Land coverage influences the bacterial community composition in the critical zone of a sub-Arctic basaltic environment

Summers, Stephen; Whiteley, Andrew S.; Kelly, Laura C. and Cockell, Charles S. (2013). Land coverage influences the bacterial community composition in the critical zone of a sub-Arctic basaltic environment. FEMS Microbiology Ecology, 86(3) pp. 381–393.



Silicate weathering improves soils by releasing bioessential nutrients from the bedrock to the soil ecosystem. However, whether bacteria are capable of inhabiting subsurface critical zones (zone of active rock weathering), and their role therein, are unknown. Next-generation sequencing and community fingerprinting permitted us to characterize communities from an Icelandic critical zone environment. Communities were compared with respect to physico-chemical properties of the environment to determine the factors influencing bacterial diversity. We showed that land coverage influenced critical zone communities. Analysis of tree-covered site (TCS) soils exhibited high cell densities (TCS = 2.25 9 107 g -1), whereas lichen- and moss-covered sites (LMS) had lower cell densities (LMS = 1.06 X 107 cells g-1), thought to be a result of the organic carbon produced by the trees. Differences in the bacterial community were observed from the abundance of 16S rRNA gene sequences affiliated with Acidobacteria and Proteobacteria, with TCS possessing higher abundances of Proteobacteria [no of sequences: LMS = 1526 (±497); TCS = 2214 (±531)], specifically Alpha- and Betaproteobacteria, and lower Acidobacteria numbers [no of sequences: LMS = 1244 (±338); TCS = 598 (±140)]. Diversity indices and 16S rRNA gene rarefaction showed that communities from TCS soils had lower α-diversity than sites without, indicative of specialized communities at sites with root-forming plants.

Viewing alternatives


Public Attention

Altmetrics from Altmetric

Number of Citations

Citations from Dimensions

Item Actions



  • Item ORO ID
  • 41345
  • Item Type
  • Journal Item
  • ISSN
  • 1574-6941
  • Project Funding Details
  • Funded Project NameProject IDFunding Body
    Not SetNot SetNERC Centre for Ecology and Hydrology, UK
    Not SetNot SetThe Open University
  • Keywords
  • critical zone; weathering; bacteria; minerals; Soil Microbiology; Molecular Ecology.
  • Academic Unit or School
  • Faculty of Science, Technology, Engineering and Mathematics (STEM)
  • Depositing User
  • Stephen Summers