title: Grassland responses to global environmental changes suppressed by elevated CO2.
abstract: Simulated global changes, including warming, increased precipitation, and nitrogen deposition, alone and in concert, increased net primary production (NPP) in the third year of ecosystem-scale manipulations in a California annual grassland. Elevated carbon dioxide also increased NPP, but only as a single-factor treatment. Across all multifactor manipulations, elevated carbon dioxide suppressed root allocation, decreasing the positive effects of increased temperature, precipitation, and nitrogen deposition on NPP. The NPP responses to interacting global changes differed greatly from simple combinations of single-factor responses. These findings indicate the importance of a multifactor experimental approach to understanding ecosystem responses to global change.
authors.affiliation: Department of Global Ecology, Carnegie Institution of Washington, 260 Panama Street, Stanford, CA 94305, USA. shaw@globalecology.stanford.edu
authors.forename: M Rebecca
authors.initials: MR
authors.lastname: Shaw
authors.forename: Erika S
authors.initials: ES
authors.lastname: Zavaleta
authors.forename: Nona R
authors.initials: NR
authors.lastname: Chiariello
authors.forename: Elsa E
authors.initials: EE
authors.lastname: Cleland
authors.forename: Harold A
authors.initials: HA
authors.lastname: Mooney
authors.forename: Christopher B
authors.initials: CB
authors.lastname: Field
mesh_terms: D001272:Atmosphere; D018533:Biomass; D002140:California; D002245:Carbon Dioxide; D002980:Climate; D017753:Ecosystem; D004777:Environment; D031314:Geraniaceae / Q000254:growth & development*; D006109:Poaceae / Q000254:growth & development*; D012987:Soil; D013696:Temperature; D014887:Weather
chemical_list: D012987:Soil; D002245:Carbon Dioxide