Significant coal combustion contribution to water-soluble brown carbon during winter in Xingtai, China: Optical properties and sources  

作　　者：Dapeng Li Can Wu Si Zhang Yali Lei Shaojun Lv Wei Du Shijie Liu Fan Zhang Xiaodi Liu Lang Liu Jingjing Meng Yuesi Wang Jian Gao Gehui Wang 

机构地区：[1]Key Lab of Geographic Information Science of the Ministry of Education,School of Geographic Sciences,East China Normal University,Shanghai 200241,China [2]School of Public Policy and Administration,Northwestern Polytechnical University,Xi’an 710061,China [3]School of Environment and Planning,Liaocheng University,Liaocheng 252000,China [4]State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry,Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100080,China [5]Chinese Research Academy of Environmental Sciences,Beijing 100012,China [6]Institute of Eco-Chongming,Chenjia Zhen,Chongming,Shanghai 202162,China

出　　处：《Journal of Environmental Sciences》2023年第2期892-900,共9页环境科学学报（英文版）

基　　金：financially supported by the National Natural Science Foundation of China (No. 41773117, 42007202);the National Key R&D Plan, Ministry of Science and Technology of China (Mechanism and chemical process characterization of atmospheric particulate matter multi-isotope fractionation) (No. 2017YFC0212703);the Shanghai Science and Technology Innovation Action Plan (No. 20dz1204011);the program of Institute of Eco-Chongming and ECNU Happiness Flower

摘　　要：To understand the characteristics of atmospheric brown carbon(BrC),daily PM2.5 samples in Xingtai,a small city in North China Plain(NCP),during the four seasons of 2018-2019,were collected and analyzed for optical properties and chemical compositions.The light absorption at 365 nm(abs λ=365 nm)displayed a strong seasonal variation with the highest value in winter(29.0±14.3 M/m),which was 3.2∼5.4-fold of that in other seasons.A strong correlation of abs λ=365 nm with benzo(b)fluoranthene(BbF)was only observed in winter,indicating that coal combustion was the major source for BrC in the season due to the enhanced domestic heating.The mass absorbing efficiency of BrC also exhibited a similar seasonal pattern,and was found to correlate linearly with the aerosol pH,suggesting a positive effect of aerosol acidity on the optical properties and formation of BrC in the city.Positive matrix factorization(PMF)analysis further showed that on a yearly basis the major source for BrC was biomass burning,which accounted for 34% of the total BrC,followed by secondary formation(26.7%),coal combustion(21.3%)and fugitive dust(18%).However,the contribution from coal combustionwas remarkably enhanced in winter,accounting for∼40%of the total.Our work revealed that more efforts of“shifting coal to clean energy”are necessary in rural areas and small cities in NCP in order to further mitigate PM2.5 pollution in China.

关 键 词：Brown carbon Coal combustion HAZE Organic tracers PMF 

分 类 号：X513[环境科学与工程—环境工程]