Greenhouse Gases Concentrations in the Atmosphere Along Selected Roads in Abeokuta,

This study investigated effect of vehicular emission on greenhouse gases concentrations along selected roads of different traffic densities in Abeokuta, Ogun State, Nigeria. Nine roads comprised highway, commercial and residential were selected. Greenhouse Gases (GHGs) were determined from both sides of the roads by using gas samplers placed at 1, 5 and 10m away from the roads at different road segments (up/downhill, bend and flat surface) and replicated three times. The data collected were subjected to descriptive statistics and ANOVA. Means were separated using Duncan’s Multiple Range test. The concentrations of GHGs were CO2>CO> NOx> NO> SOx> CH4 and decreased significantly (P<0.05) as distance increased from the road. Highway with significantly (P<0.05) highest traffic density had the highest concentrations of NO, NOx, CO, CO2, SOx and CH4 with 1.51ppm, 2.22ppm, 22.15ppm, 15.33%, 1.43ppm and 0.85ppm respectively followed by the commercial and residential. Up/downhill had the highest concentrations of GHGs among the road segments followed by flat surface and road bend