386 / 2019-02-26 03:15:06

How are the air pollutants distributed? – a case study of Beijing

Air pollution has been a severe problem in Chinese cities, particularly the metropolises where intensive economic activities take place. Many studies analyzed the impact of various types of factors on spatiotemporal distribution of air pollutants. However, few of them examined the relationship between urban morphological characteristics and the distribution of air pollutants. This study aims to investigate such relationships for Beijing, China. We collected data for six types of air pollutants (PM2.5, PM10, SO2, NO2, O3, and CO) and the overall air quality index (AQI), based on hourly data at 35 monitoring stations in Beijing in 2016. The morphological characteristics (Morphological building index) were generated from high resolution remote sensing images. Additional data were obtained for meteorological factors, land use, and population distribution. We employed spatial regression models and spatial stratified heterogeneity models to examine such relationship. The results find that, in the case study city, the constructed morphological building index has a strong correlation with the dispersion of PM2.5 and AQI in the warm season; the road density in the general proximal area impacts air pollutants the most, especially for O3; and population density significantly affects the distribution of PM 2.5, AQI, SO2, and NO2 in the cold season. In addition, distance to the nearest industry sites has significant impacts on the spatial distribution of air pollutants.