Wetland Loss by Erosion in Odiel Marshes (SW Spain)

Wetland loss in many estuaries around the world, has been attributed mainly to undermining and collapse of channel banks. This study aims to quantify bank erosion and vertical erosion/accretion rates on intertidal sediments in the Odiel tidal marshes (SW Spain). Bi-monthly erosion/accretion measurem...

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Detalles Bibliográficos
Autores: Castillo Segura, Jesús Manuel, Rubio Casal, Alfredo Emilio, Luque, Carlos J., Jiménez Nieva, Francisco Javier, Figueroa Clemente, Manuel Enrique
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2002
País:España
Institución:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/96404
Acceso en línea:https://hdl.handle.net/11441/96404
https://doi.org/10.2112/1551-5036-36.sp1.134
Access Level:acceso abierto
Palabra clave:Accretion
Anthropogenic pressure
Bank erosion
Intertidal plain
Spartina maritima
Descripción
Sumario:Wetland loss in many estuaries around the world, has been attributed mainly to undermining and collapse of channel banks. This study aims to quantify bank erosion and vertical erosion/accretion rates on intertidal sediments in the Odiel tidal marshes (SW Spain). Bi-monthly erosion/accretion measurements were taken on eight channels over a four year period, using markers (iron stakes) located on intertidal areas and on eroding banks. The intensity of erosion divides the Odiel marshes into two zones. The northern zone has low erosion rates (horizontal erosion c. -20 cm year-1 and vertical erosion / accretion between 0 and -1 cm year-1), and coincides with low levels of human activities. The southern zone has higher erosion rates (horizontal erosion c. -25 cm year-1 and vertical erosion / accretion between 0 and -5 cm year-1) and exhibits higher levels of anthropogenic pressure. The highest horizontal and vertical erosion rates (c. -80 cm year-1) were recorded on navigation channels. Horizontal and vertical erosion showed a positive linear relationship (r2 = 0.66; P< 0.01), indicating that sediments mobilized by bank erosion are not deposited on adjacent intertidal areas. Erosion led to mature marsh habitat loss of c. 17000 m2 year-1 and a sediment mobilization of c. 16500 m3 year-1.