| 摘要: | The wet deposition flux increased with stronger rainfall intensity. From the congener profiles of PCDD/F and PCB WHO-TEQ(2005) total deposition fluxes, 2,3,4,7,8-PeCDF, 2,3,4,6,7,8-HxCDF, 1,2,3,4,7,8-HxCDF and 1,2,3,7,8-PeCDD dominate the deposition fluxes. PCB-126 and PCB169 are the two most significant congeners that dominate the PCB WHO-TEQ(2005). The simulated results show that the monthly PCDD/F and PCB wet deposition fluxes during 2012 were in the range of 9.26-265 pg WHO-TEQ(2005)/m(2)-month and 0.205-9.38 pg WHO-TEQ/m2-month, respectively. The monthly PCDD/F and PCB wet deposition fluxes during 2013 were 0.152-211 pg WHO-TEQ(2005)/m(2)-month and 0.00823-6.84 pg WHO-TEQ/m(2)-month, respectively. Wet deposition mainly occurs in the high rainfall intensity seasons, such as summer. The simulated results indicate that wet deposition is dominated by the particulate phase. Regarding the annual PCDD/F and PCB total (dry + wet) WHO-TEQ(2005) deposition fluxes, dry deposition fluxes account for 68.0-73.9%. Among these, PCDD/Fs dominate the total deposition (95.9-96.1%) and PCBs contribute only 3.9-4.1%. The average total PCDD/F and PCB-TEQ(2005) deposition (dry + wet) flux in winter (317-429 pg WHO-TEQ/m2-month) was 1.46-2.63 times higher than that in summer (163-216 pg WHO-TEQ/m(2)-month). |
