title: Physical disturbance to ecological niches created by soil structure alters community composition of methanotrophs.
abstract: Aggregates of different sizes and stability in soil create a composite of ecological niches differing in terms of physico-chemical and structural characteristics. The aim of this study was to identify, using DNA-SIP and mRNA-based microarray analysis, whether shifts in activity and community composition of methanotrophs occur when ecological niches created by soil structure are physically perturbed. Landfill cover soil was subject to three treatments termed: 'control' (minimal structural disruption), 'sieved' (sieved soil using 2 mm mesh) and 'ground' (grinding using mortar and pestle). 'Sieved' and 'ground' soil treatments exhibited higher methane oxidation potentials compared with the 'control' soil treatment. Analysis of the active community composition revealed an effect of physical disruption on active methanotrophs. Type I methanotrophs were the most active methanotrophs in 'sieved' and 'ground' soil treatments, whereas both Type I and Type II methanotrophs were active in the 'control' soil treatment. The result emphasize that changes to a particular ecological niche may not result in an immediate change to the active bacterial composition and change in composition will depend on the ability of the bacterial communities to respond to the perturbation.
authors.affiliation: School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK Austrian Institute of Technology, Department of Bioresources, A-2444 Seibersdorf, Austria.
authors.forename: Deepak
authors.initials: D
authors.lastname: Kumaresan
authors.forename: Nancy
authors.initials: N
authors.lastname: Stralis-Pavese
authors.forename: Guy C J
authors.initials: GC
authors.lastname: Abell
authors.forename: Levente
authors.initials: L
authors.lastname: Bodrossy
authors.forename: J Colin
authors.initials: JC
authors.lastname: Murrell