Geospatial mapping of ambient air quality & vulnerability of urban areas in Davao City

Abstract

In recent years, industrial production and anthropogenic activities increased the concentration of air pollutants, exacerbating ambient air pollution. Ambient air pollution is considered a significant environmental problem and detrimental to human health. The Philippines is one of the fastest urbanizing countries in East Asia and Davao City is one of the highest and most competitive industrialized cities in the country. Geographic Information System (GIS) is a computer-aided technology used to visualize and map the spatiotemporal variation of air quality levels. In this study, the data of the four parameters, particulate matter 10 (PM10), sulfur dioxide (SO2), nitrogen dioxide (NO2), and ground-level ozone (O3) from the five (5) air quality monitoring stations (DC Stations 2, 7, 11, 14, 15) in Davao City were map using the Inverse Distance Weighting interpolation method. Subsequently, the four maps were overlaid to create an ambient air vulnerability map. Based on the findings, this study conclude that all of the monitoring stations in the city had greatly exceeded the Global Air Quality Guideline Values (GAAQGV) set by the World Health Organization for PM10 and NO2, except for SO2 and O3. Moreover, most stations had increased the concentration of the four pollutants. The vulnerability maps revealed that 23,928 structures are affected within the 1km buffer. There are 13,035 (54.48%) structures considered to be very highly vulnerable, 5,547 (23.18%) are highly vulnerable, 3,078 (12.86%) are moderately vulnerable, and 2,268 (9.48%) are very lowly vulnerable. A big part of the city is classified as highly vulnerable, with only the areas located around Station 3 classified as lowly vulnerable and Station 1 as moderately vulnerable. With this, it indicates that implementing policies that ensure clean and ambient air must be strongly enforced in the community to address the problem of ambient air pollution.