Characteristics of log and clast bed-steps in step-pool streams of northwestern Montana, USA

Auteur(s) et Affiliation(s)



Description :
The role of log and clast steps was studied in 53 step-pool reaches in 32 streams in northwestern Montana. In each reach, 20 consecutive steps were sampled. No significant difference exists between clast and log steps with regard to step spacing and step height. This suggested either that 1) woody debris is mobile in even the smallest channels in the study area, or 2) channel flows arrange clast steps around immobile woody debris. Calculations of flow resistance suggest that most steps serve to maximize flow resistance. These results support the second hypothesis, that the height and spacing of clast steps are adjusted around immobile log steps to maintain consistent step characteristics.


Type de document :
Article de périodique

Source :
Geomorphology (Amsterdam), issn : 0169-555X, 1997, vol. 20, n°. 1-2, p. 1-10, Collation : Illustration, Références bibliographiques : 26 ref.

Date :
1997

Editeur :
Pays édition : Pays-Bas, Amsterdam, Elsevier