拉萨市挥发性有机物的组成特征、季节变化和来源解析  

Characteristics and Source Apportionment of Ambient VOCs in Lhasa

作　　者：余家燕 韩燕 陈木兰 张惠芳 陈阳[4] 刘建国[1] YU Jia-yan;HAN Yan;CHEN Mu-lan;ZHANG Hui-fang;CHEN Yang;LIU Jian-guo(Key Laboratory of Environmental Optics and Technology,Anhui Institute of Optics and Fine Mechanics,Chinese Academy of Sciences,Hefei 230031,China;University of Science and Technology of China,Hefei 230026,China;Chongqing Eco-Environmental Monitoring Center,Chongqing 401147,China;Chongqing Institute of Green and Intelligent Technology,Chinese Academy of Sciences,Chongqing 400714,China;Tibet Eco-Environmental Monitoring Center,Lhasa 850031,China)

机构地区：[1]中国科学院安徽光学精密机械研究所环境光学与技术重点实验室,合肥230031 [2]中国科学技术大学,合肥230026 [3]重庆市生态环境监测中心,重庆401147 [4]中国科学院重庆绿色智能技术研究院,重庆400714 [5]西藏自治区生态环境监测中心,拉萨850031

出　　处：《环境科学》2022年第1期113-122,共10页Environmental Science

基　　金：西藏自治区科技计划项目(XZ201801-GA-09)。

摘　　要：目前在世界范围内,由于高原城市海拔高、紫外线照射强烈,造成大气中挥发性有机物的源汇归趋呈现较独特的特点.本研究对2019年拉萨市2个城市站点和1个背景站进行大气挥发性有机物(VOCs)的离线罐采样及实验室组分分析,探究了拉萨地区VOCs体积分数水平、组成特征和来源贡献.拉萨市平均φ(VOCs)为49.83×10^(-9),其中烷烃类最高,占比为61%,其次为含氧VOCs (OVOCs, 12%)、卤代烃(9%)、烯烃(9%)、芳香烃(5%)和炔烃(4%).拉萨市市区站点中,八廓街站和区辐射站的VOCs源贡献顺序为:燃烧源(分别为64%和48%,下同)>交通排放(17%和31%)>工业排放(14%和14%)>溶剂涂料(3%和3%)≈植物+背景(2%和4%).八廓街站燃烧源贡献大,与当地贡香焚烧和供暖排放有关;区辐射站的交通排放贡献较高,与距离交通枢纽近且上风向物流中心有关;工业排放对VOCs具有区域性影响.拉萨地区的VOCs体积分数、组分特征、源类贡献受气象和排放协同影响,呈现明显季节变化和地区差异.本研究可以提供我国典型高原城市的VOCs组成特征,可为高源城市臭氧形成和驱动因素的研究积累基础数据.Due to the high altitude of plateau cities and strong ultraviolet radiation, the sources and fates of volatile organic compounds show unique characteristics. In this study, the atmospheric volatile organic compound(VOCs) samples were collected at two urban sites and one background site using tank sampling in Lhasa in 2019, and then the composition, concentration, and sources were characterized. The results showed that the average φ(VOCs) in Lhasa was 49.83×10^(-9), of which the proportion of alkanes was the highest(61%), followed by OVOCs(12%), halogenated hydrocarbons(9%), olefin(9%), aromatic hydrocarbons(5%), and alkynes(4%). The respective contributions of VOCs sources at urban sites, such as Barkhor Street and Radiation Station in Lhasa, were as follows: combustion(64% and 48%)>traffic emission(17% and 31%)>industrial emission(14% and 14%)>solvents and coatings(3% and 3%)≈plant+background(2% and 4%). The contribution of combustion was large mostly due to local incense burning(especially at Barkhor Street) and heating emissions. Traffic emissions contributed about one third to the VOCs at Radiation Station, which is related to its proximity to the transportation hub and the storage and logistics center upwind. Industrial emissions have a regional impact on ambient VOCs. Under the synergistic influence of meteorology and emissions, VOCs concentration, composition characteristics, and source contribution showed obvious seasonal variations and site differences in the Lhasa area.

关 键 词：挥发性有机污染物(VOCs) 正定矩阵因子分解法(PMF) 拉萨 组成特征 来源解析 

分 类 号：X511[环境科学与工程—环境工程]