title: Decoupling the direct and indirect effects of nitrogen deposition on ecosystem function.
abstract: Elevated nitrogen (N) inputs into terrestrial ecosystems are causing major changes to the composition and functioning of ecosystems. Understanding these changes is challenging because there are complex interactions between 'direct' effects of N on plant physiology and soil biogeochemistry, and 'indirect' effects caused by changes in plant species composition. By planting high N and low N plant community compositions into high and low N deposition model terrestrial ecosystems we experimentally decoupled direct and indirect effects and quantified their contribution to changes in carbon, N and water cycling. Our results show that direct effects on plant growth dominate ecosystem response to N deposition, although long-term carbon storage is reduced under high N plant-species composition. These findings suggest that direct effects of N deposition on ecosystem function could be relatively strong in comparison with the indirect effects of plant community change.
authors.affiliation: Natural Environment Research Council Centre for Population Biology, Department of Biological Sciences, Imperial College London, Silwood Park Campus, Ascot, Berkshire SL5 7PY, UK. p.manning@imperial.ac.uk
authors.forename: Pete
authors.initials: P
authors.lastname: Manning
authors.forename: John E
authors.initials: JE
authors.lastname: Newington
authors.forename: Helen R
authors.initials: HR
authors.lastname: Robson
authors.forename: Mark
authors.initials: M
authors.lastname: Saunders
authors.forename: Till
authors.initials: T
authors.lastname: Eggers
authors.forename: Mark A
authors.initials: MA
authors.lastname: Bradford
authors.forename: Richard D
authors.initials: RD
authors.lastname: Bardgett
authors.forename: Michael
authors.initials: M
authors.lastname: Bonkowski
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Ellis
authors.forename: Alan C
authors.initials: AC
authors.lastname: Gange
authors.forename: Susan J
authors.initials: SJ
authors.lastname: Grayston
authors.forename: Ellen
authors.initials: E
authors.lastname: Kandeler
authors.forename: Sven
authors.initials: S
authors.lastname: Marhan
authors.forename: Eileen
authors.initials: E
authors.lastname: Reid
authors.forename: Dagmar
authors.initials: D
authors.lastname: Tscherko
authors.forename: H Charles J
authors.initials: HC
authors.lastname: Godfray
authors.forename: Mark
authors.initials: M
authors.lastname: Rees
mesh_terms: D017753:Ecosystem; D005308:Fertilizers; D009584:Nitrogen / Q000378:metabolism*; D063245:Plant Development; D011157:Population Dynamics; D012987:Soil
chemical_list: D005308:Fertilizers; D012987:Soil; D009584:Nitrogen