A Dimensionless Framework for the Partitioning of Fluvial Inorganic Carbon

Sammanfattning

Rivers are pivotal in the global carbon cycle, transporting terrestrial carbon to the ocean while emitting significant amount of CO2 to the atmosphere. However, the partitioning of fluvial inorganic carbon (IC) between downstream transport and atmospheric evasion remains uncertain due to intricate hydrodynamic and biogeochemical processes. Inspired by Budyko's hydrological work, this study introduces a dimensionless framework to identify critical factors in fluvial IC partitioning: the IC fraction in equilibrium with the atmosphere and the ratio of advection to evasion timescales. River catchment analyses and modeling reveal that the equilibrium ratio determines the fraction of IC stably transported downstream. The hydrodynamic-driven timescale ratio determines the fate of out-of-equilibrium IC, with low-order streams favoring atmospheric evasion and higher-order streams promoting downstream transport. This framework provides a simple yet robust approach to predicting river carbon dynamics, with implications for land-to-ocean transport, fluvial emissions, and climate mitigation strategies such as enhanced weathering.

Nyckelord

carbon; rivers; CO2 emissions; water chemistry; turbulence

Publicerad i

Geophysical Research Letters
2024, volym: 51, nummer: 19, artikelnummer: e2024GL111310
Utgivare: AMER GEOPHYSICAL UNION

SLU författare

• Yan, Yanzi

  • Institutionen för mark och miljö, Sveriges lantbruksuniversitet
    

UKÄ forskningsämne

Multidisciplinär geovetenskap

Publikationens identifierare

• DOI: https://doi.org/10.1029/2024GL111310

Permanent länk till denna sida (URI)

https://res.slu.se/id/publ/140150