Articles | Volume 22, issue 10
https://doi.org/10.5194/bg-22-2403-2025
© Author(s) 2025. 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-22-2403-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
27 May 2025
Research article |
| 27 May 2025
| 27 May 2025
Biogeochemical functioning of Lake Alaotra (Madagascar): a reset of aquatic carbon sources along the land–ocean aquatic continuum
Vao Fenotiana Razanamahandry
CORRESPONDING AUTHOR
Department of Earth and Environmental Sciences, KU Leuven, Leuven, Belgium
Alberto Vieira Borges
Chemical Oceanography Unit, University of Liège, Liège, Belgium
Liesa Brosens
Environmental Modeling Unit, Flemish Institute for Technological Research (VITO), Mol, Belgium
Cedric Morana
Chemical Oceanography Unit, University of Liège, Liège, Belgium
Tantely Razafimbelo
Laboratoire des Radio-Isotopes, University of Antananarivo, Antananarivo, Madagascar
Tovonarivo Rafolisy
Laboratoire des Radio-Isotopes, University of Antananarivo, Antananarivo, Madagascar
Gerard Govers
Department of Earth and Environmental Sciences, KU Leuven, Leuven, Belgium
Steven Bouillon
CORRESPONDING AUTHOR
Department of Earth and Environmental Sciences, KU Leuven, Leuven, Belgium
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Short summary
A comprehensive survey of the biogeochemistry of the Lake Alaotra system showed that the lake and surrounding wetlands acted as a substantial source of new organic carbon (OC), which was exported downstream. Marsh vegetation was the main source of dissolved OC, while phytoplankton contributed to the particulate OC pool. The biogeochemical functioning of Lake Alaotra differs from most East African lakes studied, likely due to its large surface area, shallow water depth, and surrounding wetlands.
A comprehensive survey of the biogeochemistry of the Lake Alaotra system showed that the lake...
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