摘要
利用TEOM1405F型PM_(2.5)测量仪、MARGA水溶性离子在线分析仪和激光雷达对苏州市2016年8月24日—9月6日PM_(2.5)、水溶性离子和气溶胶垂直分布进行了观测,结合气象数据分析了水溶性离子的变化规律及其主要来源。结果表明,观测期间PM_(2.5)平均值为43.4μg/m3,与2014和2015年同期相比下降了42.9%和40.3%。总水溶性无机离子平均值为24.18μg/m^3,约占ρ(PM_(2.5))55.7%,其中ρ(SO_4^(2-))、ρ(NH_4^+)和ρ(NO_3^-)分别占ρ(总离子)的46.0%、25.8%、21.0%。夜间边界层降低,大气垂直扩散条件较差,是造成ρ(PM_(2.5))及ρ(水溶性离子)显著升高的主要原因。ρ(NO_3^-)/ρ(SO_4^(2-))为0.056~1.939,平均值为0.432,表明固定源(燃煤源)仍然是PM_(2.5)的主要来源;PCA方法表明苏州水溶性离子的主要来源于二次污染和燃烧源、海盐和土壤源以及地面扬尘、建筑尘。
The characteristics of PM_（2.5）was analyzed by using MARGA IC Analyzer、TEOM1405F instrument and LIDAR,combining with meteorological conditions from August 24 to September 6,2016 in Suzhou. The average concentrations of PM_（2.5）was43. 4μg/m3,decreased 42. 9% and 40. 3% compared with the same period in 2014 and 2015,which indicated that the control measures were effective. The total water-soluble inorganic ions was 24. 18 μg/m^3,accounting for 55. 7% of PM_（2.5）,and ρ（ SO_4^（2-））,ρ（ NH_4^-） and ρ（NO_3^-） occupied for 46. 0%,25. 8%,21. 0% of PM_（2.5）,respectively. Due to boundary layer was reduced at night,the atmospheric vertical diffusion condition turned worse,the concentration of PM_（2.5）and water-soluble ionsraised significantly. The range of ρ（NO_3^-）/ρ（ SO_4^2-） was 0. 056 ~ 1. 939 and the mean value was 0. 432,which indicated that the fixed source（ firecoal）was still the main source of PM_（2.5）. Source of PM_（2.5）is mainly derived from secondary pollution and combustion,sea salt and soil source and ground dust,construction dust according to PCA method.
出处
《环境监控与预警》
2017年第5期57-61,共5页
Environmental Monitoring and Forewarning
基金
苏州市科技计划基金资助项目(SS201524)
