The undetected loss of aged carbon from boreal mineral soils.

ABSTRACT: The boreal forest is among the largest terrestrial biomes on earth, storing more carbon (C) than the atmosphere. Due to rapid climatic warming and enhanced human development, the boreal region may have begun transitioning from a net C sink to a net source. This raises serious concern that old biogenic soil C can be re-introduced into the modern C cycle in near future. Combining bio-decay experiments, mixing models and the Keeling plot method, we discovered a distinct old pre-bomb organic carbon fraction with high biodegradation rate. In total, 34 ± 12% of water-extractable organic carbon (WEOC) in podzols, one of the dominating boreal soil types, consisted of aged (~ 1000 year) labile C. The omission of this aged (i.e., Δ¹⁴C depleted) WEOC fraction in earlier studies is due to t

SUBMITTER: Hensgens G 

PROVIDER: S-EPMC7973788 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature