africa should lock for other effective means to help continue the fight against air pollution in Africa since Covid-19 lockdowns seem to be short-lived. This varied study on the impact of Covid-19 city lockdowns on air quality will certainly aid policymakers in Africa in finding any gaps, as it defines the perceptions of the existing systematic research. Keywords: Covid-19 pandemic, urban city lockdown, air pollution, air ...

Abstract
A wildfire, an unplanned fire that is mainly uncontrolled and originates in combustible vegetation in rural or urban settings, is one of the most pervasive natural catastrophes in some areas, such as Siberia, California and Australia. Many studies, such as standard reviews, have been undertaken to look into the works of literature on wildfires or forest fires and their effects on aquatic and terrestrial ecosystems. Regrettably, conventional literature reviews failed to identify the important researchers, evolving complexities, emerging research hotspots, trends and opportunities for further research on the ground of wildfire study. The present study employs bibliometric analysis to investigate this study area qualitatively and quantitatively. The Scopus database systems and Web of Science Core Collection yielded 78 qualifying papers, which were then evaluated using Biblioshiny (A bibliometrix tool of R-studio). According to the statistics, the discipline is expanding at a pace that is 13.68% faster than average. So far, three key periods of transformation have been documented: preliminary evolution (8 articles; 1999–2005), gentle evolution (14 articles; 2006–2013) and quick evolution (56 articles; 2014 to 2021). Forest Ecology and Management and Science journals have the highest number of publications, accounting for 7.70% of total wildfire-related articles published from 1999 to 2021. However, recent data indicate that investigators are shifting their focus to wildfires, with the term 'Australia' having the highest frequency (91) and 'wildfire' having the second highest (58) as the most appeared keywords. The present study will provide a foundation for future research on wildfire incidence and management by receiving information by synthesising previously published literature in Australia and around the world.