Skip navigation
Skip navigation

Maintenance of leaf N controls the photosynthetic CO2 response of grassland species exposed to 9 years of free-air CO2 enrichment

Crous, Kristine; Reich, Peter B; Hunter, Mark D; Ellsworth, David S

Description

Determining underlying physiological patterns governing plant productivity and diversity in grasslands are critical to evaluate species responses to future environmental conditions of elevated CO2 and nitrogen (N) deposition. In a 9-year experiment, N was added to monocultures of seven C3 grassland species exposed to elevated atmospheric CO2 (560 μmol CO2 mol-1) to evaluate how N addition affects CO2 responsiveness in species of contrasting functional groups. Functional groups differed in their...[Show more]

dc.contributor.authorCrous, Kristine
dc.contributor.authorReich, Peter B
dc.contributor.authorHunter, Mark D
dc.contributor.authorEllsworth, David S
dc.date.accessioned2015-12-10T23:07:55Z
dc.identifier.issn1354-1013
dc.identifier.urihttp://hdl.handle.net/1885/63064
dc.description.abstractDetermining underlying physiological patterns governing plant productivity and diversity in grasslands are critical to evaluate species responses to future environmental conditions of elevated CO2 and nitrogen (N) deposition. In a 9-year experiment, N was added to monocultures of seven C3 grassland species exposed to elevated atmospheric CO2 (560 μmol CO2 mol-1) to evaluate how N addition affects CO2 responsiveness in species of contrasting functional groups. Functional groups differed in their responses to elevated CO2 and N treatments. Forb species exhibited strong down-regulation of leaf Nmass concentrations (-26%) and photosynthetic capacity (-28%) in response to elevated CO2, especially at high N supply, whereas C3 grasses did not. Hence, achieved photosynthetic performance was markedly enhanced for C3 grasses (+68%) in elevated CO2, but not significantly for forbs. Differences in access to soil resources between forbs and grasses may distinguish their responses to elevated CO2 and N addition. Forbs had lesser root biomass, a lower distribution of biomass to roots, and lower specific root length than grasses. Maintenance of leaf N, possibly through increased root foraging in this nutrient-poor grassland, was necessary to sustain stimulation of photosynthesis under long-term elevated CO2. Dilution of leaf N and associated photosynthetic down-regulation in forbs under elevated [CO2], relative to the C3 grasses, illustrates the potential for shifts in species composition and diversity in grassland ecosystems that have significant forb and grass components.
dc.publisherBlackwell Publishing Ltd
dc.sourceGlobal Change Biology
dc.subjectKeywords: angiosperm; carbon cycle; carbon dioxide enrichment; grassland; nitrogen cycle; photosynthesis; species diversity; Poaceae C3 grass species; Carboxylation rate; FACE; Free-air CO2; Nitrogen; Photosynthesis; Species functional groups
dc.titleMaintenance of leaf N controls the photosynthetic CO2 response of grassland species exposed to 9 years of free-air CO2 enrichment
dc.typeJournal article
local.description.notesImported from ARIES
local.identifier.citationvolume2009
dc.date.issued2009
local.identifier.absfor060705 - Plant Physiology
local.identifier.ariespublicationu9204316xPUB765
local.type.statusPublished Version
local.contributor.affiliationCrous, Kristine, College of Medicine, Biology and Environment, ANU
local.contributor.affiliationReich, Peter B, University of Minnesota
local.contributor.affiliationHunter, Mark D, University of Michigan
local.contributor.affiliationEllsworth, David S, University of Western Sydney
local.description.embargo2037-12-31
local.bibliographicCitation.startpage1
local.bibliographicCitation.lastpage13
local.identifier.doi10.1111/j.1365-2486.2009.02058.x
dc.date.updated2016-02-24T11:53:56Z
local.identifier.scopusID2-s2.0-77954153366
CollectionsANU Research Publications

Download

File Description SizeFormat Image
01_Crous_Maintenance_of_leaf_N_controls_2009.pdf265.72 kBAdobe PDF    Request a copy


Items in Open Research are protected by copyright, with all rights reserved, unless otherwise indicated.

Updated:  19 May 2020/ Responsible Officer:  University Librarian/ Page Contact:  Library Systems & Web Coordinator