典型西南工业城市春冬季PM2.5来源与潜在源区分析——以柳州市为例

为了揭示柳州城区春冬季PM_2.5的来源及其潜在源区分布和贡献,利用2018年24h自动监测数据和气象数据对柳州市大气污染物浓度变化特征进行了分析,并且使用后向轨迹模型(HYSPLIT)对春冬季柳州市PM_2.5逐日72h气流后向轨迹和前向轨迹进行聚类分析,同时结合潜在源贡献因子分析法(WPSCF)和轨迹浓度权重法(WCWT)对其潜在源区和浓度贡献进行了分析.结果显示,(1)在研究期内,不利的主导风向和工业区布局导致研究区PM_2.5在春冬季污染较严重,且工业源和交通源是其主要本地来源;(2)春冬季PM_2.5高值主要来源于西北和东南方向,其中,西北向PM_2.5主要来源于本地排放,且浓度在空间上呈现西高东低的趋势;(3)春季后向轨迹PM_2.5浓度整体大于冬季,春冬季中对柳州市PM_2.5影响最大轨迹均来自东部的短距离输送,而来自西北的气流轨迹输对PM_2.5贡献最低.春冬季柳州市大气PM_2.5通过气流传...

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 PM_2.5 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 PM_2.5 pollution in spring and winter, besides, industrial and traffic sources were the main local sources; (2) The high value of PM_2.5 in spring and winter mainly came from northwest and southeast, among which, the northwest PM_2.5 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 PM_2.5 concentration in spring was generally greater than that in winter. In spring and winter, the biggest contributor to PM_2.5 pollution in Liuzhou was the shortest transport trajectories, and the trajectories from northwest contributed the least. The atmospheric PM_2.5 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 PM_2.5 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.