华南高山森林大气二次有机气溶胶成因及演化模拟研究

The unclear formation mechanism of biogenic secondary organic aerosols (BSOA) is an important source of uncertainty in the air quality and climate models and is also a key scientific issue to be solved urgently for controlling the current regional complex air pollution in China. Therefore, the proposed project intends to select a typical alpine mountain forest in the photochemically active region in southern China, and uses the high-resolution on-line mass spectrometry technologies for the analysis of volatile and semi-volatile organic compounds to establish a stable and reliable on-site simulation experiment method by using smog chamber. In selected typical air clean and pollution periods, on-site smog chamber simulation and mobile alignment experiments will be conducted to elucidate the formation and photochemical evolution mechanisms of BSOA under relatively clean conditions in the forest around the urban agglomeration, so as to reveal the influence of external pollutants and environmental factors under different pollution conditions. And the contribution of high concentrations of ozone to the formation of BSOA in typical alpine forests were quantified to investigate the effects of the interaction between urban and forest atmosphere on the formation of complex air pollution in the photochemically active areas in southern China. This study will help to reveal the causes and control mechanisms of regional complex air pollution in China, as well as the ecological environmental effects of the forest.

生物源二次有机气溶胶（BSOA）成因机制不清是空气质量与气候变化模式不确定性的重要来源，亦是我国目前区域大气复合污染控制亟待解决的关键科学问题。为此，本申请项目拟选取我国南方光化学活跃区典型高山森林，利用高分辨率的挥发性和半挥发性有机物在线质谱分析技术，建立稳定可靠的现场烟雾箱模拟实验方法；选取典型清洁和污染大气过程，开展现场烟雾箱模拟及移动比对等实验，阐明城市群周边森林清洁大气条件下BSOA的成因及光化学演化机制，进而揭示在不同污染天气过程中外来污染物与环境因素对森林大气中BSOA生成与演化的影响，并量化高浓度臭氧对典型高山森林BSOA生成的贡献大小，探讨城市与森林大气交互作用对华南光化学活跃地区大气复合污染形成的影响和贡献。本研究将有助于揭示我国区域大气复合污染的成因及控制机理，以及森林生态环境效应。

生物源二次有机气溶胶（BSOA）成因机制不清是空气质量与气候变化模式不确定性的重要来源，亦是我国目前区域大气复合污染控制亟待解决的关键科学问题。本项目选取华南光化学活跃区的南岭高山森林，在典型清洁和污染大气过程条件下，开展了BSOA及其前体物的野外观测与烟雾箱现场模拟实验，研究城市群周边森林大气中BSOA的成因及光化学演化机制，研究发现南岭森林大气中臭氧浓度高、氧化性强，典型植物源挥发性有机物异戊二烯的氧化产物（如二羰基化合物）浓度高，在人为污染输入的情况下，会导致气溶胶酸性下降，并加速BSOA的生成。气溶胶中含氮棕碳类物质咪唑，受大气二次生成贡献显著，观测到的浓度是目前全球森林已报道浓度中最高的。本研究有助于揭示我国区域大气复合污染的成因及控制机理，以及森林生态环境效应。..迄今为止，本项目已获得6项重要研究成果，正式发表学术论文11篇（其中SCI论文8篇），完成博士论文1本，硕士论文7本，申请国家发明专利2项。项目负责人入选广东省珠江人才团队项目核心成员。