泰山顶PM2.5及其二次组分的输送路径与潜在源

Transport Pathway and Potential Sources of PM_(2.5)and Secondary Components at the Top of Mountain Tai

为了明确泰山顶PM_(2.5)及其二次组分的输送路径与潜在来源,基于后向轨迹聚类方法对2015年冬季和春季抵达泰山顶的气团传输轨迹进行聚类分析,并利用PSCF(潜在源贡献因子)和CWT(浓度权重轨迹)方法分析泰山顶冬季和春季PM_(2.5)、SO_4^(2-)、NO_3^-和NH_4^+的潜在源域.结果表明,冬季和春季来自不同方向的气团轨迹对泰山顶PM_(2.5)及其组分的潜在源分布的影响具有明显差异.冬季泰山顶ρ(PM_(2.5))和ρ(NO_3^-)平均值的最高值对应的气团轨迹来自湖北、河南、山东济宁等地区,而来自西北方向的轨迹1和轨迹2分别对应的ρ(SO_4^(2-))和ρ(NH_4^+)平均值最高;春季影响ρ(PM_(2.5))和ρ(NO_3^-)的气团轨迹主要来自西南方向的河南、安徽北部、山东聊城等地区,而源自蒙古国途经内蒙古、山西、河南北部和山东聊城的气团轨迹对ρ(SO_4^(2-))和ρ(NH_4^+)的贡献最大.泰山顶ρ(PM_(2.5))、ρ(SO_4^(2-))、ρ(NO_3^-)和ρ(NH_4^+)的PSCF分布特征与CWT分布特征类似,WPSCF(源区分布概率)和CWT的最高计算值主要集中山东济宁、聊城以及邻近的山西省、河北省和河南省,是泰山顶大气污染物的主要潜在源域.

In order to determine the transport pathways and potential sources of PM2.5as well as the secondary components over the summit of Mount Tai,backward trajectories of daily airflow at the top of the mountain during the winter and spring in 2015 were analyzed by HYSPLIT model using cluster method. Moreover,the potential source contribution function（ PSCF） and concentration weighted trajectory（ CWT） were used to reveal the potential source areas of PM2.5,SO4^2-,NO3^-and NH4^＋. The results showed that there were significant differences in the potential source area distribution of PM2.5,SO4^2-,NO3^-and NH4^＋owing to the airflow trajectories in different directions. In winter,the highest values of PM2.5and NO3^-were from air masses,which were concentrated in Hubei and Henan provinces and Jining in Shandong Province,while the ρ（ SO4^2-） and ρ（ NH4^＋） were highest when airflow was dominated by the northwestern airmasses 1 and 2. However,in spring,the airflow trajectories were mainly from the southwest,which had the biggest contribution to the concentration of PM2.5and NO3^-. In addition,the air mass trajectories from Mongolia,northern Inner Mongolia,Shanxi,Henan and Liaocheng in Shandong contributed most to ρ（ SO4^2-） andρ（ NH4^＋）. The PSCF of ρ（ PM2.5）,ρ（ SO4^2-）,ρ（ NO3^）and ρ（ NH4^＋） on the top of Mount Tai had similar distribution characteristics to that of CWT, and the highest values of WPSCF（ potential contribution algorithm combined with weight factors） and CWT were concentrated in surrounding cities including Liaocheng and Jining cities in Shandong Province andthe adjacent provinces including Shanxi,Hebei and Henan. These were identified as the main potential source sources of the air pollutants on the top of Mount Tai.