Research article - Peer-reviewed, 2009
Ecophysiological adjustment of two Sphagnum species in response to anthropogenic nitrogen deposition
Wiedermann, Magdalena M.; Gunnarsson, Urban; Ericson, Lars; Nordin, AnnikaAbstract
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)(-); SphagnumPublished in
New Phytologist2009, volume: 181, number: 1, pages: 208-217
Authors' information
Wiedermann, Magdalena M.
Gunnarsson, Urban
Ericson, Lars
Umeå University
Swedish University of Agricultural Sciences, Department of Forest Genetics and Plant Physiology
UKÄ Subject classification
Forest Science
Publication Identifiers
DOI: https://doi.org/10.1111/j.1469-8137.2008.02628.x
URI (permanent link to this page)
https://res.slu.se/id/publ/28562