Effect of different wetness conditions on Sphagnum lipid composition in the Erxianyan peatland, central China

• Published in: Organic geochemistry Vol. 44; pp. 1 - 7
• Main Authors: Huang, Xianyu, Xue, Jiantao, Zhang, Jinxiang, Qin, Yangmin, Meyers, Philip A., Wang, Hongmei
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.03.2012; Elsevier
• Subjects: alcohols; alkanes; Animal and plant ecology; Animal, plant and microbial ecology; Biological and medical sciences; carbon; Earth sciences; Earth, ocean, space; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; hydrology; Isotope geochemistry; Isotope geochemistry. Geochronology; isotopes; lipid composition; lipids; Marine and continental quaternary; methanotrophs; microbial activity; mosses and liverworts; peat; peatlands; Sphagnum; Surficial geology; Synecology; Terrestrial ecosystems; vascular plants; China; Far East; Asia; ponds; stable isotopes; Musci; alkanes; lipids; fatty acids; C-13/C-12; Plantae; alcohols; n-alkanes; bryophytes; assimilation; Sphagnum; peat bogs; bogs; peat
• ISSN: 0146-6380; 1873-5290
• DOI: 10.1016/j.orggeochem.2011.12.005

► Lipids in Sphagnum palustre from the Erxianyan peatland were investigated. ► The lipid ACLs are sensitive to hydrological variation. ► Lipids and carbon isotopes indicate microbial activity associated with Sphagnum. Samples of Sphagnumpalustre and peat from the Erxianyan peatland, central China, were analyzed for lipids and their carbon isotopes to investigate how lipid distributions respond to hydrological change and to evaluate the importance of the contribution of microbial lipids to the peat moss. The lipids in samples collected from different hydrological settings in and around a pond and in the central part of the bog show clear variation along the hydrological gradient, with higher n-C23/n-C25 alkane ratio values and lower ACL (average chain length) values of long chain n-alkanes, n-fatty alcohols and n-fatty acids at the wetter sites. Although the relationship between the S. palustre lipids and the hydrological conditions can be partially overprinted in peat by an input from vascular plants, lipid ratios such as Paq and ACL can provide useful qualitative information about Sphagnum contributions. In addition, lipid composition and carbon isotope values provide information about microbial activity associated with S. palustre. The occurrence of a high abundance of 7-methylheptadecane in submerged S. palustre is an indication of cyanobacteria in the living peat moss. The relatively 13C-depleted carbon isotope values of the n-C23 alkane could result from the influence of symbiotic methanotrophs on the carbon available for assimilation by S. palustre.