HU Yuqing1, SUN Yuchuan1,2, LI Xiaoli1, CAO Min1, YUAN Daoxian1,2
(1.Chongqing Key Laboratory of Karst Environment, School of Geographical Sciences, Southwest University, Chongqing 400715, China;
2. Key Laboratory of Karst Dynamics, Ministry of Natural Resources/Guangxi Zhuang Autonomous Region, Institute of Karst Geology, Chinese Academy of Geological Sciences, Guilin 541004，China)
Abstract:To investigate the concentritions of polycyclic aromatic hydrocarbons (PAHs) in Qingmuguan (QMG) and Laolongdong (LLD) underground rivers, total 84 samples of groundwater were collected all year round. 16 PAHs in different reaches of two underground rivers were measured by gas chromatograph-mass spectrometer (GC-MS), and the spatial distributions were analyzed. Based on the species sensitivity distribution (SSD) model, the ecological risk of the individual and of multiple congeners of PAHs were assessed. The potential affected fractions (PAFs) of PAHs and the potential affected fractions of total PAHs (msPAFRA) were calculated by concentration addition model and response addition model. The results revealed that the concentrations of total PAHs in QMG underground river ranged from 73.8 to 480 ng/L, with a mean value 224 ng/L, while the concentrations of PAHs in LLD ranged from 81.5 to 15200 ng/L, with a mean value 1648 ng/L. The concentrations of PAHs in LLD were obviously higher than that in QMG. The msPAFRA of ∑PAH8 in QMG ranged from 0.1459% to 2.7453%, with a mean value 1.3692%, and the msPAFRA of ∑PAH8 in LLD ranged from 1.0011% to 2.8665%, with a mean value 1.7747%, which was higher than that in QMG. The PAFs in the two underground river catchments showed a trend of Bap＞Ant＞Pyr＞Fla＞Ace＞Nap＞Flu＞Phe, and were less than 5%. The residual level and ecological risks in the two underground river catchments show a trend of import than export, and the distribution characteristics of ecological risk indicates that the aquatic ecological risks in QMG and LLD underground river catchments were mainly affected by Bap, so, direct discharge of industrial and domestic sewage as well as direct consumption of groundwater and living things should be avoided.
Key words:polycyclic aromatic hydrocarbons (PAHs); species sensitivity distribution (SSD); potential affected fractions (PAFs); ecological risk
EARTH AND ENVIRONMENT Vol.49, No.1, Tot No.344, 2021, Page 684-693
