摘要
为研究张掖市城区大气细颗粒物(PM_(2.5))的污染特征和来源,于2020年9月至2021年7月在张掖市城区的河西学院和湿地博物馆2个采样点进行了PM_(2.5)样品采集,对PM_(2.5)浓度、化学组成(水溶性无机离子、碳质组分和元素)和来源进行分析.结果表明,河西学院和湿地博物馆两个采样点的年均ρ(PM_(2.5))分别为(73.7±31.8)μg·m^(-3)和(68.1±33.3)μg·m^(-3),季节浓度均值均呈现春季>冬季>秋季>夏季的变化.河西学院采样点的二次水溶性无机离子(SO_(4)^(2-)、NO_(3)-和NH_(4)+)年均值高于湿地博物馆.河西学院采样点的ρ(OC)和ρ(EC)分别为(9.6±5.7)μg·m^(-3)和(2.9±1.6)μg·m^(-3),湿地博物馆采样点的年均ρ(OC)和ρ(EC)分别为(9.2±5.8)μg·m^(-3)和(2.5±1.3)μg·m^(-3),河西学院的含碳组分在各季节均高于湿地博物馆.河西学院和湿地博物馆两个采样点的年均二次有机碳(SOC)在OC中的质量分数分别为49.4%和43.7%,表明张掖市存在较为严重的二次污染.河西学院和湿地博物馆两个采样点的元素浓度年均值分别为(6.0±3.5)μg·m^(-3)和(5.8±3.9)μg·m^(-3),受到人为源的影响,Zn、Ca、Al和Fe等元素浓度水平相对较高.正定矩阵因子分解模型(PMF)结果表明,张掖城区PM_(2.5)的主要贡献源为二次气溶胶(28.0%)、交通源(25.8%)、扬尘源(15.2%)、燃煤源(14.0%)、生物质燃烧和垃圾焚烧源(12.5%)和工艺过程源(4.5%).
To analyze the pollution characteristics and sources of atmospheric fine particulate matter(PM_(2.5))in Zhangye City,PM_(2.5)samples were collected at Hexi University and the Wetland Museum from September 2020 to July 2021.The concentration,chemical components(including water-soluble ions,carbon components,and elements),and sources of PM_(2.5) were analyzed.The results showed that the average annual PM_(2.5) concentrations at Hexi University and the Wetland Museum were(73.7±31.8)μg·m^(-3)and(68.1±33.3)μg·m^(-3),respectively,and the seasonal average concentration was highest in spring,followed by that in winter,autumn,and summer.The average annual concentration of secondary ions(SO_(4)^(2-),NO_(3)-,and NH_(4)+)in Hexi University samples was higher than that in Wetland Museum samples.The concentrations of organic carbon(OC)and elemental carbon(EC)in PM_(2.5) at Hexi University were(9.6±5.7)μg·m^(-3) and(2.9±1.6)μg·m^(-3),respectively,and those at the Wetland Museum were(9.2±5.8)μg·m^(-3) and(2.5±1.3)μg·m^(-3),respectively.The carbon content of Hexi University samples was higher than that of Wetland Museum samples in all seasons.The mass fractions of annual average secondary organic carbon(SOC)in OC at Hexi University and the Wetland Museum were 49.4%and 43.7%,respectively,indicating that there was serious secondary pollution in Zhangye City.The annual concentrations of the measured elements in PM_(2.5) at Hexi University and Wetland Museum were(6.0±3.5)μg·m^(-3) and(5.8±3.9)μg·m^(-3),respectively.The concentrations of Zn,Ca,Al,Fe,and other elements were relatively high due to the influence of human sources.The results from the positive matrix factorization(PMF)model showed that secondary aerosol contributed 28.0%of PM_(2.5) in Zhangye City,followed by traffic sources(25.8%),dust sources(15.2%),coal sources(14.0%),biomass combustion and waste incineration sources(12.5%),and process sources(4.5%).
作者
潘成珂
黄韬
高宏
常莉敏
宋世杰
毛潇萱
王佳欣
赵渊
马建民
PAN Cheng-ke;HUANG Tao;GAO Hong;CHANG Li-min;SONG Shi-jie;MAO Xiao-xuan;WANG Jia-xin;ZHAO Yuan;MA Jian-min(Key Laboratory for Environmental Pollution Prediction and Control,Gansu Province,College of Earth and Environmental Sciences,Lanzhou University,Lanzhou 730000,China;Key Laboratory for Earth Surface Processes,Ministry of Education,College of Urban and Environmental Sciences,Peking University,Beijing 100871,China)
出处
《环境科学》
EI
CAS
CSCD
北大核心
2022年第12期5367-5375,共9页
Environmental Science
基金
国家自然科学基金项目(42177351,41877507)。
