title: Element interactions limit soil carbon storage.
abstract: Rising levels of atmospheric CO2 are thought to increase C sinks in terrestrial ecosystems. The potential of these sinks to mitigate CO2 emissions, however, may be constrained by nutrients. By using metaanalysis, we found that elevated CO2 only causes accumulation of soil C when N is added at rates well above typical atmospheric N inputs. Similarly, elevated CO2 only enhances N2 fixation, the major natural process providing soil N input, when other nutrients (e.g., phosphorus, molybdenum, and potassium) are added. Hence, soil C sequestration under elevated CO2 is constrained both directly by N availability and indirectly by nutrients needed to support N2 fixation.
authors.affiliation: Department of Plant Sciences, One Shields Avenue, University of California, Davis, CA 95616, USA. cjvangroenigen@ucdavis.edu
authors.forename: Kees-Jan
authors.initials: KJ
authors.lastname: van Groenigen
authors.forename: Johan
authors.initials: J
authors.lastname: Six
authors.forename: Bruce A
authors.initials: BA
authors.lastname: Hungate
authors.forename: Marie-Anne
authors.initials: MA
authors.lastname: de Graaff
authors.forename: Nico
authors.initials: N
authors.lastname: van Breemen
authors.forename: Chris
authors.initials: C
authors.lastname: van Kessel
mesh_terms: D002244:Carbon / Q000032:analysis* / Q000378:metabolism; D002245:Carbon Dioxide / Q000378:metabolism; D017753:Ecosystem; D017752:Greenhouse Effect; D009584:Nitrogen / Q000032:analysis / Q000378:metabolism; D009586:Nitrogen Fixation; D063245:Plant Development; D010944:Plants / Q000378:metabolism; D012987:Soil / Q000032:analysis*
chemical_list: D012987:Soil; D002245:Carbon Dioxide; D002244:Carbon; D009584:Nitrogen