title: Impacts of fine root turnover on forest NPP and soil C sequestration potential.
abstract: Estimates of forest net primary production (NPP) demand accurate estimates of root production and turnover. We assessed root turnover with the use of an isotope tracer in two forest free-air carbon dioxide enrichment experiments. Growth at elevated carbon dioxide did not accelerate root turnover in either the pine or the hardwood forest. Turnover of fine root carbon varied from 1.2 to 9 years, depending on root diameter and dominant tree species. These long turnover times suggest that root production and turnover in forests have been overestimated and that sequestration of anthropogenic atmospheric carbon in forest soils may be lower than currently estimated.
authors: Environmental Research Division, Argonne National Laboratory, Argonne, IL 60439, USA. matamala@anl.gov
authors: Roser
authors: R
authors: Matamala
authors: Miquel A
authors: MA
authors: Gonzàlez-Meler
authors: Julie D
authors: JD
authors: Jastrow
authors: Richard J
authors: RJ
authors: Norby
authors: William H
authors: WH
authors: Schlesinger
mesh_terms: D001272:Atmosphere; D018533:Biomass; D002244:Carbon / Q000032:analysis* / Q000378:metabolism; D002245:Carbon Dioxide / Q000378:metabolism; D002247:Carbon Isotopes / Q000032:analysis; D017753:Ecosystem; D031317:Liquidambar / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*; D009657:North Carolina; D041603:Pinus taeda / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*; D018517:Plant Roots / Q000737:chemistry / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*; D012621:Seasons; D012987:Soil / Q000032:analysis*; D013714:Tennessee; D013997:Time Factors; D014197:Trees
chemical_list: D002247:Carbon Isotopes; D012987:Soil; D002245:Carbon Dioxide; D002244:Carbon