南京市区郊区大气PM_(10)、PM_(2.1)中PAHs的分布特征及影响因素  

Characteristics and influence factors of PAHs in PM_(10) and PM_(2.1) in urban and suburban Nanjing, China

作　　者：李皓[1,2] 樊曙先[1,2,3] 张悦[2] 康博识 孙玉 LI Hao;FAN Shu-xian;ZHANG Yue;KANG Bo-shi;SUN Yu(Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Nanjing University of Information Science and Technology, Nanjing 210044,China;Nanjing University of Information Science and Technology, Department of Atmospheric Physics, Nanjing 210044, China;Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing University of Information Science and Technology, Nanjing 210044, China;Meteorology Bureau of Hanjiang District of Yangzhou, Yangzhou 225009, China)

机构地区：[1]南京信息工程大学大气环境与装备技术协同创新中心,江苏南京210044 [2]南京信息工程大学大气物理学院,江苏南京210044 [3]南京信息工程大学中国气象局气溶胶与云降水重点开放实验室,江苏南京210044 [4]扬州市邗江区气象局,江苏扬州225009

出　　处：《中国环境科学》2017年第1期60-68,共9页China Environmental Science

基　　金：国家自然科学基金项目(41275151;41375138;41675132)

摘　　要：2009年11月~2010年7月,同步采集了南京市区郊区大气PM_(10)、PM_(2.1)样品,利用气相色谱-质谱联用仪(GC-MS)对其中16种PAHs进行定量分析.结果表明,南京市区、郊区大气PM_(10)中ΣPAHs浓度范围分别为32.84~245.35ng/m^3、21.43~225.72ng/m^3.PM_(2.1)中分别为19.11~111.57ng/m^3、19.69~125.21ng/m^3,市区和郊区PAHs分布差异不大,均呈现冬季>夏季的季节特征.PM_(10)、PM_(2.1)中PAHs均以4、5、6环为主,占总质量浓度的78.7%~83.1%(PM_(10))、80.5%~87.1%(PM_(2.1)),冬季4环PAHs的比例明显增加.市区和郊区PAHs浓度昼夜变化趋势不同,即市区白天大于夜间,而郊区夜间大于白天.在所测定的气象条件中,温度、相对湿度和PM_(10)浓度对PAHs影响显著,温度、相对湿度对PAHs的贡献为负,而PM_(10)对PAHs贡献为正,暖季(夏秋)PAHs受到气象条件的影响大于冷季(冬春),O_3对5、6环PAHs表现出显著的负贡献.利用后向轨迹分析发现南京受到本地排放和周边地区污染源的影响,来自南京东南和西南方向的短距离输送气团对PAHs浓度上升影响较大.PM2.1and PM10samples were synchronously collected at suburban and urban sites in Nanjing,16kinds ofPAHs were analyzed by the GC-MS.The concentrations of total PAHs at the urban and suburban were in the ranges of32.84~245.35ng/m3and21.43~225.72ng/m3for PM10,respectively,and19.11~111.57ng/m3and19.69~125.21ng/m3forPM2.1.PAHs concentrations at the two sites were close to each other,and show similar seasonal variation with the winterconcentrations larger than those in the summer.PAHs mainly compose of4-,5-and6-ring PAHs that have mass fractions(to total PAH mass)of78.7%~83.1%in PM10and80.5%~87.1%in PM2.1,and the fraction of4-rings PAHs in winter wasclearly larger than those of other seasons.The PAHs at two sites showed different diurnal variations.At the urban site,theconcentration in the daytime was higher than that in the nighttime,whereas values in the nighttime become larger at thesuburban site.Among the various meteorological parameters,the PAH concentration shows clearly negative correlationsto both temperature and relative humidity,and a positive correlation is noticed between the PM10and PAHs.The influenceof meteorological parameters was more significant in warm seasons(summer and autumn)than that in cold seasons(winter and spring).Ozone concentration also had a negative correlation to the5-and6-ring PAHs concentration.Theresults from air mass back-trajectory model show that the accumulation of PAHs was mainly influenced by local emission,and polluted airs from southwest and southeast of Nanjing are also an important source ofthe PAHs through shout-range transport.

关 键 词：PAHS PM10 PM2.1 季节变化 昼夜变化 气象因素 

分 类 号：X511[环境科学与工程—环境工程]