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  • The influence of microform bed roughness elements on flow and sediment transport in gravel bed rivers : comment on a paper by Marwan A. Hassan and Ian Reid
  • The purpose of this discussion is two-fold : 1) to provide a further demonstration of the importance of treating the bedform-flow resistance-sediment transport system in a gravel-bed river as a dynamic interaction, as has been the case for many
  • years in the context of sand-bed rivers; and 2) to emphasize the importance of understanding this interaction and the feedback that controls it in terms of the characteristics of near-bed turbulence.
  • Process-based model of grain lifting from river bed to estimate suspended-sediment concentration in a small headwater basin
  • Grain size distribution ; Hokkaido ; Japan ; Meltwater ; Model ; Pic discharge ; River bed ; Sand ; Suspended load ; Watershed
  • Suspended sediment is supplied from river bed sediment in Hiyamizusawa Brook, Hokkaido, Japan, during the snowmelt season. The stirring up of fine grains from the river bed is an important control of the time variation of suspended-sediment flux
  • . A model previously used to explain the stirring up of fine grains within a cobble and pebble bed is applied to a sand bed, with a modification . Consequently, the amount of fine material stirred up from the river bed is estimated from the grain size
  • distribution of river bed sediment, and the suspended flux is thus calculated. The results were equivalent to the field data.
  • The influence of microform bed roughness elements on flow and sediment transport in gravel bed rivers : a reply
  • Carrying capacity ; Flood ; Flow ; Fluvial hydrology ; Fluvial processes ; River bed ; Sediment transport ; Turbulence
  • Fluvial geomorphology : initial motion of bed material in gravel-bed rivers
  • Longitudinal changes in size and sorting of stream beds material in four English Rivers
  • Breakup and reestablishment of the armour layer in a large gravel-bed river below dams : the lower Ebro
  • Carrying capacity ; Dam ; Ebro ; Flood ; Grain size distribution ; Hydraulic works ; River bed ; Spain ; Stream
  • This paper describes the breakup and the reestablishment of the bed armour layer in the regulated gravel-bed Ebro River during a flooding period. The study was conducted over a 28-km study reach from 2002 to 2004. The surface, subsurface and bed
  • load grain size distribution constitute the bases for the analysis of bed-armouring dynamics. The results indicate that the magnitude of floods controlled the degree of armouring of the river bed. The supply and transport of bed material appear
  • to be in balance in the river reach immediately below the dam.
  • Wandering gravel-bed rivers
  • Ce court article caractérise le phénomène courant dans la région cordillère de l'ouest canadien des wandering gravel-bed rivers . - (C. Risi).
  • Some thermodynamic criteria for river channel changes
  • Fluvial dynamics ; Geosystem ; River bed ; Spatial variation ; Stream ; Stream flow
  • A theoretical model of river channel changes is presented, which shows some nonequilibrium thermodynamic criteria of a river channel to bedding and equilibrium.
  • Braided channel ; Carrying capacity ; Channel geometry ; Comparative study ; Cross section ; Discriminant analysis ; Fluvial dynamics ; Longitudinal section ; Mathematical model ; Meander ; Model ; River bed ; Roughness ; Slope gradient ; Stream
  • The classic channel slope-discharge relationship proposed by Leopold and Wolman (1957) for channel pattern discrimination has been tested by a large database including 4 types of rivers : gravel-bed meandering rivers, gravel-bed braided rivers, sand
  • -bed meandering rivers and sand-bed braided rivers. The result shows that this relationship cannot discriminate channel patterns well when both gravel- and sand-bed rivers are considered. The channel width-bankfull discharge relationship suggested by XU
  • (1996) for discrimination of channel patterns of sand-bed rivers in China, is also tested in this study by the same database. Discussion of the results.
  • Scour chain employment in gravel bed rivers
  • Australia ; Carrying capacity ; Fluvial processes ; Hydrodynamics ; Methodology ; New South Wales ; River bed
  • The dynamics of river beds can be assessed from scour and fill data obtained from scour chains. Chain insertion, anchoring and relocation can be determined with minimal manpower by utilising a set of tested employment methodologies
  • . These are described in sufficient detail to allow fluvial geomorphologists, ecologists and river engineers to more commonly utilise chains in studies of river stability and river response.
  • Fluvial geomorphology : structured beds in gravelly rivers
  • Bibliography ; Carrying capacity ; Fluvial processes ; Gravel ; Hydrodynamics ; River bed ; Sediment transport ; Sedimentology ; Turbulence
  • This progress report reviews the research into the processes of : 1) coarse surface layers; 2) armour versus pavement; 3) bed surface structure and sediment transport; 4) imbrication; 5) small- and medium-scale gravel bedforms; 6) gravel bedforms
  • Discrimination of channel patterns for gravel- and sand-bed rivers
  • Braided channel ; Discriminant analysis ; Gravel ; Meander ; River bed ; Runoff ; Sand ; Shear stress ; Stream ; Stream flow
  • Based on data from around 200 alluvial rivers in several countries, a systematic comparison of flow shear stress and stream power has been made between sand- and gravel-bed rivers. The formation of channel pattern can be regarded as the outcome
  • of sediment transport and channel bank constraints in an alluvial river. To overcome the difficulty of quantifying channel bank constraints, channel width/depth ratio and a dimensionless channel width index are used to reflect it indirectly.
  • Underlying gravel layers in a large sand bed river and their influence on downstream-dam channel adjustment
  • Bank erosion ; Channel geometry ; China ; Dam ; Fluvial erosion ; Gravel ; Hydraulic works ; Longitudinal section ; River bed ; Stream
  • In this paper, a study is made based on data from the Hanjiang River, the longest tributary of the Yangtze River in China. This example demonstrates the significance of the study of the underlying gravel layers in sand-bed rivers in relation
  • Measurement of bedload in rivers in Erosion and sediment yield : some methods of measurement and modelling.
  • Only in recent years have bed load data for rivers existed in sufficient quantity and reliability to facilitate a better understanding of the bedload transport process. Data for the East Fork River, Wyoming indicate that when sand-size particles
  • are dominant as bedload the bed load accounts for about half the total load. The examples of the Tanana, Snake and Clearwater Rivers indicate that for gravel bed rivers the bed load probably accounts for less than 10 % of the total load.
  • Downstream variation in bed sediment size along the East Carpathian rivers : evidence of the role of sediment sources
  • Carpathian Mountains ; Drainage network ; Grain size distribution ; River bed ; Romania ; Sediment budget ; Sediment load ; Sedimentology ; Stream ; Suspended load
  • This paper intends to approach the phenomena of river-bed material variability inside a network of rivers from the drainage basin of Siret as a link between sediment sources and their sediment delivery. The AA. will focus on the spatial variability
  • of the distribution types of river-bed material and will try to moot the origin of bimodality of river-bed deposits. As opposed to its tributaries, the source of the first mode, of gravel, is allochtonous to the Siret river, generated by the massive input of coarse
  • Persistence of the surface texture of a gravel-bed river during a large flood
  • Channel geometry ; Colorado ; Flood ; Grain size distribution ; Gravel ; Meander ; Meltwater ; Pic discharge ; River bed ; Stream ; United States of America
  • The goal of this paper is to clarify conditions under which the surface layer of a gravel-bed river may persist during large floods. Detailed field measurements of channel topography and bed surface grain size were made in a gravel-bed reach
  • of time. During the 2003 peak flow, the river avulsed immediately upstream of the sudy reach. The abandonment was rapid, leaving the bed texture essentially frozen in place.
  • of the Colorado River prior to a flood in 2003. Runoff produced during the 2003 snowmelt was far above average, resulting in a sustained period of high flow with a peak discharge; all available grain sizes within the study reach were mobilized in this period
  • Evaluating bed-material transport equations using field measurements in a sandy gravel-bed stream, Arbúcies River, NE Spain
  • Bed-material load under a wide range of hydraulic conditions was sampled in a poorly sorted, sandy, gravel-bed river (Arbúcies, NE Spain) during 1991 and 1992. The Arbúcies data showed a marked scatter of bed-material discharges, reflecting the high
  • variability of bedload rates as well as of suspended concentrations. Bed-material discharges were used to test 5 bedload and bed-material formulae. The degree of agreement between observed and predicted values varies greatly.
  • Developments in monitoring and modelling small-scale river bed topography
  • Fluvial dynamics ; Fluvial processes ; Mountain ; Numerical model ; Photogrammetry ; River bed ; Switzerland ; Topography ; Valais
  • This paper presents a detailed assessment of the distributed monitoring and terrain modelling of river bed topography using a technique that combines rigorous analytical photogrammetry with rapid ground survey. A detailed assessment is undertaken
  • of the quality of the morphological information acquired. This allow some general comments to be made concerning the use of more traditional methods to monitor and represent small-scale river channel morphology.
  • Landslide induced river bed uplift in the Tal valley of Garhwal Himalaya, India
  • Fluvial processes ; Fluvial terrace ; Garhwal ; India ; Landslide ; Regional geology ; River bed ; Slope ; Slope dynamics ; Vertical movement
  • A large scale landslide occurred in the Tal valley in late January, 1990. This paper discusses the causes and the mechanism of the river bed uplift in relation to the landslide along the river bank.
  • Dimensionless critical shear stress evaluation from flume experiments using different gravel beds
  • Belgium ; Carrying capacity ; Experimentation ; Fluvial processes ; Gravel ; River bed ; Runoff ; Shear stress ; Tracer
  • This paper reports on results from a series of experiments conducted in a flume using four types of bed, differentiated by the size of the bed material. These experiments are intended to complement research undertaken into pebble-bedded rivers