长白山地区大气VOCs的观测研究  

Observation studies on Changbai mountains area atmospheric VOCs

作　　者：王珊[1] 王跃思[2] 张俊刚[2] 毛婷[2] 王明星[2] 

机构地区：[1]兰州大学环境科学系,甘肃兰州730000 [2]中国科学院大气物理研究所,北京100029

出　　处：《中国环境科学》2008年第6期491-495,共5页China Environmental Science

基　　金：国家“973”项目(2007CB407303);国家杰出青年基金项目(40525016);国家“863”项目(2006AA06A301)

摘　　要：为了解我国东北内陆背景大气中挥发性有机物(VOCs)的浓度水平和变化形式,采用3步冷冻浓缩和GC/MS联用技术对长白山地区大气中VOCs进行了为期1年的采样分析.结果表明,长白山地区大气中总挥发性有机物(TVOCs)年平均浓度为(181.7±69.6)×10-9C(碳单位体积比),其中烷、烯、芳香和卤代烃4类物质的百分含量依次为43%、22%、31%和4%.烷烃类物质中异戊烷、2-甲基戊烷、正戊烷和3-甲基戊烷等机动车尾气或汽油挥发特征性物质浓度最高;芳香烃类物质中苯/甲苯的特征比值略高于机动车尾气排放特征比值0.5;烯烃类物质以植物排放的蒎烯、异戊二烯为主.从高浓度VOCs种类分析,长白山地区大气VOCs受汽车污染和森林排放双重控制.TVOCs浓度年度峰值出现在春季,为(206.0±58.9)×10-9C;谷值出现在冬季,为(152.3±53.9)×10-9C.根据等效丙烯浓度的计算,烯烃对该地区O3生成贡献最大,而含量丰富的烷烃、芳香烃则在光化学反应中贡献较小.In order to understand the volatile organic compounds （VOCs） concentration level and its variation type in our background atmosphere in the northeast of China, CCS-GC/MS technology had been used to measure VOCs in Changbai mountains area for one year. In Changbai mountains area the yearly average concentration of TVOCs was （181.7±69.6）×10^-9C（Carbon unit V/V） in which the percentages contants of concentration of alkanes, alkenes, aromatic and halo carbon of VOCs were 43%, 22%, 31%, 4%, respectively. The concentrations of isopentane, 2-methyl-pentane, pentane and 3-methyl-pentane which are from automobile exhaust and gasoline evaporation were highest in alkanes. Benzene/toluene ratio was close to 0.5 which is the characteristic value of automobile exhaust. The concentrations of pinene and isoprene were highest in alkenes. Based on the analysis of species ratio of VOCs, the main sources of VOCs may be relative to both vehicle exhaust and forest emissions in Changbai Mountains. The seasonal variation of VOCs concentration has been displayed with the highest value being （206.0± 58.9）×10^-9C in spring and the lowest being （152.3±53.9）×10^-9C in winter. According to the propylene-equivalent concentration, alkenes contribute most to the production of O3 while alkanes and aromatic which are abundant contribute less in the photochemistry reactivity.

关 键 词：挥发性有机物 季节变化 长白山地区 

分 类 号：X701[环境科学与工程—环境工程] P402[天文地球—大气物理学与大气环境]