广州市旱雨季城市和郊区站点HONO分布特征及其对大气氧化性的贡献  

Spatial distribution of HONO in urban and suburban sites in Guangzhou during dry and rainy seasons and its contribution to atmospheric oxidation

作　　者：田玉洁 程鹏 裴成磊 黄坤伦 陈彦宁 李梅 韩宝彬 运丽君 余毅航 杨闻达 凌基 邓晖 马文彬 TIAN Yujie;CHENG Peng;PEI Chenglei;HUANG Kunlun;CHEN Yanning;LI Mei;HAN Baobin;YUN Lijun;YU Yihang;YANG Wenda;LING Ji;DENG Hui;MA Wenbin(Guangdong-Hongkong-Macao Joint Laboratory of Collaborative Innovation for Environmental Quality,Guangdong Provincial Engineering Research Center for On-line Source Apportionment System of Air Pollution,Institute of Mass Spectrometer and Atmospheric Environment,Jinan University,Institute for Environmental and Climate Research,Jinan University,Guangzhou 510632;Guangzhou Ecological and Environmental Monitoring Center of Guangdong Province,Guangzhou 510308;Guangzhou Hexin Instrument Co.,Ltd,Guangzhou 510530)

机构地区：[1]暨南大学环境与气候学院,暨南大学质谱仪器与大气环境研究所,广东省大气污染在线源解析系统工程技术研究中心,环境质量协同创新粤港澳联合实验室,广州510632 [2]广东省广州生态环境监测中心站,广州510308 [3]广州禾信仪器股份有限公司,广州510530

出　　处：《环境科学学报》2024年第10期121-132,共12页Acta Scientiae Circumstantiae

基　　金：国家重点研发计划项目(No.2023YFC3705502,2023YFC3706103)。

摘　　要：气态亚硝酸(HONO)是对流层羟基自由基(?OH)的初级来源,对于大气氧化性具有重要影响.近年来,广州及周边地区开展了多次HONO观测,但该地区的HONO区域分布和季节变化未见报道.本研究基于2022年广州市区和郊区3个站点的同步观测数据,分析了各站点在典型季节的大气污染状况和HONO分布特征,并计算了HONO对?OH贡献的地区和季节差异.结果表明:广州市HONO浓度较历史观测值较低,可能和广州市大气污染浓度逐年降低的趋势相一致.番禺站((1.49±1.05)μg·m^(-3))HONO浓度最高,南沙站((1.24±1.08)μg·m^(-3))略低于番禺站,而从化站((0.40±0.39)μg·m^(-3))浓度最低.从季节差异来看,番禺站和南沙站的HONO浓度都是旱季高于雨季,和其他污染物基本一致.而从化站HONO浓度在雨季((0.49±0.44)μg·m^(-3))显著高于旱季((0.21±0.10)μg·m^(-3)),可能和局地排放以及化学过程的共同作用有关.3个站点HONO对?OH的贡献排序为番禺站>南沙站>从化站,且雨季显著高于旱季.虽然HONO对?OH的平均贡献仅有O_(3)的13%~48%,但在清晨占主导地位,对于光化学过程的启动起到重要作用.Gaseous nitrous acid(HONO)is a primary source of atmospheric hydroxyl radicals(⋅OH),and it has a significant impact on atmospheric oxidation.Despite multiple HONO observations in Guangzhou and its surrounding areas in recent years,regional distribution and seasonal variations of HONO in this area have not been reported.In this study,based on simultaneous observational data from three sites in urban and suburban areas of Guangzhou in 2022,we analyzed the atmospheric pollution levels,HONO distribution characteristics,and calculated the regional and seasonal differences in HONO’s contribution to⋅OH.The results indicate that HONO concentrations in Guangzhou are relatively lower compared to historical observations,consistent with the trend of decreasing air pollution levels in the city.Among the three sites,Panyu station((1.49±1.05)μg·m^(-3))exhibited the highest HONO concentration,followed by Nansha station((1.24±1.08)μg·m^(-3)),while Conghua station((0.40±0.39)μg·m^(-3))had the lowest concentration.Regarding seasonal differences,HONO concentrations at Panyu and Nansha stations were higher in the dry season than in the rainy season,consistent with other pollutants.Conversely,HONO concentrations at Conghua station((0.49±0.44)μg·m^(-3))were significantly higher in the rainy season compared to the dry season((0.21±0.10)μg·m^(-3)),possibly related to local emissions and chemical processes.The contribution of HONO to⋅OH at the three sites ranked as Panyu station>Nansha station>Conghua station,with a significantly higher contribution in the rainy season than in the dry season.Although the average contribution of HONO to⋅OH is only 13%~48%of that of O_(3),it plays a crucial role in initiating photochemical processes,particularly in the morning.

关 键 词：气态亚硝酸 ·OH自由基 旱雨季分析 污染特征 珠江三角洲 

分 类 号：X511[环境科学与工程—环境工程]