Decline of fine suspended sediments in the Madeira River Basin (2003–2017)

• Autores: Ayes Rivera, Irma, Armijos Cardenas, Elisa Natalia, Espinoza Villar, Raúl Arnaldo, Espinoza, Jhan Carlo, Molina-Carpio, Jorge, Max Ayala, José, Gutierrez Cori, Omar, Martinez, Jean-Michel, Filizola, Naziano
• Formato: artículo
• Fecha de Publicación: 2019
• Institución: Instituto Geofísico del Perú
• Repositorio: IGP-Institucional
• Lenguaje: español
• OAI Identifier: oai:repositorio.igp.gob.pe:20.500.12816/4279
• Enlace del recurso: http://hdl.handle.net/20.500.12816/4279; https://doi.org/10.3390/w11030514
• Nivel de acceso: acceso abierto
• Materia: Madeira River; Fine suspended sediment concentrations; Water discharge; Hydroelectric dams; http://purl.org/pe-repo/ocde/ford#1.05.00; http://purl.org/pe-repo/ocde/ford#1.05.09

The Madeira River is the second largest Amazon tributary, contributing up to 50% of the Amazon River’s sediment load. The Madeira has significant hydropower potential, which has started to be used by the Madeira Hydroelectric Complex (MHC), with two large dams along the middle stretch of the river. In this study, fine suspended sediment concentration (FSC) data were assessed downstream of the MHC at the Porto Velho gauging station and at the outlet of each tributary (Beni and Mamoré Rivers, upstream from the MHC), from 2003 to 2017. When comparing the pre-MHC (2003–2008) and post-MHC (2015–2017) periods, a 36% decrease in FSC was observed in the Beni River during the peak months of sediment load (December–March). At Porto Velho, a reduction of 30% was found, which responds to the Upper Madeira Basin and hydroelectric regulation. Concerning water discharge, no significant change occurred, indicating that a lower peak FSC cannot be explained by changes in the peak discharge months. However, lower FSCs are associated with a downward break in the overall time series registered at the outlet of the major sediment supplier—the Beni River—during 2010.