title: Roots and associated fungi drive long-term carbon sequestration in boreal forest.
abstract: Boreal forest soils function as a terrestrial net sink in the global carbon cycle. The prevailing dogma has focused on aboveground plant litter as a principal source of soil organic matter. Using (14)C bomb-carbon modeling, we show that 50 to 70% of stored carbon in a chronosequence of boreal forested islands derives from roots and root-associated microorganisms. Fungal biomarkers indicate impaired degradation and preservation of fungal residues in late successional forests. Furthermore, 454 pyrosequencing of molecular barcodes, in conjunction with stable isotope analyses, highlights root-associated fungi as important regulators of ecosystem carbon dynamics. Our results suggest an alternative mechanism for the accumulation of organic matter in boreal forests during succession in the long-term absence of disturbance.
authors.affiliation: Department of Forest Mycology and Plant Pathology, Uppsala BioCenter, Swedish University of Agricultural Sciences, Uppsala, Sweden. karina.clemmensen@slu.se
authors.forename: K E
authors.initials: KE
authors.lastname: Clemmensen
authors.forename: A
authors.initials: A
authors.lastname: Bahr
authors.forename: O
authors.initials: O
authors.lastname: Ovaskainen
authors.forename: A
authors.initials: A
authors.lastname: Dahlberg
authors.forename: A
authors.initials: A
authors.lastname: Ekblad
authors.forename: H
authors.initials: H
authors.lastname: Wallander
authors.forename: J
authors.initials: J
authors.lastname: Stenlid
authors.forename: R D
authors.initials: RD
authors.lastname: Finlay
authors.forename: D A
authors.initials: DA
authors.lastname: Wardle
authors.forename: B D
authors.initials: BD
authors.lastname: Lindahl
mesh_terms: D015415:Biomarkers / Q000378:metabolism; D057486:Carbon Cycle; D002250:Carbon Radioisotopes / Q000378:metabolism; D004875:Ergosterol / Q000378:metabolism; D005658:Fungi / Q000378:metabolism*; D005944:Glucosamine / Q000378:metabolism; D018517:Plant Roots / Q000378:metabolism* / Q000382:microbiology*; D012987:Soil; D014197:Trees / Q000378:metabolism* / Q000382:microbiology*
chemical_list: D015415:Biomarkers; D002250:Carbon Radioisotopes; D012987:Soil; D005944:Glucosamine; D004875:Ergosterol