1、第 43 卷第 1 期2023 年 1 月Vol.43,No.1Jan.,2023环境科学学报Acta Scientiae Circumstantiae华南沿海地区夏初PM2.5水溶性离子特征及来源解析刘一鸣1,2,3,郑浩阳4,*,陈阁香5,滕超4,林泽健61.中山大学大气科学学院,广东省气候变化与自然灾害重点实验室,珠海 5190822.南方海洋科学与工程广东省实验室(珠海),珠海 5190823.环珠江口气候环境与空气质量变化野外科学观测研究站,广州 5102754.珠海市气象局,珠海 5190005.广东江扬环保咨询服务有限公司,广州 5106656.生态环境部华南环境科学研究所,广州
2、 510655摘要:2018年6月7日7月10日,利用在线气体和气溶胶成分监测仪(IGAC)在珠海市沿海站对PM2.5中水溶性离子浓度和气体开展连续观测分析.结果发现,夏初沿海地区水溶性离子处于较低水平,SO42-、NH4+、NO3-、Cl-、Na+、Ca2+、K+、Mg2+浓度分别为4.78、1.87、1.16、0.92、0.37、0.27、0.11和0.11 gm-3,其中,代表海洋来源的Na+和Cl-浓度与珠江口东海岸的深圳沿海地区相当.Na+和Cl-呈明显的白天高、夜晚低的日变化 特征,与海盐排放在海陆风环流下的输送有关.基于天气形势分析、气团来源分析和PMF来源解析方法研究了观测期间
3、发生的两次污染过程,一次是受到强热带风暴外围下沉气流影响,一次是受到低压槽系统影响,在两次污染期间珠海沿海站受到偏北气流影响,初夏秸秆燃烧排放的污染物对沿海地区造成重要影响,K+和HONO浓度明显增加,大气氧化性的增加促进了夜间二次颗粒物和白天臭氧的生成,造成大气复合污染.在清洁阶段,珠海沿海地区受偏南气流影响,污染物浓度处于较低水平,海盐影响较大.关键词:PM2.5;水溶性离子;源解析;秸秆燃烧;珠海文章编号:0253-2468(2023)01-0237-10 中图分类号:X51,X16 文献标识码:ACharacteristics and source apportionment of w
4、ater-soluble ions in PM2.5 in early summer in coastal south ChinaLIU Yiming1,2,3,ZHENG Haoyang4,*,CHEN Gexiang5,TENG Chao4,LIN Zejian61.Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies,School of Atmospheric Sciences,Sun Yat-sen University,Zhuhai 5190822.Southern Mari
5、ne Science and Engineering Guangdong Laboratory(Zhuhai),Zhuhai 5190823.Field Scientific Observation and Research Station of Climate Environment and Air Quality Change in the Pearl River Estuary,Guangzhou 5102754.Zhuhai Meteorological Office,Zhuhai 5190005.Guangdong Jiangyang Environmental Protection
6、 Consulting Service Co.,Ltd.,Guangzhou 5106656.South China Institute of Environmental Sciences,MEE,Guangzhou 510655Abstract:From June 7th to July 10th,2018,the online gas and aerosol composition monitor(IGAC)was used to continuously observe and analyze the concentrations of water-soluble ions in PM2
7、.5 and gases at a coastal station of Zhuhai City.The water-soluble ions in the coastal areas in early summer were at a low level,and the concentrations of SO42-,NH4+,NO3-,Cl-,Na+,Ca2+,K+,and Mg2+were 4.78,1.87,1.16,0.92,0.37,0.27,0.11,and 0.11 gm-3,respectively,in which the Na+and Cl-concentrations
8、representing marine sources were comparable to those in the coastal area of Shenzhen on the east coast of the Pearl River Estuary.Concentrations of Na+and Cl-showed obvious diurnal variation characteristics(high during the day and low at night),which were related to the transport of sea spray aeroso
9、l under the sea-land breeze circulation.Based on weather situation analysis,air mass source analysis and PMF source analysis methods,two pollution episodes occurred during the observation period were studied.One was under the control of the downdraft outside the strong tropical storm,and the other w
10、as affected by a low-pressure trough system.During these two episodes,the coastal site was affected by the northerly airflow,and the pollutants emitted from straw burning in early summer had an important impact DOI:10.13671/j.hjkxxb.2022.0448刘一鸣,郑浩阳,陈阁香,等.2023.华南沿海地区夏初PM2.5水溶性离子特征及来源解析 J.环境科学学报,43(1
11、):237-246LIU Yiming,ZHENG Haoyang,CHEN Gexiang,et al.2023.Characteristics and source apportionment of water-soluble ions in PM2.5 in early summer in coastal south China J.Acta Scientiae Circumstantiae,43(1):237-246收稿日期:2022-09-27 修回日期:2022-11-28 录用日期:2022-12-05基金项目:广东省科技计划项目(科技创新平台类)(No.2019B1212010
12、02);国家自然科学基金(No.42105097);中山大学中央高校基本科研业务费专项资金(No.22qntd1908)作者简介:刘一鸣(1993),男,E-mail:;责任作者,E-mail:环境科学学报43 卷on these areas.The concentrations of K+and HONO increased significantly,and the increase in atmospheric oxidation capacity promoted the formation of secondary aerosols at night and ozone during
13、 the day,resulting in atmospheric compound pollution.During the clean days,the coastal areas of Zhuhai were affected by the southerly air flow,the pollutant concentration was at a low level,and the sea salt had a greater impact.Keywords:PM2.5;water-soluble ions;source apportionment;biomass burning;Z
14、huhai1引言(Introduction)PM2.5是指空气动力学粒径小于2.5 m的颗粒物,由于PM2.5可长时间悬浮于空气中,对空气质量、城市 能见度、人体健康和气候变化有重要影响(杨新兴等,2012;吴兑等,2012;陈熙勐等,2019).水溶性离子是PM2.5中的重要组成部分,通常情况下占比可达到60%.水溶性离子主要包括硫酸盐(SO42-)、硝酸盐(NO3-)、铵盐(NH4+)、钠盐(Na+)、氯盐(Cl-)、钙盐(Ca2+)、镁盐(Mg2+)、钾盐(K+)等.其中,SNA(Sulfate、Nitrate、Ammonium),包括SO42-、NO3-和NH4+,是水溶性离子中最重要
15、的组成部分,通常由二次反应生成,它们的前体物分别为二氧化硫(SO2)、二氧化氮(NO2)和氨气(NH3),这些气体可通过大气氧化和气体-颗粒物化学作用转化成颗粒物,是造成霾污染的主要颗粒物组分.在大气中PM2.5及其水溶性离子组分浓度的变化受到气象条件、化学组分、二次反应、排放来源等影响(赵晨曦等,2014;王彤等,2019;周学思等,2019;蒋慧敏等,2021).关于PM2.5水溶性离子特征已有不少研究,主要集中在内陆城市地区,如华北地区的北京(张国峰等,2022)、望都(周甜等,2017)、廊坊(吴烈善等,2015),长三角的上海(黄敏,2022)、南京(陈新星等,2022)、杭州(吴丹
16、等,2017),珠三角的广州(吕文英等,2010)、佛山(杨毅红等,2015),以及川渝的成都(尹寒梅等,2020)、重庆(彭超等,2021)等.针对沿海地区水溶性离子的观测研究相对较少,尤其是华南地区,其水溶性离子特征仍需要进一步深入研究和分析.珠海市位于珠江口西南部,濒临南海,是华南地区典型的沿海城市,空气质量在全国城市排名前列(郑振华,2022),但在特殊气象条件下珠海仍会发生污染事件(周学思等,2019).对其大气污染状况进行研究的结果表明,珠海市的大气污染具有不同于其他大中型城市的污染特征和影响因子(车汶蔚等,2008).当地含有火电厂等工业化石燃烧源、交通移动源、生物质燃烧等污染源(赵新锋等,2017),城市大气受到海洋源和陆地源的双重影响,陆地排放的人为污染物会随气团通过远距离传输到沿海上空,而海洋气溶胶也会传输到陆地,影响颗粒物的化学生成和组分特征.目前,关于珠海大气PM2.5 水溶性离子的变化特征研究较少.为了提升对华南沿海地区PM2.5中水溶性离子的认识,本研究将分析珠海市沿海站PM2.5中水溶性离子 浓度的基本特征和时空变化规律,识别其可能来源,以期为当地政府有效