广州市典型臭氧污染时段含氧挥发性有机物来源解析

作者：Li Zhibo; Liu Yang; Zhao Mengke; Zhong Zhuolu; Tian Jiao; Huang Haomin; Fan Liya; Ye Daiqi^*

来源：Acta Scientiae Circumstantiae, 2023, 43(10): 204-214.

DOI：10.13671/j.hjkxxb.2023.0100

• backward trajectories
• oxygenated volatile organic compounds（OVOCs）
• photochemical age-based parameterization method
• potential source contribution function analysis（PSCF）
• source apportionment

Oxygenated volatile organic compounds（OVOCs）are key intermediates in the atmospheric photo-oxidation process and important precursors for ozone production. In this study，we observed the VOCs concentrations during typical ozone pollution hours in Guangzhou using a proton-transfer-reaction time-of-flight mass spectrometry（PTR-TOF-MS）. The results showed that the concentrations of total VOCs were（32.95 ± 16.81）× 10-9，of which OVOCs accounted for 58%~84%；the total OH radical reactivity and the total OFP during daytime hours were 2.40~34.79 s-1 and 131.64×10-9，respectively，both with the largest contribution from OVOCs. Based on the photochemical age parameter method to resolve the sources of each OVOCs，the results showed that methanol was mainly contributed by anthropogenic primary sources （55%~61%），and the percentage of anthropogenic secondary sources was very small（<3%）；formaldehyde and acetaldehyde were mainly from anthropogenic secondary sources and natural sources，and acetone had the highest percentage of background sources（35%~39%），and the percentage of anthropogenic primary sources and natural sources were similar；methyl ethyl ketone（MEK）was mainly from anthropogenic primary sources（46%~52%），followed by anthropogenic secondary sources. After clustering analysis，we obtained three air mass transport paths：trajectory 1 was a northeastern offshore air mass with a long transport path，trajectory 2 and trajectory 3 were from the north-east direction and west direction，respectively，with short transport paths，which were more influenced by anthropogenic activities. Among them，the average concentrations of total OVOCs，methanol，formaldehyde and acetaldehyde were the highest in trajectory 2，and the highest concentration of acetone in trajectory 3，and the average concentration of MEK in each air mass was not much different. The main potential source areas were mainly concentrated in the eastern upwind region such as Dongguan and Huizhou，which required joint regional pollution prevention and control. ? 2023 Science Press.

• 单位
  华南理工大学