Regional trend in ambient air quality footprints in calabar urban, nigeria

Abstract

Poor air quality is widely considered as one of the major environmental hazards confronting several urban centres worldwide. This study examined regional trend in ambient air quality footprints in Calabar Metropolis. Data on emission level of CO, NO2, SO2, H2S, and SPM2.5 were collected using Crowcon Gasman, while point coordinates were collected using Garmin GPSMap 60CSx device. Interpolation algorithm in Geographic Information Systems infrastructure was used to generate the regional trend maps for the metropolis. Parametric analytical techniques such as Analysis of Variance (ANOVA) were employed to test the hypotheses, while descriptive statistics including tables, maps and standard deviation were also used to present the data based on the objectives of the study. The results of the trend surface analysis for the five (5) measured parameters show that CO and SPM2.5 were not significant at P˃0.05 with F-ratio of 0.99 and 2.45 respectively. Thus, the null hypothesis which states that there is no significant change in the regional trend in air quality across Calabar Metropolis was therefore accepted. Analysis for NO2, SO2 and H2S, were significant at P < 0.05 with F-ratio of 3.47, 3.35 and 7.79 respectively, causing the null hypothesis to be rejected. It was therefore recommended that mitigatory measures should be employed for the purpose of ensuring a sustainable, clean and green urban environment.