滇池小流域多环芳烃的沉积学记录及其源解析

Sediment Records and Sources of Polycyclic Aromatic Hydrocarbons in the Small Catchment of Dianchi Lake

研究分析了滇池大石坝小流域沉积柱中16种美国环保署(USEPA)优控多环芳烃(PAHs)的垂直分布情况,并对其来源和生态风险进行了初步评估。结果表明:沉积柱不同深度PAHs总量的变化范围为388.64~1 440.38ng/g,其中主要成分为萘(NAP)和菲(PHE)。从多环芳烃环数来看,沉积物中的PAHs以2~3环为主,其含量为127.86~1 130.12ng/g。根据FLA/(FLA+PYR)、BaA/(BaA+CHR)和IcdP/(IcdP+BghiP)三组比值及PAHs各组分含量分析,燃烧过程是沉积物中PAHs的主要来源。生态风险评估表明,大石坝小流域中PAHs不会造成显著的生态风险。

This study was designed to measure the concentrations of 16 priority polycyclic aromatic hydrocarbons(PAHs)identified by the USEPA in the sediment cores from the Dashiba catchment of Dianchi watershed.Meanwhile,the possible sources and risk assessment of PAHs were also discussed.The total PAH concentrations in the sediment core ranged from 388.64~1 440.38 ng/g,and naphthalene and phenanthrene were the dominant compounds throughout the cores.The PAHs in the sediment core were mainly composed of 2~3 rings.The concentrations of 2~3 rings PAHs in the sediment cores were 127.86~1 130.12 ng/g.The distributions of FLA/(FLA+PYR),BaA/(BaA+CHR)and IcdP/(IcdP+BghiP)show that the main sources of PAHs were from the combustion of fossil fuels,coal and biomass.According to the results of risk assessment,the PAHs may not induce adverse effects on the aquatic ecosystem in the Dashiba catchment.