乌鲁木齐冬季大气细颗粒物水溶性离子特征及来源  

Characteristics and Sources of Water-Soluble Ions of PM_(2.5) in Winter in Urumqi

作　　者：赵克蕾 刘新春[2] 陆辉[2] 何清[2] 钟玉婷[2] 闫景武 

机构地区：[1]新疆大学资源与环境科学学院,新疆乌鲁木齐830046 [2]中国气象局乌鲁木齐沙漠气象研究所中国气象局树木年轮理化研究重点开放实验室/新疆树木年轮生态重点实验室,新疆乌鲁木齐830002 [3]湖南大学环境科学与工程学院,湖南长沙410082

出　　处：《中国沙漠》2015年第3期707-714,共8页Journal of Desert Research

基　　金：中国沙漠气象科学研究基金项目(Sqj2012011);国家自然科学基金项目(41375162);新疆气象局科学技术研究与应用技术开发项目(MS201408)

摘　　要：为了探讨乌鲁木齐冬季大气细颗粒物的污染水平及其水溶性离子的特征,于2013年1—3月采集大气PM2.5样品,并利用离子色谱仪分析其中的水溶性离子,采用硫转化率、离子相关性分析及后向轨迹模型对其可能来源进行了讨论。结果表明:观测期间采样点PM2.5平均质量浓度为170.13±51.39μg·m-3,水溶性离子总浓度平均值为53.47±23.76μg·m-3,其中3种二次离子(SO2-4、NO-3和NH+4)是水溶性离子的主要组分;不同天气类型下PM2.5和离子浓度差异较大,雾、霾天气二次离子浓度占总浓度的81.99%和86.24%,硫转化率均大于0.1;春节期间由于燃放大量的烟花爆竹,使得PM2.5可溶性离子K+和Cl-浓度急剧上升;NH+4与SO2-4、NO-3相关系数分别为0.975和0.748,(NH4)2SO4、NH4HSO4和NH4NO3是细颗粒物水溶性组分的可能结合方式,Cl-和K+的相关性显著,说明两者具有同源性;固定排放源仍然是乌鲁木齐大气污染物的主要来源,局地大气输送会使大气污染加重。In order to investigate the pollution level of atmospheric fine particles and the characteristics of major water-soluble ions,the fine particles-PM2.5were collected in Urumqi from January to March in 2013,and water-soluble ions were analyzed by ion chromatograph.Based on the sulfur oxidation ratio(SOR),the correlation of ions and the backward trajectory model,the possible emission sources were discussed.The results showed that the average mass concentration of PM2.5and the total water-soluble ions were170.13±51.39μg·m-3 and 53.47±23.76μg·m-3 respectively over the entire sampling period.The secondary ions(SO2-4,NO-3and NH+4)were the major species in water-soluble ions.The mass concentration of PM2.5and water-soluble ions had significant differences in different weather conditions.During fog and hazy days the three secondary ions accounted for 81.99% and 86.24% of the total ions concentration,respectively,and the SOR were higher than 0.1.Moreover,during the Spring Festival,large fireworks brought sharp rises in K+and Cl-concentrations.The correlation coefficient between NH+4and SO2-4,NH+4and NO-3were 0.975 and 0.748 respectively,and they were mainly in the form of(NH4)2SO4,NH4HSO4 and NH4NO3in PM2.5.Good correlation was found between Cl-and K+,which indicated that they may have the same emission sources.Stationary source emissions were still the main pollution in Urumqi,and the pollution could be aggravated by local airflows.

关 键 词：大气细颗粒物 水溶性离子 来源 

分 类 号：X513[环境科学与工程—环境工程]