摘要
为探究遵义市秋、冬季PM_(2.5)中水溶性离子的昼夜污染特征及来源,于2020年10月~2021年1月昼(8:00~19:30)和夜(20:00~次日7:30)连续采集遵义市PM_(2.5)样品,对样品中8种水溶性离子含量进行检测,分析其昼夜浓度变化特征,并利用主成分分析-多元线性回归(PCA-MLR)模型解析其来源。结果表明:采样期间遵义市水溶性离子的平均浓度为16.89±9.29μg/m3,呈冬季高、秋季低的季节变化特征。NO-3、NH+4、K+和Cl-的浓度夜晚高于白天,而SO42-、Ca2+和Mg2+的浓度则在白天较高。二次离子(NH+4、NO-3、SO42-)是遵义市主要水溶性离子,秋季浓度占总水溶性离子浓度的81.9%,冬季占比为86.8%。遵义市昼夜水溶性离子的AE/CE值均小于1,说明遵义市PM_(2.5)呈碱性。白天和夜晚颗粒物中NH+4存在形式相同,主要以(NH4)2SO4和NH4NO3形式存在。PCA-MLR源解析表明,二次源、扬尘源、煤炭和生物质燃烧混合源是遵义市PM_(2.5)中水溶性离子的主要来源,贡献率分别为61.86%、19.64%、18.50%。
To explore the diurnal pollution characteristics and sources of water soluble ions in Zunyi, PM_(2.5)samples were continuously collected during daytime(08:00-19:30) and nighttime(20:00-07:30) from October 2020 to January 2021.The samples were detected for contents of 8 water-soluble ions, and diurnal variations characteristics were analyzed. Then principal component analysis-multiple linear regression(PCA-MLR) modeling were performed for water-soluble ions sources apportionment. The results show that the average concentration of water-soluble ions in Zunyi City were 16.89±9.29 μg/m3during the sampling period, the water soluble ions concentrations exhibited obvious seasonal variation, with higher levels in winter than in autumn. The concentrations of NO-3, NH+4, K+, and Cl-in nighttime were higher than that in the daytime, while SO42-, Ca2+and Mg2+were higher in daytime. The secondary ions(NH+4, NO-3, SO42-) were dominant water soluble ions in Zunyi City, accounting for 81.9% of total ions mass concentration in autumn and 86.8% in winter. The ratios of diurnal AE/CE were less than 1, indicating that the PM_(2.5)was alkaline in Zunyi City. NH+4mainly existed in the form of(NH4)2SO4and NH4NO3in particulate matter. The PCA-MLR model indicated that the mainly sources of water soluble ions in PM_(2.5)of Zunyi City were secondary sources(61.86%), dust(19.64%), coal and biomass burning(18.50%).
作者
张勇
陈卓
陈荣祥
保玉心
杨明
ZHANG Yong;CHEN Zhuo;CHEN Rongxiang;BAO Yuxin;YANG Ming(Analytical and Testing Center,Zunyi Medical University,Zunyi Guizhou 563000,China;Research Center for physical and chemical analysis and testing engineering technology,Zunyi Guizhou 563000,China;College of Chemistry and Material Science,Guizhou Normal University,Guiyang 550001,China)
出处
《地球与环境》
CAS
CSCD
北大核心
2023年第1期9-16,共8页
Earth and Environment
基金
国家自然科学基金项目(21767007)
遵义市科技计划项目(遵市科合社字(2017)10号)
遵义医科大学硕士启动资金(F-901)。
