Experimental study of the response of a gravel streambed to increased sediment supply

Auteur(s) et Affiliation(s)



Description :
The AA. report on an experiment in a field-scale flume in which sediment supply is increased to a gravel bed with alternate bars. Sediment was recirculated in the experiments, but augmented in 2 steps, after which the bed was allowed to reach a new steady state. The transport rate at the end of the experiment was 3 times larger than at the start. High-resolution sediment flux and topographic measurements, grain size derived from photographs, and hydrodynamic modeling allow to document the topographic and textural response of the bed to increased sediment supply. The spatial patterns of bed topography and texture were forced by the flume setup and the initial and final steady states included long stationary alternate bars with associated grain size sorting. Bed topography and textural patterns adjusted to increased sediment supply over different timescales. Adjustments in local topography and sorting, primarily in the form of smaller, migrating bars, continued for a period approximately equal to that required to initially reach transport steady state.


Type de document :
Article de périodique

Source :
Earth surface processes and landforms, issn : 0197-9337, 2013, vol. 38, n°. 14, p. 1748-1764, nombre de pages : 17, Références bibliographiques : 1 p.

Date :
2013

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