Urban health, safety and environment (HSE)
M.T. Islam; M. Islam; A.A. Nayeem; A.K. Majumder
Abstract
BACKGROUND AND OBJECTIVES: Air pollution and its associated health impacts have become a major concern worldwide, particularly in developing countries. Anthropogenic activities were significantly reduced during the COVID-19 pandemic, allowing for the opportunity for source reduction of air pollutants. ...
Read More
BACKGROUND AND OBJECTIVES: Air pollution and its associated health impacts have become a major concern worldwide, particularly in developing countries. Anthropogenic activities were significantly reduced during the COVID-19 pandemic, allowing for the opportunity for source reduction of air pollutants. A number of studies have been conducted in Dhaka, but most of them are concentrated on a single ground-monitoring station, making it impossible to draw a comprehensive pollution scenario for the entire city. In contrast, this study evaluated the spatio-temporal changes of urban Particulate Matters (PM) in 70 locations from five different land use categories. Hence, this study investigated the influence of the COVID-19 pandemic on PM1 (aerodynamic diameter ≤1 µm), PM2.5 (aerodynamic diameter ≤2.5 µm) and PM10 (aerodynamic diameter ≤10 µm) concentration during three specific time frames: November 2019 (Pre-lockdown), April 2020 (During lockdown), and November 2020 (Post-lockdown).METHODS: The data were collected through portable air quality meter (AEROQUAL 500) during lockdown (April 2020) and post-lockdown (November 2020) period. Data set of pre-lockdowns (November 2019) was collected from Center for Atmospheric Pollution Studies (CAPS). The Tukey’s Post Hoc Multiple Comparison Test was conducted using Statistical Package for the Social Sciences (SPSSv26) to address the significant changes in air quality between the periods. Additionally, the GIS (Geographical Information System) platform was used to see the spatial and temporal variations of PMs over the city.FINDINGS: The study found that average ground level PM1, PM2.5 and PM10 concentration reduced by 75.1, 75.4, 69.6% and 41.1, 32.6, 29.2% respectively during lockdown compared to pre-lockdown and post-lockdown periods. Moreover, the reduction during lockdown was significant at α=0.05 level. The highest reduction was seen in residential areas from the pre-lockdown to lockdown period, whereas in the lockdown to post-lockdown phase that was found in the industrial areas. Interestingly, the northern part of Dhaka city was less polluted than the southern part in all three studied periods. Besides, the Dhaka city dwellers enjoyed comparatively good quality air in lockdown.CONCLUSION: This study suggested that land use-based source apportionment is required to eliminate the particulate concentration from Dhaka city. Besides, 24 hours continuous data is also important to understand the interaction between particulate concentration and climatic forces. Promoting cleaner transportation options, such as electric vehicles and public transportation is recommended as a means of reducing vehicle emissions. Furthermore, governments could consider implementing emissions regulations, setting limits on emissions, or mandating the use of cleaner fuels and technologies to reduce industrial pollution.
Sustainable urban infrastructure
N. Kumar; R. Tyagi
Abstract
BACKGROUND AND OBJECTIVES:The COVID-19 pandemic has created a global health crisis that had a deep impact on the world and our everyday lives. The deadly virus i.e. SARS-CoV-2 has rapidly spread around the world, posing enormous health, social, economic, and environmental challenges to the entire human ...
Read More
BACKGROUND AND OBJECTIVES:The COVID-19 pandemic has created a global health crisis that had a deep impact on the world and our everyday lives. The deadly virus i.e. SARS-CoV-2 has rapidly spread around the world, posing enormous health, social, economic, and environmental challenges to the entire human population. Countries around the world have implemented complete or partial lockdown measures to mitigate the spread of the coronavirus. Corona lockdown has profound social implications and it has sparked fears of impending economic trouble and recession. Methods: However, this lockdown has also shown some positive effects on the natural environment due to the reduction of pollutant loading from vehicle emission, industries, and other sources. Based on a review of recent research in the relevant area, this paper assesses the effect of COVID-19 pandemic on air and water quality as well as on environmental noise. FINDINGS: A substantial reduction in the level of noxious NO2, particulate matter, and carbon emissions have been observed during the lockdown period, the lockdown also led to an appreciable drop in BOD (biological oxygen demand) and a significant increase in DO (dissolved oxygen) of different river water globally. In addition to this, the anthropogenic noise level has fallen by about one-third due to the COVID-19 lockdown. CONCLUSION: This study reveals that there is a substantial possibility for healing the environment from the detrimental effects of anthropogenic activities through partial or temporary lockdown measures.
Urban transportation systems and traffic management
F. Salehi; A.R. Karbassi; M. Khashaypoor
Abstract
Bus rapid transit is an innovative, high capacity, lower cost public transit solution in metropolitan cities. Idea is to dedicate lanes for quick and efficient transport of passengers to their destinations. In the present investigation the environmental impact assessment of bus rapid transit in ...
Read More
Bus rapid transit is an innovative, high capacity, lower cost public transit solution in metropolitan cities. Idea is to dedicate lanes for quick and efficient transport of passengers to their destinations. In the present investigation the environmental impact assessment of bus rapid transit in Tehran metropolitan city is brought out. For this purpose bus rapid transit Lane No. 10 is investigated. The bus rapid transit Lane No.10 is about 10 km in distance that moves up and down between Azadi and Simon Bolivar Squares. About 77500 passengers using 50 buses are transited per day in lane No. 10. These 50 buses cover a distance of 9600 km/day. The results of present study showed that about 6.5 million liters of fuel is saved annually. It should be pointed out that environmental costs are also reduced for about US$ 1.7 million/yr. The overall score of environmental impact assessment stands at +10 that is indicative of Lane No. 10 compatibility with the environmental considerations.
