Archaeol: an indicator of methanogenesis in water-saturated soils

Katie L H Lim, Rich D Pancost, Edward R C Hornibrook, Peter J Maxfield, Richard P Evershed

Research output: Contribution to journalArticle (Academic Journal)peer-review

19 Citations (Scopus)

Abstract

Oxic soils typically are a sink for methane due to the presence of high-affinity methanotrophic Bacteria capable of oxidising methane. However, soils experiencing water saturation are able to host significant methanogenic archaeal communities, potentially affecting the capacity of the soil to act as a methane sink. In order to provide insight into methanogenic populations in such soils, the distribution of archaeol in free and conjugated forms was investigated as an indicator of fossilised and living methanogenic biomass using gas chromatography-mass spectrometry with selected ion monitoring. Of three soils studied, only one organic matter-rich site contained archaeol in quantifiable amounts. Assessment of the subsurface profile revealed a dominance of archaeol bound by glycosidic headgroups over phospholipids implying derivation from fossilised biomass. Moisture content, through control of organic carbon and anoxia, seemed to govern trends in methanogen biomass. Archaeol and crenarchaeol profiles differed, implying the former was not of thaumarcheotal origin. Based on these results, we propose the use of intact archaeol as a useful biomarker for methanogen biomass in soil and to track changes in moisture status and aeration related to climate change.

Original languageEnglish
Article number896727
Number of pages9
JournalArchaea
DOIs
Publication statusPublished - 2012

Keywords

  • SEQUENTIAL REDUCTION PROCESSES
  • ETHER-LINKED GLYCEROLIPIDS
  • INTACT POLAR LIPIDS
  • METHANE PRODUCTION
  • TETRAETHER LIPIDS
  • ORGANIC-MATTER
  • SUBSURFACE SEDIMENTS
  • COMMUNITY STRUCTURE
  • MEMBRANE-LIPIDS
  • COMPONENT PARTS

Cite this