Analysis of PM2.5 sources and potential source areas of typical industrial city in spring and winter: A case study in Liuzhou

In order to reveal the source, potential source distribution and contribution of PM2.5 in spring and winter of Liuzhou City, the characteristics of air pollutant variation in Liuzhou city were analyzed with the 24-hour automatic monitoring data and meteorological data, and the 72-hour daily airflow backward and forward trajectories was clustered by the Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model, meanwhile, the potential source area and concentration contribution were analyzed by the Potential Source Contribution Function(WPSCF) and Concentration Weighted Trajectory (WCWT). The results showed: (1) during the study period, unfavorable dominant wind direction and industrial layout led to serious PM2.5 pollution in spring and winter, besides, industrial and traffic sources were the main local sources; (2) The high value of PM2.5 in spring and winter mainly came from northwest and southeast, among which, the northwest PM2.5 mainly came from the local sources, moreover, the concentration was higher in the west and lower in the east; (3) Backward trajectories showed that the PM2.5 concentration in spring was generally greater than that in winter. In spring and winter, the biggest contributor to PM2.5 pollution in Liuzhou was the shortest transport trajectories, and the trajectories from northwest contributed the least. The atmospheric PM2.5 of Liuzhou transported via airflow had a great influence on the atmospheric environment of Guizhou Province in spring and winter; (4) In spring, the main potential source areas of PM2.5 in Liuzhou were mainly the southeast region of Guangxi, the middle and west regions of Guangdong, the coastal areas of South China Sea, the central region of Hunan, the northwest region of Jiangxi, the east region of Hubei, and the northwest region of Anhui. In winter, they mainly consisted of the southeast region of Guangxi, the southwest region of Guangdong, and the coastal areas of South China Sea. © 2020, Editorial Board of China Environmental Science. All right reserved.