title: [Transport and differentiation of polycyclic aromatic hydrocarbons in air from Dashiwei karst Sinkholes in Guangxi, China].
abstract: The typical karst Dashiwei Sinkholes located in Leye County, Guangxi were chosen as the study object. The air samples from the opening of Dashiwei Sinkholes to the underground river profiles were collected by polyurethane foam passive samplers (PUF-PAS), and the meteorological parameters were observed. The 16 PAHs were analyzed using GC-MS. The results showed that the total PAHs concentration in air in Dashiwei Sinkholes ranged from 33.76 ng x d(-1) to 150.86 ng x d(-1), with an average of 80.36 ng x d(-1). The mean concentrations in the cliff, the bottom and the underground river profiles were 67.17, 85.36 and 101.67 ng x d(-1), respectively. The 2-3 rings PAHs (including phenanthrene, anthracene, napnthalene and fluorene) accounted for 87.97% of the total of PAHs. The transport and accumulation processes of PAHs in air in Dashiwei Sinkholes were: the ground to the cliff section to the bottom section and then to the underground river, and the total PAHs concentrations showed an obvious increasing tendency with the decrease in altitude or increase in the length of the underground river. Low molecular weight PAHs compounds (including phenanthrene, anthracene, flourene and fluoranthene) in air went through differentiation at the bottom of the west peak, the bottom of the sinkhole and the underground river. The primary sources of PAHs were pyrogenic sources with atmosphere transport. Ambient temperature was the predominating factor influencing the transport and accumulation of gas phase PAHs in Dashiwei Sinkholes, following by wind speed, wind direction and relative humidity. Relative humidity and the temperature were the predominating factors influencing the differentiation, following by wind speed and wind direction. As a whole, a "cold trapping effect" of POPs was showed obviously in Dashiwei Sinkholes.
authors: School of Environmental Studies, China University of Geoscience, Wuhan 430074, China. karstkxs@126.com
authors: Xiang-Sheng
authors: XS
authors: Kong
authors: Shi-Hua
authors: SH
authors: Qi
authors: Qian
authors: Q
authors: Sun
authors: Bao-Jian
authors: BJ
authors: Huang
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D001272:Atmosphere / Q000032:analysis; D002681:China; D004784:Environmental Monitoring / Q000379:methods*; D008401:Gas Chromatography-Mass Spectrometry; D006813:Humidity; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis*; D013696:Temperature; D014919:Wind
chemical_list: D000393:Air Pollutants; D011084:Polycyclic Aromatic Hydrocarbons