Substantial high-affinity methanotroph populations in Andisols effect high rates of atmospheric methane oxidation

Hornibrook, Ed R C; Maxfield, Pete J.; Evershed, Richard P.

Abstract

Methanotrophic bacteria in soils derived from volcanic ash (Andisols) were characterized via time series 13C-phospholipid fatty acid (PLFA) labelling. Three Andisols were incubated under 2 ppmv 13CH 4 for up to 18 weeks, thus enabling high-affinity methanotrophs to be selectively characterized and quantified. PLFA profiles from all soils were broadly similar, but the magnitude of the high-affinity methanotrophic populations determined through 13C-PLFA-stable isotope probing displayed sizeable differences. Substantial incorporation of 13C indicated very large high-affinity methanotrophic populations in two of the soils. Such high values are far in excess (10×) of those observed for a range of mineral soils incubated under similar conditions (Bull et al., 2000; Maxfield et al., 2006; 2008a, b). Two of the three Andisols studied also displayed high but variable CH 4 oxidation rates ranging from 0.03 to 1.58 nmolCH 4 g -1 d.wt. h -1. These findings suggest that Andisols, a previously unstudied soil class with respect to high-affinity methanotrophic bacteria, may oxidize significant amounts of atmospheric methane despite their low areal coverage globally. © 2009 Society for Applied Microbiology and Blackwell Publishing Ltd.

• Journal Article Type: Article
• Publication Date: Oct 1, 2009
• Journal: Environmental Microbiology Reports
• Electronic ISSN: 1758-2229
• Publisher: Wiley
• Peer Reviewed: Peer Reviewed
• Volume: 1
• Issue: 5
• Pages: 450-456
• DOI: https://doi.org/10.1111/j.1758-2229.2009.00071.x
• Keywords: Andisols, atmospheric methane oxidation, methanotroph populations
• Public URL: https://uwe-repository.worktribe.com/output/991957
• Publisher URL: http://dx.doi.org/10.1111/j.1758-2229.2009.00071.x