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2008年6月,在祁连山七一冰川采集雪坑、冰川融水和冰川末端冰样,经过大孔吸附树脂富集后,用GC-MS对样品中的正构烷烃(nC14～nC32)和多环芳烃进行了分析.结果表明,正构烷烃的含量在冰川融水中最高,雪坑次之,冰中最低;多环芳烃的含量在雪坑中最高,冰中最低,冰川融水界于二者之间.正构烷烃与多环芳烃都具有很强的疏水性,在固-液相分配过程中倾向于保留在残留固相中.由于冰川融水样品距冰川末端约1km,沿途地表土壤和植被会贡献部分正构烷烃,所以冰川融水中正构烷烃的含量最高.与正构烷烃不同,多环芳烃较易挥发,而且易被沿途土壤和植被所吸附,导致冰川融水中多环芳烃的含量降低.冰川末端冰中正构烷烃与多环芳烃的含量都很低,可能是由于冰川末端冰年代比较古老,受人类活动的污染较轻.正构烷烃的碳优势指数(CPI值)表明,七一冰川中的正构烷烃主要来自高等植物蜡和化石燃料燃烧产物的混合物,多环芳烃的荧蒽/芘(Fla/Pyr)和菲/蒽(Phe/Ant)比值表明,七一冰川冰雪和冰川融水中检测到的多环芳烃主要来自化石燃料的不完全燃烧.
In June 2008, snow pits, glacial meltwaters and glacier ice samples were collected from the Qiyi Mountain Qiyi Glacier. After macroporous adsorption resin was collected, the contents of n-alkanes (nC14 ~ nC32) and The results showed that the content of n-alkanes was the highest in glacial melt, followed by the snow pit and the lowest in ice. The content of polycyclic aromatic hydrocarbons was the highest in snow pits and the lowest in ice, Between n-alkanes and polycyclic aromatic hydrocarbons are highly hydrophobic, and tend to remain in the residual solid phase in the solid-liquid phase distribution.As the glacial melt water samples from the end of the glacier about 1km, along the surface soil And vegetation contribute some n-paraffins, so glacial meltwater has the highest n-paraffins content.Compared with n-paraffins, PAHs are more volatile and easily adsorbed along soil and vegetation along the route, leading to polycyclic aromatic hydrocarbons Of the glacier ice.The content of n-alkanes and polycyclic aromatics in the ice at the end of the glacier is very low, probably due to the older glacier ice age and less pollution by human activities.The carbon index (CPI) of n-alkanes indicates The main alkanes in the 71 glacier The ratios of Fla / Pyr and Phe / Ant of polycyclic aromatic hydrocarbons (PAHs) from the mixture of higher plant wax and fossil fuel combustion products indicate that the detected polycyclic Aromatics mainly come from incomplete combustion of fossil fuels.