Drivers and impacts of sediment deposition in Amazonian floodplains
The Amazon River carries enormous amounts of sediment from the Andes mountains, much of which is deposited in its floodplains. However, accurate quantification of the sediment sink at fine spatiotemporal scales is still challenging. Here, we present a high-resolution hydrodynamic-sediment model to simulate sediment deposition in a representative Amazon/Solimões floodplain. The process is found to be jointly driven by inundation, suspended sediment concentration in the Amazon River, and floodplain hydrodynamics and only weakly correlated with inundation level. By upscaling the sediment deposition rate (1.33 ± 0.24 kg m<sup>-2</sup> yr<sup>-1</sup>), we estimate the trapping of 77.3 ± 13.9 Mt (or 6.1 ± 1%) of the Amazon River sediment by the Amazon/Solimões floodplains every year. Widespread deforestation would reduce the trapping efficiency of the floodplains over time, exacerbating downstream river aggradation. Additionally, we show that the deposition of sediment-associated organic carbon plays a minor role in fueling carbon dioxide and methane emissions in the Amazon.
Authors
- Sébastien Pinel (ORCID: https://orcid.org/0000-0001-9608-754X)
- Dongyu Feng (ORCID: https://orcid.org/0000-0001-7273-3033)
- Donghui Xu (ORCID: https://orcid.org/0000-0002-2859-2664)
- J. H. Amaral (ORCID: https://orcid.org/0000-0002-8992-6082)
- Marie‐Paule Bonnet
- Gautam Bisht (ORCID: https://orcid.org/0000-0001-6641-7595)
- Alice César Fassoni‐Andrade (ORCID: https://orcid.org/0000-0002-3233-8781)
- Zeli Tan (ORCID: https://orcid.org/0000-0001-5958-2584)
Institutions
- Universidade Federal do Rio Grande do Sul (BR)
- Richland College (US)
- Pacific Northwest National Laboratory (US)
- Universidade de Brasília (BR)
- Université de Perpignan (FR)
- Université de Montpellier (FR)
- Acteurs, Ressources et Territoires dans le Développement (FR)
- Centre de Formation et de Recherche sur les Environnements Méditerranéens (FR)
- Institute of Vegetables and Flowers (CN)
- Institut de Recherche pour le Développement (FR)
- UMR Espace-Dev
- Universidad del Rosario (CO)
Publication Details
- Journal
- Nature Communications
- Published
- 2025-04-02
- DOI
- https://doi.org/10.1038/s41467-025-57495-1
- Citations
- 12
- Primary Topic
- Soil erosion and sediment transport
- Type
- article
- Field-Weighted Citation Impact
- 14.23
Funders
- U.S. Department of Energy
- Battelle
- Ministério da Ciência, Tecnologia e Inovação
- Conselho Nacional de Desenvolvimento Científico e Tecnológico
- Office of Science
- Biological and Environmental Research
- Pacific Northwest National Laboratory