Spatial assessment of land use impact on air quality in mega urban regions, Malaysia

This study aims to determine the impact of land use changes on air quality at the largest conurbation area in Malaysia, Kuala Lumpur Extended Mega Urban Regions (KLEMUR) from 2000 to 2015. Statistical and geostatistical analysis were used to analyse air quality and land use data. The results showed that only the daily average concentration of PM10 at several stations exceeded the concentration suggested by the World Health Organization (WHO). All air pollutants measured showed a rising trend, with the exception of the SO2. The land use trends during the 16-year research period showed an increase in built-up lands (4.0 %) and a reduction in vegetation (3.3 %) and water bodies (2.3 %) which caused the spatial distribution of air pollutants to expand from the centre of KLEMUR to the north and south. Principal Component Analysis (PCA) demonstrated that 52.68 % of the air pollution was influenced by vehicular and industrial emissions given that the strong factor loadings (>0.70) consisted of NO, NO2, NOx, CO and SO2. The land use changes have a significant impact (p < 0.10) on air pollution in KLEMUR since NO, NO2, NOx, CO and SO2 were positively correlated with the built-up lands and negatively correlated with vegetation and water bodies.