Articles | Volume 20, issue 24
https://doi.org/10.5194/bg-20-4981-2023
© Author(s) 2023. 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-20-4981-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Influence of a small submarine canyon on biogenic matter export flux in the lower St. Lawrence Estuary, eastern Canada
Department of Earth Sciences, University of New Brunswick (UNB), Fredericton, E3B 5A3, Canada
Michel Gosselin
Institut des sciences de la mer de Rimouski (ISMER), Université du Québec à Rimouski (UQAR), Rimouski, G5L 3A1, Canada
Catherine Lalande
Amundsen Science, Université Laval, Quebec City, G1V 0A6, Canada
Alexandre Normandeau
Geological Survey of Canada (Atlantic), Bedford Institute of Oceanography, Dartmouth, B2Y 4A2, Canada
Jean-Carlos Montero-Serrano
Institut des sciences de la mer de Rimouski (ISMER), Université du Québec à Rimouski (UQAR), Rimouski, G5L 3A1, Canada
Khouloud Baccara
Institut des sciences de la mer de Rimouski (ISMER), Université du Québec à Rimouski (UQAR), Rimouski, G5L 3A1, Canada
Daniel Bourgault
Institut des sciences de la mer de Rimouski (ISMER), Université du Québec à Rimouski (UQAR), Rimouski, G5L 3A1, Canada
Owen Sherwood
Department of Earth and Environmental Sciences, Dalhousie University, Halifax, B3H 4R2, Canada
Department of Earth Sciences, University of New Brunswick (UNB), Fredericton, E3B 5A3, Canada
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Short summary
We studied the impact of submarine canyon processes within the Pointe-des-Monts system on biogenic matter export and phytoplankton assemblages. Using data from three oceanographic moorings, we show that the canyon experienced two low-amplitude sediment remobilization events in 2020–2021 that led to enhanced particle fluxes in the deep-water column layer > 2.6 km offshore. Sinking phytoplankton fluxes were lower near the canyon compared to background values from the lower St. Lawrence Estuary.
We studied the impact of submarine canyon processes within the Pointe-des-Monts system on...
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