Identification of the spatial patterns of air pollution and its sources in Ogui New Layout, South-East of Nigeria, using remote sensing and GIS technology

Air pollution is one of the main risk factors for human health. It is the deadliest form of environmental pollution, which the World Health Organization has recognized as a significant indicator of the status of the environment. Therefore, there is a need for monitoring of air pollution to reduce health hazards associated with it. In this study, Remote Sensing and Geographic Information System were used to examine the spatiotemporal distribution of air pollutants in Ogui New Layout, South-East, Nigeria so as to advise the populace and relevant agencies on the steps and needs in reducing air pollution. Based on dense industrial clusters, heavy traffic and increasing human population density, strategic places were sampled between two peak hours (8 am and 4 pm). A Haze-dust particulate monitor and a Gasman Air Monitor were used to measure the amounts of PM10, CO, SO2, and NO2. The global positioning system (GPS) coordinates of the sampling spots were recorded using the portable Germin-300 GPS device analyzer which was also used in data processing for creating spatial interpolation maps in ArcMap. ArcGIS 10.5 Erdas Imaging 9.5 software was used to analyze the spatial distribution of contaminants from a source using remote sensing and geographic information system (GIS) methods. Results showed that during the dry season, the air pollutants (PM10, CO, SO2, and NO2) had maximum values of 225, 10.72, 1.74, 1.93 respectively and minimum values of 184, 8.86, 0.82, and 0.45 respectively. During the wet season, PM10, CO, SO2 and NO2 had maximum values of 202, 16.66, 1.65, 0.73 respectively and minimum values of 108, 11.85, 0.69 and 0.26 respectively. Based on the study, it is advised that the local people of Ogui New Layout reduce their exposure to the outdoors especially during the dry season. Key words: Ambient air, air pollutants, spatial-temporal assessment, air quality index.