Analysis of bedload transport characteristics of Idaho streams and rivers
Carrying capacity ; Grain size distribution ; Idaho ; Model ; Mountain ; Sediment load ; Sediment transport ; Stream ; United States of America
Capacité de charge ; Charge solide ; Cours d'eau ; Etats-Unis ; Granulométrie ; Idaho ; Modèle ; Montagne ; Transport sédimentaire
Data collected for 33 sites on 31 mountain streams and rivers in Central Idaho have enabled the analysis of sediment transport characteristics in streams and rivers with different geological, topographic, morphological, hydrological, hydraulic
, and sedimentological characteristics. The particle size distributions of bedload and bed material, watershed and in-stream characteristics, sediment transport patterns and bedload transport rates are considered in this paper. The obtained results and conclusions
are used to identify different influences on bedload transport rates in analyzed gravel-bed rivers.
A conceptual model for meander initiation in bedload-dominated streams
Bank erosion ; Channel geometry ; Conceptual model ; Meander ; Model ; Sediment transport ; Stream
Cours d'eau ; Erosion des berges ; Géométrie hydraulique ; Modèle ; Modèle conceptuel ; Méandre ; Transport sédimentaire
A simple analytic model is presented relating local sediment transport capacity to variance in the transverse shear stress distribution in a stream channel. The model is used to develop a physically based conceptual model for the initiation
of meandering in straight, bedload-dominated streams as a result of a feedback mechanism.
Assessing potential abiotic and biotic complications of crayfish-induced gravel transport in experimental streams
Biogenic process ; Biomass ; Experimentation ; Fish ; France ; Population dynamics ; Rhône ; Sediment load ; Sediment transport ; Stream
Action biogène ; Biogéomorphologie ; Biomasse ; Charge solide ; Cours d'eau ; Dynamique des populations ; Expérimentation ; France ; Poisson ; Rhône ; Transport sédimentaire
This study used a representative and replicated design of artificial stream experiments to assess how an organism of intermediate size and abundance, a benthic crayfish, affects the transport of gravel across a gradient of an abiotic and a biotic
factor that potentially affect crayfish behaviour, and in turn could complicate the crayfish-induced gravel transport. This study also assesses how crayfish abundance in terms of their biomass affects the gravel transport across a variety of experimental
Capacité de charge ; Cours d'eau ; England ; Géographie physique ; Hydrodynamique ; Modèle ; Pennines ; Royaume-Uni ; Sédimentologie ; Transport sédimentaire
Bedload transport measurements in two upland streams are considered as a function of the excess stream power exerted on the bed by the flow. An inverse depth dependence in the efficiency of the transport process was noted but although bedload
calibre increased as a function of discharge its influence on efficiency could not be demonstrated. However it was suspected that the size-sorting relationships of the bed-material in a number of rivers in relation to the transport efficiency might
Channel flow competence and sediment transport in upland streams in southeast Australia
Australia ; Carrying capacity ; Flood ; Grain size distribution ; New South Wales ; River regime ; Sediment load ; Sediment transport ; Stream ; Stream flow
Australie ; Capacité de charge ; Charge solide ; Cours d'eau ; Crue ; Ecoulement fluvial ; Granulométrie ; New South Wales ; Régime fluvial ; Transport sédimentaire
Bedload transport data from planebed and step-pool reach types are used to determine grain size transport thresholds for selected upland streams in southeast Australia. Morphological differences between the reach types allow the effects
of frictional losses from bedforms, microtopography and bed packing to be incorporated into dimensionless critical shear stress value. Local sediment transport data are also included in a regime model and applied to mountain streams, to investigate whether
empirical data improve the delineation of reach types on the basis of dimensionless discharge per unit width and dimensionless bedload transport.
Geologic influences on fluvial hydrology and bedload transport in small mountainous watersheds, northern New Mexico, USA
Stream power and shear stress estimates derived from bankfull discharge and bed-material size data suggest that higher bedload transport rates and larger bedload particle sizes exist in streams draining crystalline rocks than in streams draining
sedimentary terrane. It appears that source-area lithology, by controlling discharge production, also influences stream power, bedload transport capabilities, and therefore total amounts of bedload transport.
Bed load transport in braided gravel-bed stream models
This paper presents the results of bed load transport measurements from several small-scale gravel braided streams formed at various combinations of slope and constant discharge. These data present an opportunity to investigate the form of sediment
transport relationships for braided streams, assess the extent to which the model results may be directly applicable to field prototypes, and investigate the nature of temporal fluctuations around the mean transport rate.
Dynamics of wood transport in streams : a flume experiment
Carrying capacity ; Experimentation ; Fluvial dynamics ; Japan ; Model ; River bed ; River transport ; Stream ; Stream flow ; Transport ; Wood
Bois ; Capacité de charge ; Cours d'eau ; Dynamique fluviale ; Ecoulement fluvial ; Expérimentation ; Japon ; Lit fluvial ; Modèle ; Transport ; Transport fluvial
The AA. examine some dynamics of wood transport in streams through a series of flume experiments, at the Publish Works Research Institute (PWRI), Tsukuba, Japan, and observe 3 distinct woodtransport regimes : uncongested, congested and semi
of these experiments provide insight into how the depositional fabric of wood accumulations can be used to infer transport dynamics.
Alpes ; Capacité de charge ; Fluviatile ; Granulométrie ; Italie ; Lit fluvial ; Montagne ; Royaume-Uni ; Transport sédimentaire ; Wales
Alps (The) ; Carrying capacity ; Fluvial processes ; Grain size distribution ; Italy ; Mountain ; River bed ; Sediment transport ; United Kingdom ; Wales
The aim of this paper is to describe steep mountain streams in terms of bed morphology, sediment features and sediment transport processes. Field data and observations from Mid-Wales and Eastern Alps streams are reported. Channel morphology
, particle size and shape are investigated in the sediment reaches of bedrock controlled streams. The data relative to 87 bedload samples are reported and the main results discussed in terms of sediment sorting processes.
The concept of sand waves in stream beds is discussed and the principles for their classification examined. The classification divides waves into two grades| the first covers two subdivisions and the second covers six. Each is defined and described
according to its geometrical shape, formation and transportation. (TNC).
Dambreak flood impact on mountain stream bedload transport after 13 years
Carrying capacity ; Catastrophe ; Colorado ; Flood ; Grain size distribution ; Impact ; Mountain ; Sediment transport ; Stream ; United States of America
Capacité de charge ; Catastrophe ; Colorado ; Cours d'eau ; Crue ; Etats-Unis ; Granulométrie ; Impact ; Montagne ; Transport sédimentaire
Studies of the bedload transport regime of the Roaring River, Colorado, in 1984-88, following a dambreak flood in 1982, showed that bedload transport rates were an order of magnitude higher than under pre-flood conditions. Data collected in 1995, 13
years after the flood, are compared with measurements made during 1984-88 to investigate the longer term variation of transport regime. The measurements demonstrate both the control exercised by sediment supply on transport rates and the persistent long
Alpes ; Capacité de charge ; Charge solide ; Cours d'eau ; Détecteur piézoélectrique ; Méthodologie ; Suisse ; Transport sédimentaire
The AA. report on bedload transport observations using piezoelectric bedload impact sensors (PBIS), an indirect method of estimating the volume of bedload transport of coarse sediment. Sediment transport at the Erlenbach stream has been continuously
water discharge, and the critical discharge for the onset of sediment transport.
Carrying capacity ; Fluvial dynamics ; Gravel ; Montana ; Mountain ; Shear stress ; Stream ; Stream flow ; Turbulence ; United States of America
transport events associated with the daily rise and fall in stream discharge were investigated. This paper reports the results of this study designed to describe fully the adjustment of river bed and turbulent flow to the unsteady passage of a pebble bedload.
Coarse bedload transport dynamics are investigated utilizing hydrodynamic and sediment transport data obtained in an extensively instrumented study reach located in Sqaw Creek, Montana, USA. During 1991 and 1992, a number of discrete bedload
Ardenne ; Belgique ; Charge solide ; Contrainte de cisaillement ; Cours d'eau ; Hydrodynamique ; Régime hydrologique ; Traceur ; Transport sédimentaire
Experiments with marked pebbles were carried out on different sized rivers of the Belgian Ardenne (catchment areas varying from less than 1 km2 to 2700 km2). Specific stream power required to cause bedload movement was evaluated and critical values
were obtained. Three types of relationship between critical specific stream power and grain size were established.
Measures of physical heterogeneity in appraisal of geomorphic river condition for urban streams : Twin streams catchment, Auckland, New Zealand
Aquatic ecosystem ; Auckland ; Environmental degradation ; Habitat ; Impact ; New Zealand ; North Island ; Sediment transport ; Stream ; Urban environment ; Urbanization ; Watershed
Auckland ; Bassin-versant ; Cours d'eau ; Dégradation de l'environnement ; Ecosystème aquatique ; Environnement urbain ; Habitat ; Impact ; North Island ; Nouvelle-Zélande ; Transport sédimentaire ; Urbanisation
Analysis was carried out at 27 sites in the Twin Streams catchment in West Auckland. The method successfully recorded the extent of degradation of physical structure following European settlement of the catchment. With the exception of one
subcatchment, streams were found to be largely intact in the headwaters. Geomorphic conditions is more degraded in downstream areas. Fine-grained sediment has smothered stream courses in the lower half of the catchment, covering bed material and creating
Evidence for transport of bedload in waves: analysis of fluvial sediment samples in a small upland stream channel
is relatively independant of the water discharge. Data pertaining to the transport of fluvial sediment sampled in detail during a five hour long event in a small upland stream channel in the extremely arid southern Negev are presented.
In extremely arid, rocky, high relief watersheds, coarse fluvial sediment, if initially entrained, tends to group itself in well defined waves which move discretly downstream. Above a certain threshold determined by stream power this movement
Bedload tansport during rising and falling stages on two small streams
Gravel ; Ground survey ; Hydrodynamics ; Methodology ; Mississippi ; River bed ; Roughness ; Sediment load ; Stream ; United States
The A. has analysed bed load transport rates during rising and falling stages of two small streams (Godwin Creek Research Watershed, Nothern Mississippi, USA)