樟树叶片中多环芳烃含量的日变化特征

Diurnal Variation of Concentrations of Polycyclic Aromatic Hydrocarbons (PAHs) in the leaves of Cinnamomum camphora

多环芳烃（PAHs）是由2个或者2个以上苯环组成的一类复杂烃类,它广泛存在于环境中,是由包含C和H的化合物不完全燃烧形成的（Ribes et al.,2003）。城市环境中多环芳烃的最重要来源是化石燃料的燃烧,包括钢铁和石油工业生产中的排放和城市非工业区室外环境供暖燃煤和机动车燃油中的释放（Ribes et al．，2003；王雅琴等，2004）。近几十年来，多环芳烃由于其“三致”效应引起了人们的广泛关注，而植物体能够富集大气中的多环芳烃，所以人们常利用植物体来研究大气中的多环芳烃状况，

Polycyclic aromatic hydrocarbons（PAHs）are a kind of persistent toxic organic pollutants which widely exist in environment. In this study,the diurnal variation of PAHs concentrations in leaves of Cinnamomum camphora was analyzed. The result showed that the concentrations of the total PAHs in the leaves in the daytime were much lower than those at night,and the result was well consistent with the diurnal variation of PAHs in the atmosphere deposition. 3-and 4-rings PAHs compounds were main components of the tested 16 PAHs and the concentrations formed around 80% of the total PAHs. However,the low-rings PAHs and high-rings PAHs accounted for respectively only approximate 10. 40% and 9. 81% of the total PAHs. PHE was a main component of ΣPAHs. The ratio of molecule indicators suggested that the PAHs in the leaves of C. camphora were originated from both petroleum and pyrolytic.