Recent geomorphological evolution of channel bar in Magdalena River (Colombia) due to natural and anthropogenic interferences

The growing establishment of port structures in estuarine regions has resulted in alternated sedimentation patterns and new geoforms. The primary purpose of this study is to understand the recent formation and geomorphological evolution of the fluvial bar in the final portion of the Magdalena River....

Full description

Autores:
Manzolli, Rogerio Portantiolo
Portz, Luana
Villate-Daza, Diego
Pulido Nossa, Diego Armando
García-Becerra, David
Alcántara-Carrió, Javier
Tipo de recurso:
Article of investigation
Fecha de publicación:
2022
Institución:
Corporación Universidad de la Costa
Repositorio:
REDICUC - Repositorio CUC
Idioma:
eng
OAI Identifier:
oai:repositorio.cuc.edu.co:11323/9976
Acceso en línea:
https://hdl.handle.net/11323/9976
https://repositorio.cuc.edu.co/
Palabra clave:
Fluvial
Bathymetry
Satellite images
Navigation
Sedimentation
Rights
embargoedAccess
License
Atribución-NoComercial-SinDerivadas 4.0 Internacional (CC BY-NC-ND 4.0)
Description
Summary:The growing establishment of port structures in estuarine regions has resulted in alternated sedimentation patterns and new geoforms. The primary purpose of this study is to understand the recent formation and geomorphological evolution of the fluvial bar in the final portion of the Magdalena River. The geomorphological evolution analysis was made possible using Geographic Information Systems tools, satellite images, and bathymetric data. The studied bar formed and stabilized through anthropic and natural factors such as port structures (obstacles to sediment transport), channel morphology, and natural- and anthropic-caused variation to the sediment supply. The lateral bar formation, adjacent to port structures, began in 2017 with surface runoff accumulating and anchored on the riverbank since 2018. At present, the bar covers 45% of the original river width, and an approximate sediment volume worth 4,000,000 m3 has accumulated. Changes in the navigable channel result in slope modification from 2.02° to 5.36°. The construction of port structures, i.e. new pile bridges, changes the natural sediment flow, because they are obstacles, trapping sediments downstream. This period coincides with the end of a weak El Niño cycle, subsequent to a La Nina period also of low intensity, with reduced precipitation rates resulting in a decrease in flow, and therefore contributing to an increase in sedimentation. The observations suggest that it is crucial to understand the channel bars' morphology and origin to avoid possible economic and social impacts due to the disruptions in navigation.