SciELO - Scientific Electronic Library Online

vol.86 issue3Microhabitat selection by Octomys mimax (Rodentia: Octodontidae) in the Monte Desert is affected by attributes and thermal properties of crevicesSeedling distribution and seed germination of chilean lucumo (Pouteria splendens) in Los Molles, Chile author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Services on Demand




Related links

  • On index processCited by Google
  • Have no similar articlesSimilars in SciELO
  • On index processSimilars in Google


Revista chilena de historia natural

Print version ISSN 0716-078X


NOE, LAURA  and  ABRIL, ADRIANA. Is the nitrification a redundant process in arid regions?: activity, abundance and diversity of nitrifier microorganisms. Rev. chil. hist. nat. [online]. 2013, vol.86, n.3, pp.325-336. ISSN 0716-078X.

We tested if the microbial functional redundancy concept (theory relating changes in ecosystem functioning by species loss) apply for changes in the ammonium-oxidizing community (nitrifier bacteria) due to: a) grazing disturbance, b) seasonal variations (dry season vs. wet season), c) habitat type (soil vs. organic residues), and d) ecological conditions (two eco-regions), in an arid region of central-western of Argentina. We determined: a) abundance of culturable nitrifier bacteria, b) nitrification activity and efficiency, and c) nitrifier community genetic structure by PCR-DGGE (richness and similarity index). Grazing did not change the nitrifier abundance, activity and richness, while seasonally and eco-region effects were scarce. Contrarily, the habitat type affected nitrifier activity, which was higher in organic residues than in soil. All similarity indexes were low (average 0.50, range 0.76-0.18) which suggest high species diversity in these arid eco-regions. Our results indicate that the nitrification process in arid region of Argentina is redundant but it applies only for each habitat. To our knowledge, this is the first functional redundancy study on microbial ecological process in disturbed arid zones, in which we report an important species replacement but without modifications in microorganism abundance and activity.

Keywords : arid Chaco; Monte desert; PCR-DGGE; similarity index; species replacement.

        · abstract in Spanish     · text in English     · English ( pdf )


Creative Commons License All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License