How Phosphorus Availability Affects the Impact of Nitrogen Deposition on Sphagnum and Vascular Plants in Bogs

Research output: Contribution to journalArticleAcademicpeer-review

100 Citations (Scopus)

Abstract

To elucidate the impact of high nitrogen (N) deposition on intact bog vegetation, as affected by phosphorus (P) availability, we conducted a 4-year fertilization experiment with N and P at six sites, one with moderate N deposition and five with high N deposition. During the growing season, N (40 kg ha–1 ya–1), P (3 kg ha–1 y–1), or a combination of both elements was applied to the vegetation. The fertilization effects turned out to be additive in nature. Adding P decreased the inorganic N concentration and increased the P concentration in the rhizosphere at two sites. Furthermore, P stimulated Sphagnum growth and Sphagnum net primary productivity (NPP) at two sites; it also seemed to encourage growth at two other sites including the moderate-deposition site. Vascular plant growth remained largely unaffected but was depressed at one high-deposition site. Adding N increased the concentration of inorganic N in the rhizosphere at the moderate-deposition site and at two of the three high-deposition sites; vascular plant growth and litter production were encouraged at three high-deposition sites. The addition of N depressed Sphagnum height increment at four high deposition sites and reduced Sphagnum NPP at two sites. Shading by vascular plants was of minor importance in explaining the negative effects of N on Sphagnum. We conclude that because P alleviates the negative impact N has on Sphagnum by enhancing its capability to assimilate the deposited N, P availability is a major factor determining the impact of N deposition on Sphagnum production and thus on carbon sequestration in bogs.
Original languageEnglish
Pages (from-to)793-804
JournalEcosystems
Volume7
Issue number8
DOIs
Publication statusPublished - 2004

Keywords

  • n deposition
  • atmospheric co2
  • growth
  • decomposition
  • vegetation
  • peatlands
  • carbon
  • accumulation
  • competition
  • metabolism

Fingerprint Dive into the research topics of 'How Phosphorus Availability Affects the Impact of Nitrogen Deposition on Sphagnum and Vascular Plants in Bogs'. Together they form a unique fingerprint.

Cite this