Characterstics of seasonal variations of leaf n-alkanes and n-alkenes in modern higher plants in Qingjiang, Hubei Province, China

• Published in: Chinese science bulletin 2008-09, Vol.53 (17), p.2659-2664
• Main Authors: Cui, JingWei, Huang, JunHua, Xie, ShuCheng
• Format: Article
• Language: English
• Subjects: Chemistry/Food Science; Earth Sciences; Engineering; Humanities and Social Sciences; Life Sciences; multidisciplinary; n-烯烃; n-烷烃; Physics; Science; Science (multidisciplinary); 平均碳链长度; 环境变化; 高等植物
• ISSN: 1001-6538; 2095-9273; 1861-9541; 2095-9281
• DOI: 10.1007/s11434-008-0194-8

On the basis of GC and GC-MS analyses, the seasonal variation of leaf lipids is observed in five plant species in Qingjiang in Hubei Province. The CPI values （carbon preference index） of n-alkanes decrease gradually from May to November, though the carbon number distributions and the predominant carbon number in an individual species keep unchanged. The declined CPI values might be caused by the leaf fading, which is further supported by a comparison of the defoliated leaves with the fresh leaves. This observation infers the CPI values of n-alkanes in Quaternary sediments can be used as a tool to index the humification, and thus the climatic and the environmental conditions. The plants analyzed here show a remarkable difference in n-alkanes abundance, suggesting their differential contribution to the n-alkanes identified in sediments. The abundance and the compound species of the n-alkenes detected in the plant leaves change greatly with the seasons due to the influence of temperature, with the least compounds being identified in August.