Mots-clés
Action biogène ; Capacité de charge ; Charge solide ; Cours d'eau ; Crustacé ; Ecosystème ; England ; Espèce invasive ; Expérimentation ; Leicestershire ; Lit fluvial ; Royaume-Uni ; Rugosité ; Transport sédimentaire ; ZoogéomorphologieBiogenic process ; Carrying capacity ; Crustacea ; Ecosystem ; England ; Experimentation ; Invasive species ; Leicestershire ; River bed ; Roughness ; Sediment load ; Sediment transport ; Stream ; United Kingdom ; ZoogeomorphologyAcción biógena ; Capacidad de carga ; Carga solida ; Cauce ; Corriente de agua ; Crustáceo ; Ecosistema ; Experimentación ; Inglaterra ; Reino Unido ; Rugosidad ; Transporte sedimentarioIncrease in coarse sediment transport associated with disturbance of gravel river beds by signal crayfish (Pacifastacus leniusculus)
Auteur(s) et Affiliation(s)
JOHNSON, M.F.
Dep. of Geography, Univ., Loughborough, Royaume-Uni
RICE, S.P.
Dep. of Geography, Univ., Loughborough, Royaume-Uni
REID, I.
Dep. of Geography, Univ., Loughborough, Royaume-Uni
Description :
A series of flume experiments, using loose and water-worked gravel beds of narrowly graded grain sizes that were exposed to 6 h of crayfish activity under low-velocity flows, showed a substantial increase in the number of grains entrained by subsequent higher-velocity flows when compared with control runs in which crayfish were never introduced. Crayfish alter the topography of their substrate by constructing pits and mounds, which affect grain protrusion. When walking and foraging, they also alter gravel fabric by reorienting and changing the friction angle of surface grains. The increase in entrainment arising from disturbance by crayfish was shown statistically significant, with grain transport nearly twice as great. This study illustrates further the importance of acknowledging the impact of mobile organisms in conditioning the river bed when assessing sediment entrainment mechanics in the context of predicting bedload flux.
Type de document :
Article de périodique
Source :
Earth surface processes and landforms, issn : 0197-9337, 2011, vol. 36, n°. 12, p. 1680-1692, nombre de pages : 13, Références bibliographiques : 2 p.
Date :
2011
Editeur :
Pays édition : Royaume-Uni, Chichester, Wiley
Langue :
Anglais
Anglais
Droits :
Tous droits réservés © Prodig - Bibliographie Géographique Internationale (BGI)
Tous droits réservés © Prodig - Bibliographie Géographique Internationale (BGI)