Geospatial patterns in terrestrial organic matter reactivity across four shelf seas spanning the Eurasian Arctic.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 40929280.
- Also identified by DOI 10.1126/sciadv.adt6806 and PMC identifier 12422179.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Organic matter stored in Arctic permafrost represents a key component of the carbon cycle, yet its reactivity across heterogeneous continent-scale permafrost regions remains poorly understood. Here, we leverage the four shelf seas of the Eurasian Arctic as integrative receptor systems to evaluate terrestrial organic matter reactivity, assessed by examining organic carbon preservation as a function of <sup>14</sup>C-constrained cross-shelf transport time. Our findings reveal higher reactivity of terrestrial organic matter released to the Laptev Sea and the eastern East Siberian Sea, lower reactivity in the western East Siberian Sea, and no deducible degradation in the Kara Sea. The reactivity of terrestrial organic matter is primarily determined by the degradation status and composition of its source, alongside potential microbiological controls during transport. This study reveals the heterogeneity of terrestrial organic matter reactivity across the Eurasian Arctic margin and highlights the need for detailed assessments of region-specific carbon release and modeling parameterization.