Magnani et al. reply (original) (raw)

Nature volume 451, pages E3–E4 (2008) Cite this article

Abstract

Replying to: A. De Schrijver et al. Nature 451, 10.1038/nature06578; W. de Vries et al. Nature 451, 10.1038/nature06579 (2008)

Nitrogen (N) deposition alters ecosystem function in several ways, with important effects on N leaching and water quality, as well as on interspecific competition and biodiversity. These changes have been attributed to ecosystem N saturation, defined as the alleviation of N limitations on rates of biological function1. After an initial fertilization effect, N saturation has also been suggested to reduce plant function and growth2, eventually leading to forest dieback. Although our observation of a substantial positive effect of N deposition on forest carbon (C) sequestration3 does not imply the absence of nitrate losses or other negative effects, as rightly stressed by De Schrijver et al.4, the sustained response observed demonstrates that the fear of a generalized forest decline in response to N fertilization could be overstated, at least within the rather broad N deposition range explored in our analysis. The nature of the observed response of forest C sequestration to N deposition, however, has been questioned outright by de Vries et al.5, who suggested that it could be an artefact resulting from the covariation between N deposition and other environmental variables. The arguments proposed against an overwhelming N effect, however, do not seem to stand up to close scrutiny.

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Authors and Affiliations

  1. Department of Fruit Tree and Woody Plant Science, University of Bologna, Bologna I-40127, Italy
    Federico Magnani
  2. School of GeoSciences, University of Edinburgh, Edinburgh EH93JU, UK
    Maurizio Mencuccini, Paul G. Jarvis, John B. Moncrieff & John Grace
  3. Department of Crop Systems, Forestry and Environmental Sciences, University of Basilicata, Potenza I-85100, Italy
    Marco Borghetti & Vanessa Tedeschi
  4. Departement des Sciences Biologiques, University of Québec à Montréal, Montréal, H3C 3P8, Quebec, Canada
    Frank Berninger
  5. UMR BIOGECO, INRA—Université Bordeaux 1, F-33400, Talence Cedex, France
    Sylvain Delzon
  6. Department of Ecology and Environmental Research, Swedish University of Agricultural Sciences, SE-75007 Uppsala, Sweden
    Achim Grelle
  7. Department of Forest Ecology, University of Helsinki, FIN-00014 Helsinki, Finland
    Pertti Hari & Pasi Kolari
  8. Department of Applied Physics, University of Granada, E-18071 Granada, Spain
    Andrew S. Kowalski
  9. Department of Physical Geography and Ecosystems Analysis, Lund University, S-223 62 Lund, Sweden
    Harry Lankreijer & Anders Lindroth
  10. College of Forestry, Oregon State University, Corvallis, 97331, Oregon, USA
    Beverly E. Law
  11. INRA, UR1263 EPHYSE, F-33883, Villenave d’Ornon, France
    Denis Loustau
  12. Institute for Environment and Sustainability—Climate Change Unit, Joint Research Center, European Commission, Ispra, I-21020, Italy
    Giovanni Manca
  13. Department of Forest Resources and Environment, University of Tuscia, Viterbo I-01100, Italy
    Riccardo Valentini

Authors

  1. Federico Magnani
  2. Maurizio Mencuccini
  3. Marco Borghetti
  4. Frank Berninger
  5. Sylvain Delzon
  6. Achim Grelle
  7. Pertti Hari
  8. Paul G. Jarvis
  9. Pasi Kolari
  10. Andrew S. Kowalski
  11. Harry Lankreijer
  12. Beverly E. Law
  13. Anders Lindroth
  14. Denis Loustau
  15. Giovanni Manca
  16. John B. Moncrieff
  17. Vanessa Tedeschi
  18. Riccardo Valentini
  19. John Grace

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Magnani, F., Mencuccini, M., Borghetti, M. et al. Magnani et al. reply.Nature 451, E3–E4 (2008). https://doi.org/10.1038/nature06580

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