Oecologia

, Volume 118, Issue 2, pp 225–231

The impact of herbivores on nitrogen mineralization rate: consequences for salt-marsh succession

  • Harm J. van Wijnen
  • René van der Wal
  • Jan P. Bakker
Article

DOI: 10.1007/s004420050722

Cite this article as:
van Wijnen, H., van der Wal, R. & Bakker, J. Oecologia (1999) 118: 225. doi:10.1007/s004420050722

Abstract

Soil net N-mineralization rate was measured along a successional gradient in salt-marsh sites that were grazed by vertebrate herbivores, and in 5-year-old exclosures from which the animals were excluded. Mineralization rate was significantly higher at ungrazed than at grazed sites. In the absence of grazing, mineralization rate increased over the course of succession, whereas it remained relatively low when sites were grazed. The largest differences in mineralization rate between grazed and ungrazed sites were found at late successional stages where grazing pressure was lowest. The amount of plant litter was significantly lower at grazed sites. In addition, the amount of litter and potential litter (non-woody, live shoots) was linearly related to net N-mineralization rate. This implies that herbivores reduced mineralization rate by preventing litter accumulation. Bulk density was higher at grazed salt-marsh sites than at ungrazed sites. This factor may also have contributed to the differences in net N-mineralization rate between grazed and ungrazed sites.

Key words Biogeochemical cyclingGooseHareHerbivoryLitter

Copyright information

© Springer-Verlag Berlin Heidelberg 1999

Authors and Affiliations

  • Harm J. van Wijnen
    • 1
  • René van der Wal
    • 2
  • Jan P. Bakker
    • 1
  1. 1.Laboratory of Plant Ecology, University of Groningen, PO Box 14, NL-9750 AA Haren, The Netherlands e-mail: h.j.van.wijnen@biol.rug.nl, Fax: +31-50-3632273NL
  2. 2.Zoological Laboratory, University of Groningen, PO Box 14, NL-9750 AA Haren, The NetherlandsNL