Articles | Volume 23, issue 16
https://doi.org/10.5194/bg-23-5901-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-23-5901-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
26 Aug 2026
Research article |
| 26 Aug 2026
| 26 Aug 2026
Qualitative transformations of dissolved organic matter along supra-permafrost flow: insights from Arctic subterranean estuaries
Aude Flamand
Institut des Sciences de la Mer de Rimouski (ISMER), Université du Québec à Rimouski (UQAR), 310 Allée des Ursulines, Rimouski, Québec, G5L 3AL, Canada
Groupe de recherche Québec-Océan, Québec City, Canada
Département de Sciences Biologiques, Université de Montréal, 1375 Avenue Thérèse-Lavoie-Roux, Montréal, Québec, H2V 0B3, Canada
Groupe de Recherche Interuniversitaire en Limnologie (GRIL), Montréal, Canada
Jean-François Lapierre
Département de Sciences Biologiques, Université de Montréal, 1375 Avenue Thérèse-Lavoie-Roux, Montréal, Québec, H2V 0B3, Canada
Groupe de Recherche Interuniversitaire en Limnologie (GRIL), Montréal, Canada
Gwénaëlle Chaillou
CORRESPONDING AUTHOR
Institut des Sciences de la Mer de Rimouski (ISMER), Université du Québec à Rimouski (UQAR), 310 Allée des Ursulines, Rimouski, Québec, G5L 3AL, Canada
Groupe de recherche Québec-Océan, Québec City, Canada
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Short summary
Climate change is accelerating permafrost thaw and coastal erosion, increasing dissolved organic matter (DOM) inputs to the Arctic Ocean. We show that, beyond seawater dilution, DOM is transformed as it passes through Arctic beach subterranean estuaries, shifting from humic-rich to more microbially processed material. These coastal zones act as biogeochemical reactors, modifying DOM before its export to coastal waters.
Climate change is accelerating permafrost thaw and coastal erosion, increasing dissolved organic...
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