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  • Which tributaries disrupt downstream fining along gravel-bed rivers?
  • British Columbia ; Canada ; Carrying capacity ; Classification ; Discriminant analysis ; Grain size distribution ; Gravel ; River bed ; Sedimentology ; Stream ; Watershed
  • In this paper a procedure for identifying significant lateral (tributary) sources, whithout the benefit of grain-size information, is outlined. A high-resolution characterisation of bed material texture along 2 Canadian gravel-bed rivers facilated
  • The reconstruction of bed material yield and supply histories in gravel-bed streams
  • Carrying capacity ; Gravel ; Meltwater ; Mountain ; Numerical model ; Pic discharge ; River bed ; Sediment budget ; Sediment load ; Sediment transport ; Stream ; Switzerland ; Valais ; Watershed
  • This paper details a basic method for estimation of both bed material yield and supply rates for a glaciated catchment. A simple regression relationship between discharge and erosion volume was used to predict the work done by the channel
  • in the absence of bed material supply from upstream. The bed material that must have been supplied from upstream between any 2 monitoring periods could then be determined by calculating the amont of sediment that had to be supplied to the reach between DTM
  • Muddy waters: uncertainty issues in modelling the influence of bed sediments on water composition
  • Model ; Netherlands (The) ; Poland ; River bed ; Sediment load ; Stream ; Suspended load ; Water quality ; Watershed
  • The primary aim of this study has been to quantify the role of bed sediments for the water composition or water quality at the catchment scale of small flowing surface waters by means of spatial and dynamic modelling. The research areas were
  • the Biebrza River in Poland and the Langbroekerwetering in the Netherlands. - (AGD)
  • Coarse bed load transport in an alluvial gravel bed stream, Dupuyer Creek, Montana
  • Alluvial channel ; Montana ; River bed ; Sampling ; Sediment load ; Sediment transfer ; Stream ; United States of America
  • Woody vegetation and channel morphogenesis in low-gradient, gravel-bed streams in the Ozark Plateaus, Missouri and Arkansas
  • Arkansas ; Carrying capacity ; Channel geometry ; Flood ; Floodplain ; Fluvial processes ; Missouri ; River bed ; Tree ; United States of America ; Vegetation
  • This paper presents the results of a study of relations between woody vegetation and channel morphogenesis in gravel-bed streams of the Ozark Plateaus. These results have implications for general models of channel morphogenesis in gravel-bed streams
  • Anabranched rivers
  • Channel geometry ; China ; Fluvial dynamics ; Fluvial processes ; Meander ; Model ; River bed ; Statistics ; Stream ; Stream flow
  • Since the anabranched river pattern is the most typical one in the middle and lower reaches of the Yangtze River (Changjiang) as well as in many other rivers in China, a systematic study on the formation cause of the anabranched river pattern has
  • been made in recent years, including field observations, modeling experiments in four river models under different boundary conditions, the analyses of river pattern formation and transformation etc. In this paper, some of the detailed results obtained
  • Flow modelling in gravel-bed rivers: rethinking the bottom boundary condition
  • England ; Grain size distribution ; Gravel ; Model ; River bed ; Roughness ; Simulation ; Stream ; Stream flow ; United Kingdom
  • A key problem in computational fluid dynamics (CFD) modelling of gravel-bed rivers is the representation of multi-scale roughness, which spans the range from grain size, through bedforms, to channel topography. These different elements of roughness
  • -resolution topography. The results show the ability of the model to capture the spatially-averaged flow field and, thus, illustrate its potential for representing flow processes in natural gravel-bed rivers. Finally, practical data requirements
  • do not clearly map onto a model mesh and use of simple grain-scale roughness parameters may create numerical problems. This paper presents CFD simulations for 3 cases: a plane bed of fine gravel, a plane bed of fine gravel including large, widely
  • -spaced pebble clusters, and a plane gravel bed with smaller, more frequent, protruding elements. Here, the spatially-averaged velocity and eddy viscosity are used to investigate the applicability of the model, compared with using the explicit high
  • Active width of gravel-bed braided rivers
  • The AA. compare theoretical predictions of active width in gravel-bed braided rivers with observations from Sunwapta River, (Alberta, Canada), and from a generic physical model of gravel braided rivers, to describe and measure trends and variability
  • in active width. From these empirical results, the AA. formulate a general relation that predicts active width over a range of braided river types and flow conditions. This paper also raises questions about differences between hydraulically-based numerical
  • model computations of instantaneous active width and observation of time-integrated morphological active width. Understanding these differences can give insight into the nature of bedload transport in braided rivers and the relationship to morphological
  • Visualization of the turbulent flow structure in a gravel-bed river
  • A novel technique for visualizing turbulent flow data from a gravel-bed river is presented. The time development of flow velocity and shear stress at three heights is displayed using a computer program. This can be used to observe how
  • Channel bed adjustment along mine-affected rivers of northeast Tasmania
  • This paper analyses channel response to a sediment supply which was particularly variable in time and space, focusing on the scale and rate of bed height adjustment. It exemplifies the kind of transient behaviour experienced by river systems whose
  • Hyporheic flow as a potential geomorphic agent in the evolution of channel morphology in a gravel-bed river
  • ) and channel erosion (bank erosion) appeared to contribute to the formation of the head-cut gullies. Hyporheic flow is an important component in the geomorphic evolution of channels and the floodplain in a gravel-bed river.
  • Estimating critical stream power for bedload transport calculations in gravel-bed rivers
  • Carrying capacity ; Fluvial dynamics ; Gravel ; Hydrodynamics ; River bed ; Sediment load ; Stream ; Threshold
  • Analysis of bedload transport characteristics of Idaho streams and rivers
  • are used to identify different influences on bedload transport rates in analyzed gravel-bed rivers.
  • 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
  • A study of river channel pattern information recorded by grain size parameters of fluvial sediment
  • Using data from some Chinese rivers, an attempt has been made to express quantitavely, by using statistical methods, the connections between river channel pattern characteristics and the corresponding river bed material grain size parameters.
  • Minimum Froude number and the equilibrium of alluvial sand rivers
  • Computer simulations for sand bed rivers show that the Froude number of the flow tends to a minimum value when the equilibrium river tends to a certain hydraulic geometry. Evidence from 57 alluvial sand material rivers and stable canals shows
  • Channel sediment variability along a river : a case study of the Siret River (Romania)
  • of the pebbles, relating these to the river bed and floodplain geometry and to some properties of the drainage basin.
  • Computational fluid dynamics modelling of boundary roughness in gravel-bed rivers : an investigation of the effects of random variability in bed elevation
  • over 2 contrasting gravel beds. The aims of this study are : to assess the performance of the CFD model; to identify the limitations of the conventional wall function approach; to explore the potential for modelling intermediate-scale roughness effects
  • using a random elevation model, and to address the wider implications of these results for the application of CFD models to natural gravel-bed channels.
  • Short and long-term changes to bed mobility and bed composition under altered sediment regimes
  • Channel geometry ; Dam ; Ecosystem ; Grain size distribution ; Hydraulic works ; Model ; River regime ; Sediment transport ; Stream ; United States of America
  • Using long-term discharge and cross-sectional data in combination with a two-fraction sediment transport model, the AA. assess changes in the downstream bed of 2 flow-regulated rivers with equivalent dam-induced changes in flow but opposite changes
  • in sediment flux. Supply limitation has led to incision and armoring in one case while supply excess has led to aggradation and embeddedness in the other. The results demonstrate the importance of considering bed composition on sediment transport predictions
  • Channel form, bed material and sediment sources of the Sprongdøla, southern Norway : evidence for a distinct periglaciofluvial system
  • Avalanche ; Carrying capacity ; Fluvial processes ; Freeze-thaw cycle ; Grain size distribution ; Mountain ; Norway ; Periglacial features ; River bed
  • in the shape and size of channel bed material. Comparisons are made with the channel form, bed material characteristics and associated sediment sources in temperate river environments. This leads on to an evaluation of the concept of a process-sediment-landform
  • This paper is a geomorphological and sedimentological case study of a typical periglacial river in the alpine and subalpine zone of southern Norway. It focuses on the nature and effects of the sediment sources that contribute to downstream variation
  • Process-form interactions in unstable sand-bed river channels : a numerical modeling approach
  • Bank erosion ; Carrying capacity ; Channel geometry ; Model ; Numerical model ; River bed ; Shear stress ; Stream ; Stream flow
  • A deterministic numerical model of bed deformation and channel widening, which accounts for specific mechanisms of bank erosion and collapse, is used to analyze morphological and flow-energy parameters in adjusting sand-bed channels, for a range