Abstract
Particulate matter pollution, nowadays, is one of the most concerning environmental problems in Chinese cities, and yet monitoring of PM2.5 (aerodynamic diameter of particle ≤2.5 μm) by means of Environmental Internet of Things (EIoT) is still limited in the urbanizing regions in China. A real-time 1 year continuous observation of PM2.5 by EIoT was carried out at a coastal site in Xiamen City during 2012, with the objective to explore the temporal variations and possible sources of PM2.5 in this urbanizing region. The annual average PM2.5 mass concentration was 32.7 ± 9.6 μg m−3, with the highest level in spring (43.6 ± 5.0 μg m−3) and lowest in summer (21.0 ± 2.5 μg m−3). The mean diurnal pattern of PM2.5 mass concentrations had an obvious morning peak and low values from midnight to dawn. Additionally, the concentrations on workdays were clearly higher in contrast to those on weekends. These results indicate that particulate matter in this region is mainly influenced by anthropogenic activities, and could be effectively scavenged by precipitation. Pollution rise suggested that particulate matters were mainly from civil engineering during the construction of new urban area. A distinct characteristic of particulate matters in this urbanizing region was the low ratio (0.40) of PM2.5/PM10, which might result from the increment of coarse particles emission from freeways, construction, and sea spray. The outcomes also show that EIoT technology is convenient for the management of particulate matter pollution.
Acknowledgments
This research was financially supported by the Knowledge Innovation Program of Chinese Academy of Sciences (No: KZCX2-YW-453, KZCX2-YW-JS404 and KZCX2-EW-408), Commonweal Program of Environment Protection Department of China (No: 201009004).