Spatio-Temporal Analysis of Atmospheric Pollutant Concentrations at Bus Terminals along Major Traffic Corridors in Port Harcourt Urban Areas

This study empirically analyzed atmospheric pollutants concentration especially its relationship to meteorological parameters in the vicinity of bus terminals in the city of Port Harcourt. Data on both atmospheric pollutants ((PM₁, PM_2.5, PM₇, TSP, SO₂, NO₂, CO, VOC and CO) with their meteorological variables were collected with the aid of Aeroqual 300 series multi-Gas Meter and Extech weather station Gavin UID respectively; in Mile 1, Mile 3, Garrison, Rumuola and Lagos park bus terminals which were selected based on their high level of socio-economic activities and high frequency of buses alighting. Data were analysed using the Pearson’s Product Moment Correlation Coefficient, Step-Wise Multiple Regression and Analysis of Variance (ANOVA). Findings indicates that that Relative humidity (RH) had a direct relationship but low correlation with PM₁ PM₇, TSP and CO of correlation values (r) of 0.343, 0.229, 0.271 and 0.146 respectively but inversely correlated with SO₂ (r = -0.476). However, RH had a direct significant relationship with PM_2.5, SO₂, and VOC (r = 0.548, 0.629 and 0.595 respectively at p = 0.05). Temperature had a significant but inverse relationship with PM_2.5, SO₂, and VOC (r = -0.524, -0.641 and -0.6 12 at p = 0.05) and a direct significant relationship with NO₂ (r = 0.712) and CO₂ (r = 0.553.  Wind speed  showed a weak relationship with PM₁ and CO₂  (r = 0.010 and 0.205 ) but inversely and significantly correlated to PM₇, PM₁₀, TSP, CO, PM_2.5, SO₂ and VOC (r = -0.398, -0.398,  -0.436, -432, -0.575, -0.864 and  respectively) which means that as wind speed reduces the concentration of these pollutants increases at the bus terminals. Result showed that there were elevated spatial and temporal concentrations of these pollutants because of calm atmospheric condition prevailing at the bus terminal. Enforcement of stricter laws and regulations to control emissions of these obnoxious air pollutants because of their health implications for commuters is strongly recommended.

Keywords: Air Pollution, Bus terminals, carbon monoxide, emission concentration, vehicular emissions