Geospatial analysis of vehicular emissions in some parts of Benin City, Nigeria

Abstract

Decline in air quality over the years has been linked to the growing rate of urbanization and the increase in the number of vehicles plying the roads. The focus of this study is to monitor the incidence of vehicular emissions in some parts of Benin City and employ geostatistical techniques such as kriging interpolation to study the spatial distribution of some selected pollutants around the study area. Seven (7) georeferenced points, namely; University of Benin Main Gate, Ekosodin junction, Agen Junction, Super D junction, Nitel junction, Okhunmwun junction and Oluku Market junction were used for data collection. Pollutant from vehicular emission, namely; dinitrogen oxide (NO2), carbon monoxide (CO) including the total radiation were monitored in the morning and evening for a period of 35 days (7th July to 12th August 2020) with the aid of portable toxic gas monitors and radiation alert meters. Other parameters of interest which were also measured include; maximum temperature and wind speed using infra-red thermometers and portable anemometer. To ascertain the quality of the data, selected preliminary analysis, namely; test of normality, test of homogeneity, outlier detection and reliability test were done. Results of the study revealed a growing concentration of CO and NO2 around Ugbowo maingate and Okhunmwun community especially during the peak hours.