Circum-Arctic release of terrestrial carbon varies between regions and sources

Arctic change is expected to destabilize terrestrial carbon (terrOC) in soils and permafrost, leading to fluvial release, greenhouse gas emission and climate feedback. However, landscape heterogeneity and location-specific observations complicate large-scale assessments of terrOC mobilization. Here...

Full description

Bibliographic Details
Published in:Nature Communications
Main Authors: Martens, Jannik, Wild, Birgit, Semiletov, Igor, Dudarev, Oleg V., Gustafsson, Örjan
Format: Text
Language:English
Published: Nature Publishing Group UK 2022
Subjects:
Online Access:http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9532443/
http://www.ncbi.nlm.nih.gov/pubmed/36195594
https://doi.org/10.1038/s41467-022-33541-0
Description
Summary:Arctic change is expected to destabilize terrestrial carbon (terrOC) in soils and permafrost, leading to fluvial release, greenhouse gas emission and climate feedback. However, landscape heterogeneity and location-specific observations complicate large-scale assessments of terrOC mobilization. Here we reveal differences in terrOC release, deduced from the Circum-Arctic Sediment Carbon Database (CASCADE) using source-diagnostic (δ(13)C-Δ(14)C) and carbon accumulation data. The results show five-times larger terrOC release from the Eurasian than from the American Arctic. Most of the circum-Arctic terrOC originates from near-surface soils (61%); 30% stems from Pleistocene-age permafrost. TerrOC translocation, relative to land-based terrOC stocks, varies by a factor of five between circum-Arctic regions. Shelf seas with higher relative terrOC translocation follow the spatial pattern of recent Arctic warming, while such with lower translocation reflect long-distance lateral transport with efficient remineralization of terrOC. This study provides a receptor-based perspective for how terrOC release varies across the circum-Arctic.