摘要
碳质气溶胶是大气颗粒物的重要组成部分,具有很强的环境和气候效应,是气溶胶科学研究领域的热点.为探究庐山风景区居民区PM_(2.5)中碳质组分的污染特征及来源,于2019年12月2日—2020年10月31日在庐山风景区居民区进行PM_(2.5)样品采集,并对其碳质组分有机碳(OC)和元素碳(EC)进行分析.结果表明,观测期间庐山风景区居民区PM_(2.5)的平均质量浓度为(46.45±18.64)μg·m^(-3),其中OC和EC平均质量浓度分别是(4.08±1.61)μg·m^(-3)和(0.23±0.10)μg·m^(-3),占PM_(2.5)总质量的8.78%和0.50%.且碳质颗粒的污染水平普遍低于城市地区,介于国内其他典型高山背景点之间.采用EC示踪法对PM_(2.5)中的二次有机碳(SOC)进行估算,发现采样期间SOC的平均浓度为(1.51±1.22)μg·m^(-3),占OC的33.2%,表明SOC是PM_(2.5)中OC的重要组分.比较发现春秋两季二次转化率比冬夏两季二次转化率较低.通过碳组分主成分分析表明,除二次污染外,庐山风景区居民区OC和EC的含量受燃煤排放、生物质燃烧排放、机动车排放的影响.后向轨迹分析的结果表明,这些一次源排放的影响主要来自远距离输送.庐山风景区居民区采样期间导致PM_(2.5)中碳质颗粒较高的气流主要来自北方及西南方的工业城市,夏季受夏季风暖湿气流的影响,自然污染源较少,同时夏季降雨较多在一定程度上可以稀释污染物,导致到达庐山风景区居民区的气流轨迹携带的污染物较少.OC和EC的相关性表明,庐山风景区居民区冬季和夏季OC和EC具有同源性,春季和秋季碳质组分来源较为复杂.
As an important component of atmospheric particulate matter(PM),has become a hot spot in the field of aerosol scientific research due to its’severe environmental and climatic effects.In order to study the characteristics and sources of carbonaceous component in PM_(2.5)at the residential areas of Mount Lu Scenic Area,PM_(2.5)were collected from December 2,2019 to October 31,2020.The OC and EC in PM_(2.5)are analyzed using semi-continuous OC/EC analyzer(Sunset Laboratory,USA).The results showed that the average mass concentration of PM_(2.5)was(46.45±18.64)μg·m^(-3),in which the average mass concentration of OC and EC were respectively(4.08±1.61)μg·m^(-3)and(0.23±0.10)μg·m^(-3),accounting for 8.78%and 0.50%of the total mass of PM_(2.5).In addition,the pollution level of carbonaceous component in PM_(2.5)is generally lower than that of urban areas,and between the value of other typical high mountain background spots in China.The EC tracer method was used to estimate the secondary organic carbon(SOC)in PM_(2.5).It was found that the average concentration of SOC was(1.51±1.22)μg·m^(-3),accounting for 33.2%of the OC,indicating that SOC is an important component of OC in PM_(2.5)at the residential areas of Mount Lu Scenic Area.The results showed that SOC conversion rate in spring and autumn was lower than that in winter and summer.The concentration of SOC and O3in the atmosphere are significantly positively correlated(R=0.566),indicating that the oxidation reaction of O3as an atmospheric oxidant has a greater impact on the formation of SOC.The OC/EC ratio was between 8.3 and 27.6,further indicating that the residential areas of Mount Lu Scenic Area are seriously polluted by secondary pollution.The principal component analysis of carbon composition shows that,in addition to secondary pollution,the contents of OC and EC in residential areas of Mount Lu Scenic Area are affected by coal-fired emission,biomass combustion emission and motor vehicle emission.The results of the backward trajectory analysis show t
作者
陈飞凤
郑琪
李杰
李鸿儒
彭林玉
王立夫
冯文钟
幸娇萍
叶清
刘苑秋
陈伏生
肖红伟
CHEN Feifeng;ZHENG Qi;LI Jie;LI Hongru;PENG Linyu;WANG Lifu;FENG Wenzhong;XING Jiaoping;YE Qing;LIU Yuanqiu;CHEN Fusheng;XIAO Hongwei(Key Laboratory of Forest Ecosystem Conservation and Restoration in Poyang Lake Watershed,Jiangxi Agricultural University,Nanchang,330045,China;College of Forestry,Jiangxi Agricultural University,Nanchang 330045,China;Beijing SDL Technology Co.,Ltd,Beijing,102206,China;Jiangxi Mount Lu National Nature Reserve Administration,Jiujiang,332999,China;Key Laboratory of Air Pollution Causes and Control of Jiangxi Province,East China University of Technology,Nanchang,330013,China)
出处
《环境化学》
CAS
CSCD
北大核心
2023年第2期532-543,共12页
Environmental Chemistry
基金
国家自然科学基金(42065007)
江西省教育厅科学技术研究项目(GJJ180226)
江西省大气污染成因与控制重点实验室(东华理工大学)开放基金项目(AE1902)资助。
