乌鲁木齐市城区大气PM_(2.5)中水溶性离子组分特征及来源解析  

Characteristics and sources of water-soluble ion components in PM_(2.5)in the urban area of Urumqi City

作　　者：魏疆 赵彩欣 王国华 赵丽莉 WEI Jiang;ZHAO Caixin;WANG Guohua;ZHAO Lili(School of Public Administration,Xinjiang University of Finance and Economics,Urumqi 830012,Xinjiang,China;Xinjiang Urumqi Ecological Environment Monitoring Station,Urumqi 830000,Xinjiang,China)

机构地区：[1]新疆财经大学公共管理学院,新疆乌鲁木齐830012 [2]新疆乌鲁木齐生态环境监测站,新疆乌鲁木齐830000

出　　处：《干旱区地理》2025年第4期623-631,共9页Arid Land Geography

基　　金：新疆财经大学校地合作招标项目(2024SLC005)资助。

摘　　要：为研究乌鲁木齐市大气环境中主要污染物PM_(2.5)的水溶性离子组分及其来源,2023年在城市中部布置采样点,通过膜采样的方式采集样品164个,按照相关测试标准测定PM_(2.5)的质量浓度及各水溶性离子组分浓度,并分析其来源。结果表明:(1)采暖期PM_(2.5)质量浓度及各离子组分浓度均大于非采暖期。(2)采暖期的离子总浓度是非采暖期的15.7倍,采(非)暖期离子总浓度分别占PM_(2.5)浓度的73.84%和26.26%,阴阳离子的比值(AE/CE)分别为0.914和0.600,说明PM_(2.5)化学性质呈碱性。(3)硫氧化率(SOR)和氮氧化率(NOR)的年均值分别为0.43±0.30和0.15±0.13,说明采暖期气态前体物SO_(2)和NO_(2)在外部气象条件影响下二次转化的几率较大;NH_(4)^(+)在采暖期主要以(NH_(4))_(2)SO_(4)和NH_(4)NO_(3)的形式存在,在非采暖期则以NH_(4)NO_(3)的形式存在。(4)主成分分析结果显示,采暖期污染物的主要来源于二次污染、工业生产和机动车尾气污染,其次为矿物粉尘和燃煤污染,累计贡献率达80.24%;非采暖期主要来源为扬尘和工业生产,其次为二次污染,最后为燃煤产生的污染,累计贡献率为86.34%。可以看出,不同时期PM_(2.5)中水溶性离子的来源存在较大的差异。To investigate the water-soluble ion components and their sources in the major air pollutant PM_(2.5)in atmospheric environment of Urumqi City,Xinjiang,China,sampling points were established in the city center in 2023.A total of 164 samples were collected using membrane sampling,and the mass concentration of PM_(2.5)along with the concentration of various water-soluble ion components was measured following relevant testing standards.The sources of these components were also analyzed.The results indicate that:(1)The mass concentration of PM_(2.5)and the concentration of ion components are higher during the heating period than that in the nonheating period.(2)The total ion concentration during the heating period is 15 times of the non-heating period,accounting for 73.84%and 26.26%of the PM_(2.5)concentration,respectively.The anion-to-cation ratio(AE/CE)is 0.914 in the heating period and 0.600 in the non-heating period,indicating that the chemical properties of PM_(2.5)tend to be alkaline.(3)The annual average sulfur oxidation ratio(SOR)and nitrogen oxidation ratio(NOR)are 0.43±0.30 and 0.15±0.13,respectively,suggesting a higher probability of secondary transformation pollution of gaseous precursors SO_(2)and NO_(2)during the heating period due to external meteorological conditions.NH_(4)^(+)primarily exists as(NH_(4))2SO_(4)and NH_(4)NO_(3)during the heating period,whereas in the non-heating period,it mainly exists as NH_(4)NO_(3).(4)Principal component analysis indicates that during the heating period,the main sources of pollutants are secondary pollution,industrial production,and vehicle exhaust,followed by mineral dust and coal combustion,with a cumulative contribution rate of 80.24%.In the non-heating period,the primary sources are dust and industrial production,followed by secondary pollution and coal combustion,with a cumulative contribution rate of 86.34%.These findings demonstrate significant differences in the sources of water-soluble ions in PM_(2.5)between the heating and non-heating periods.

关 键 词：大气污染 离子浓度 机动车尾气 主成分分析 

分 类 号：X513[环境科学与工程—环境工程]