Effect of changes in fine-grained matrix on bedload sediment transport in a gravel-bed river

Auteur(s) et Affiliation(s)



Description :
A recent increase of a fine-grained matrix in the bed of Nahal Eshtemoa, an ephemeral river of the northern Negev, has more than doubled the boundary shear stress needed to initiate bedload. The relation between bedload flux and boundary shear stress continues to be well-defined, but it is displaced. The matrix now contains a significant amount of silt and clay size material. The reasons for the increased entrainment threshold of bedload are explored. Large-scale laser scanning of the dry bed reveals a reduction in grain-scale morphological roughness, while artificial in situ tests of matrix integrity indicate considerable cohesion. The implications for adopting bed material sampling strategies that account for matrix development are assessed.


Type de document :
Article de périodique

Source :
Earth surface processes and landforms, issn : 0197-9337, 2013, vol. 38, n°. 5, p. 441-448, nombre de pages : 8, Références bibliographiques : 1 p.

Date :
2013

Editeur :
Pays édition : Royaume-Uni, Chichester, Wiley