Description:
Despite the recent progress of studies of polycyclic aromatic hydrocarbons (PAHs) in the Tibetan Plateau (TP), the potential for contaminant transport and accumulation in the Hengduan Mountains are very spare. In the present study, soils and lichen samples were simultaneously collected from 62 sampling sites across the Hengduan Mountains and aimed to investigate the occurrence, distribution pattern and identify their controlling factors of PAHs. The sum of the 16 US EPA’s priority PAHs (∑16PAHs) in the soils and lichen ranged from 59.8 to 1163 ng/g and from 174 to 3362 ng/g, respectively. The measured values of PAHs were higher than those in the northern or northwestern TP reported in corresponding matrices. The compositional fractionation of PAHs along with longitude and latitude of the sampling locations indicates significant influence on the distribution of PAHs by both the Indian Monsoon and the East Asian Monsoon. This distribution pattern is also confirmed by the air back trajectories. PAHs can be transported to the slope of southeast TP by long-range atmospheric transport (LRAT). Both mountain cold-trapping effect and forest filter effect jointly dominated the deposition and distribution of PAHs