摘要
高大山脉对大气环流具有阻挡或屏障作用。通过分析测定南岭山地湖泊沉积物中多环芳烃(PAHs)的垂直分布,结合210Pb定年,探讨了大气PAHs污染在南岭山地的沉积历史。结果显示,沉积物中的PAHs主要以低环数化合物为主,其中尤以菲的含量为最高。在剖面深度0～28cm范围内,总多环芳烃的含量范围为86～778ng/g。自1970年开始,PAHs含量持续增加,其中20世纪80、90年代中后期PAHs含量略有降低;在2000年后,沉积柱中的PAHs含量呈急剧增加之势态。多环芳烃在大气迁移过程中发生了组成分异,沉积物中相对富集轻组分(低环数)PAHs,与颗粒物结合的大气干湿沉降是PAHs向偏远山地沉积的主要途径。
High mountains may serve as barrier to atmospheric circulation. In this study, the vertical variations of polycyclic aromatic hydrocarbons （PAHs） were investigated in a sediment core collected from a reservoir in Nanling Mountains. In combining with ^210Pb dating technique, the historical records of atmospheric deposition of PAHs in Nanling Mountains were reconstructed. The results indicated that the deposited PAHs were mainly low molecular weight compounds with phenanthrene being the most dominant. In the core profile （0 -28 cm）, ∑PAHs concentrations ranged from 86- 778 ng/g dry weight. Sedimentary PAHs concentration started to increase since the 1970s, there was a decrease in the late of the 1980s and the late of 1990s, respectively. And sharp increase of PAHs concentrations were observed since 2000. PAHs were undergoing compositional fraction process during atmospheric transportation, and sediments accumulated low molecular weight PAHs. Dry and wet deposition is the most important pathway for PAHs input to remote areas.
出处
《地球化学》
CAS
CSCD
北大核心
2007年第4期357-362,共6页
Geochimica
基金
国家自然科学基金(40202035)
关键词
多环芳烃
大气沉降
沉积记录
南岭山地
polycyclic aromatic hydrocarbons
atmospheric deposition
sediment records
Nanling Mountains
