Ericson, Lars
- Umeå University
Abstract
Here, it was investigated whether Sphagnum species have adjusted their nitrogen (N) uptake in response to the anthropogenic N deposition that has drastically altered N-limited ecosystems, including peatlands, worldwide.A lawn species, Sphagnum balticum, and a hummock species, Sphagnum fuscum, were collected from three peatlands along a gradient of N deposition (2, 8 and 12 kg N ha(-1) yr(-1)) The mosses were subjected to solutions containing a mixture of four N forms. In each solution one of these N forms was labeled with (15)N (namely (15)NH(4)(+) (15)NO(3)(-) and the amino acids [(15)N] alanine (Ala) and [(15)N] glutamic acid (Glu)).It was found that for both species most of the N taken up was from, followed by Ala, Glu, and very small amounts from. At the highest N deposition site N uptake was reduced, but this did not prevent N accumulation as free amino acids in the Sphagnum tissues.The reduced N uptake may have been genetically selected for under the relatively short period with elevated N exposure from anthropogenic sources, or may have been the result of plasticity in the Sphagnum physiological response. The negligible Sphagnum NO(3)(-) uptake may make any NO(3)(-) deposited readily available to co- occurring vascular plants.
Keywords
amino acids; nitrogen (N) deposition gradient; N uptake; NH(4)(+); NO(3)(-); Sphagnum
Published in
New Phytologist
2009, volume: 181, number: 1, pages: 208-217
SLU Authors
Nordin, Annika
- Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences
- Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences
UKÄ Subject classification
Forest Science
Publication identifier
- DOI: https://doi.org/10.1111/j.1469-8137.2008.02628.x
Permanent link to this page (URI)
https://res.slu.se/id/publ/28562