Particle Triggered Reactions as an Important Mechanism of Alkalinity and Inorganic Carbon Removal in River Plumes

Eyal Wurgaft, Z. A. Wang, J. H. Churchill, T. Dellapenna, S. Song, J. Du, M. C. Ringham, T. Rivlin, B. Lazar

Research output: Contribution to journalArticlepeer-review


The effects of heterogeneous reactions between river-borne particles and the carbonate system were studied in the plumes of the Mississippi and Brazos rivers. Measurements within these plumes revealed significant removal of dissolved inorganic carbon (DIC) and total alkalinity (TA). After accounting for all known DIC and TA sinks and sources, heterogeneous reactions (i.e., heterogeneous CaCO3 precipitation and cation exchange between adsorbed and dissolved ions) were found to be responsible for a significant fraction of DIC and TA removal, exceeding 10% and 90%, respectively, in the Mississippi and Brazos plume waters. This finding was corroborated by laboratory experiments, in which the seeding of seawater with the riverine particles induced the removal of the DIC and TA. The combined results demonstrate that heterogeneous reactions may represent an important controlling mechanism of the seawater carbonate system in particle-rich coastal areas and may significantly impact the coastal carbon cycle.

Original languageEnglish
Article numbere2021GL093178
JournalGeophysical Research Letters
Issue number11
StatePublished - Jun 2021

Bibliographical note

Funding Information:
We are indebted to the captain and crew of the R/V Pelican for their assistance during the cruise. We thank Alex Ren from the Louisiana Universities Marine Consortium for his help before and after the cruise and Chana Krenzler for reading and commenting on the first draft. This research was funded by the National Science Foundation (NSF) and the Bi‐National Science Foundation U.S‐Israel award number OCE‐BSF 1635388.

Publisher Copyright:
© 2021. American Geophysical Union. All Rights Reserved.


  • calcium carbonate
  • carbon cycle
  • carbonate chemistry
  • heterogeneous reactions
  • Mississippi
  • river mouths


Dive into the research topics of 'Particle Triggered Reactions as an Important Mechanism of Alkalinity and Inorganic Carbon Removal in River Plumes'. Together they form a unique fingerprint.

Cite this