摘要
为了探究新乡市PM2.5中δ13C比值的季节性变化特征及其对污染来源的指示作用,于2017年夏冬季节采集PM2.5有效样品91个,并测定了样品中的总碳、水溶性离子和稳定碳同位素比值(δ13C).夏季和冬季的TC浓度平均值分别为11.78μg·m-3和26.6μg·m-3.夏季δ13C比值为-27.70‰^-25.22‰其中前14 d的δ13C比值波动较大平均值为-26.96‰,而后16d的δ13C比值相对稳定,平均值为-25.69‰,而且前半月和后半月火点数具有较大差异同时Knss+浓度与TC质量浓度显著相关(R2=0.62,P<0.01)这说明夏收季节生物质燃烧可能对δ13C比值有显著影响.新乡地区冬季RH与TC/PM25质量比值的显著负相关(R2=0.68,P<0.01),揭示了在霾增长初期以SOA增长为主,而污染期以SIA贡献为主.冬季采样期δ13C比值为-26.72‰^-23.49‰,对霾发展过程中稳定同位素组成的研究发现在霾增长过程中δ13C比值以富集为主,而在霾清除阶段δ13C比值以贫化为主.
We study the seasonal variations of ratios in aerosol fine particulate matter(PM2.5) using 91 PM2.5 samples collected from Xinxiang,China,during the summer and winter in 2017.Mass concentrations of total carbon(TC),water soluble ions,and stable carbon isotope ratios(δ13C) were determined.The mean concentrations of TC in the summer and winter were 11.78 μg·m-3 and26.6 μg·m-3,respectively.The δ13C ratio in the summer ranged from-27.70‰to-25.22‰.The daily δ13C ratio fluctuated in the first half of the summer months(mean-26.96‰),whereas the δ13C ratio in the second half of the summer was relatively stable(mean-25.69‰).The number of fires in the study area during the first half of the summer was quite different to the number during the second half of the summer,meanwhile,there was a positive correlation between the Knss+concentration and the TC mass concentration(R2=0.62,P <0.01).This indicates that biomass burning most likely contributed to variations in During the winter there was a significant negative correlation between winter RH and the TC/PM2.5 mass ratio(R2=0.68,P <0.01),which suggests that SOA growth was dominant in the early stage of haze development,whereas the pollution period was dominated by SIA components.The ratio of δ13C ranged from-26.72‰to-23.49‰,and there was a difference between the variation of the δ13C ratio in haze episode(when it was mainly enriched in the development stage) to that in the stage dominated by depletion.
作者
闫广轩
宋鑫
张靖雯
张朴真
王力鹏
张佳羽
杨争
曹治国
樊静
王跃思
刘子锐
YAN Guang-xuan;SONG Xin;ZHANG Jing-wen;ZHANG Pu-zhen;WANG Li-peng;ZHANG Jia-yu;YANG Zheng;CAO Zhi-guo;FAN Jing;WANG Yue-si;LIU Zi-rui(Henan Key Laboratory of Environmental Pollution Control,Key Laboratory for Yellow River and Huai River Water Enviroment and Pollution Control,Ministry of Education,College of Environment,Henan Normal University,Xinxiang 453007,China;State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry,Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029,China;University of Chinese Academy of Sciences,Beijing 100049,China)
出处
《环境科学》
EI
CAS
CSCD
北大核心
2020年第1期82-89,共8页
Environmental Science
基金
国家重点研发计划项目(2017YFC0210000)
国家自然科学基金项目(41807327)
大气重污染成因与治理攻关项目(DQGG0101)