Element interactions limit soil carbon storage.
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.
van Groenigen
Kees-Jan
KJ
Department of Plant Sciences, One Shields Avenue, University of California, Davis, CA 95616, USA. cjvangroenigen@ucdavis.edu
Six
Johan
J
Hungate
Bruce A
BA
de Graaff
Marie-Anne
MA
van Breemen
Nico
N
van Kessel
Chris
C
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*
D012987:Soil; D002245:Carbon Dioxide; D002244:Carbon; D009584:Nitrogen