Abstract:

In order to understand the contamination characteristics of PAHs in different environmental media of karst underground river, the authors choose the underground river of Guangxi as a study object. Based on the data of air, groundwater, sediment and soil samples gathered during the same term from 2013 to 2014, contrastive analysis is done in light of the concentration, composition and distribution characteristics of 16 kinds of PAHs. The results show that PAHs with 2 to 3 rings are dominated in the air and underground river water, which accounts for 71.66% and 54.84% of the total PAHs. And PAHs with 4 to 6 rings are dominated in the soil and sediment of the underground river, which accounts for 54.26% and 65.06% of the total PAHs. The distribution of PAHs in environmental media along the underground river indicates that the mean concentration PAHs in upstream area is less than that of midstream, and that of midstream is less than that of downstream, because of pollution discharge and absorption. The percentage of variation of PAHs with 2 to 3 rings indicates that the percentage of the underground river is more than that of sediment which is more than that of soil, but the percentage of variation of PAHs with 4 to 6 rings is opposite.

Key words: polycyclic aromatic hydrocarbons, karst underground river, multimedia, concentration, composition, distribution characteristics