Get access

Does nitrogen deposition affect soil microfungal diversity and soil N and P dynamics in a high Arctic ecosystem?

Authors

  • Clare H. Robinson,

    1. Department of Life Sciences, King's College, University of London, Franklin-Wilkins Building, 150 Stamford Street, London SE1 9NN, UK
    Search for more papers by this author
  • Philip W. Saunders,

    1. Department of Life Sciences, King's College, University of London, Franklin-Wilkins Building, 150 Stamford Street, London SE1 9NN, UK
    Search for more papers by this author
  • Nanette J. Madan,

    1. Department of Life Sciences, King's College, University of London, Franklin-Wilkins Building, 150 Stamford Street, London SE1 9NN, UK
    Search for more papers by this author
  • E. Janie Pryce-Miller,

    1. Department of Life Sciences, King's College, University of London, Franklin-Wilkins Building, 150 Stamford Street, London SE1 9NN, UK
    Search for more papers by this author
  • Allan Pentecost

    1. Department of Life Sciences, King's College, University of London, Franklin-Wilkins Building, 150 Stamford Street, London SE1 9NN, UK
    Search for more papers by this author

Clare H. Robinson, fax: +44 (0)20 7848 4500, e-mail: clare.robinson@kcl.ac.uk

Abstract

In a high Arctic polar semidesert ecosystem (ambient N deposition c. 0.1 g N m−2 a−1), the effects of N enrichment on the diversity of soil microfungi and on N content and availability in organic and mineral soils were determined. Three N (total: 0, 0.5, 5 g N m−2 a−1) and two P (total 0, 1 g m−2 a−1) treatments were applied, since P may limit response to N in this ecosystem. Organic and mineral soils were sampled in June and August in the second year of treatment for microfungi, pH, moisture content, and total N and P. In the third year, soils were resampled for extractable and total N and P. The fungi isolated were typical of high pH soils in the High Arctic and Antarctic. The species richness and diversity of soil microfungi were very low, with ranges as follows: Shannon diversity, 0.56–1.5; richness, 2–6; evenness, 0.79–0.9. There was no significant effect of treatment on the frequency of occurrence of different taxa of soil microfungi. Time of sampling also had no significant impact on fungal assemblages, although different, more diverse communities were isolated from organic, rather than mineral, soils. Nitrate-N in organic soil decreased significantly when P was added alone, but not when P and N were added together. Addition of 0.5 g N m−2 a−1, a rate deposition already occurring in Greenland and Iceland, appeared to exceed N demand even when P limitation was relieved. There was no apparent soil acidification as a result of the N treatments.

Get access to the full text of this article

Ancillary