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  • Estimation of flow resistance in gravel-bedded rivers : a physical explanation of the multiplier of roughness length
  • Fluvial processes ; Grain size distribution;Granulometry ; Gravel ; Hydrodynamics ; River bed ; Roughness ; Sand ; Sediment load ; Turbulence
  • In this paper, two contrasting approaches are used to suggest that the multiplier of characteristic grain size is attribuable to the effect of small-scale form resistance, reflecting the occurrence of microtopographic bedforms in gravel-bedded
  • environments. Apart from improving the capacity to determine friction factors for velocity and discharge estimation, the findings have implications in general for the initial motion of gravelly bed material.
  • Quantitative determination of the activity of within-reach sediment storage in a small gravel-bed river using transit time and response time
  • Carrying capacity ; Channel geometry ; Grain size distribution ; Gravel ; Methodology ; Quantitative analysis ; River bed ; Scotland ; Sediment load ; Storage site ; Stream ; Tracer ; United Kingdom
  • This paper demonstrates how fractional sediment storage activity in a gravel-bed river can be quantified using a within-reach sediment budget and reservoir theory. Deployment of magnetic tracer particles allows accurate characterisation of sediment
  • fluxes in gravel-bed rivers and provide the opportunity to quantify storage activity using reservoir theory. The results suggest that transit time is difficult to determine from tracer studies in gravel-bed rivers. Consequently, a refinement of transit
  • Chaos and order. The channel geometry of gravel bed braided rivers in Geomorphological models. Theoretical and empirical aspects.
  • During their studies in Butramo basin, Calabria, the AA. became convinced that the braided rivers are not at all chaotic, but are extremely well regulated fluvial systems with an optimum efficiency in carrying both water and bed load.
  • Flow and particle paths at a natural river confluence with coarse bed material
  • This paper reports on an experiment conducted at a natural channel confluence (Ruisseau du Sud and Eaton North River) with coarse bed material. The main objective of the experiment was to describe flow and sediment transport patterns.
  • Bedload transport processes in a braided gravel bed river model
  • A 1:50 scale hydraulic model was designed, based on Froude number similarity and using hydrological and sediment data from a small braided gravel-bed river (the North Branch of the Ashburton River, Canterbury, New Zealand). The qualitative results
  • of the experiments using steady flows and unsteady flows reveal the nature of bedload transport (BLT) processes in braided rivers, particularly regarding variability of BLT in braided rivers.
  • Bed-material transport estimated from channel surveys: Vedder River, British Columbia
  • This study investigates the possibility to estimate bed-material bed-material transport by analysis of morphological changes along a river channel, by assessment of erosion and deposition in Vedder River, British Columbia.
  • On large-scale flow structures in a gravel-bed river
  • Canada ; Carrying capacity ; Experimentation ; Gravel ; Quebec ; River bed ; Runoff ; Stream ; Stream flow ; Turbulence
  • This paper confirms the presence of large-scale flow structures in gravel bed rivers, pictures their sequence and patterns and characterises their mean and individual properties. The analysis relies on a new technique for displaying velocity
  • The dominance of dispersion in the evolution of bed material waves in gravel-bed rivers
  • This paper summarizes recent theoretical models, experiments and field studies that have been designed specifically to measure relative rates of dispersion and translation of bed material waves. In considering uniform channels only, and also
  • in disregarding exchanges of sediment between a channel and its floodplain, 2 factors influence wave behaviour : interactions between flow, wave topography and bed load transport; and relative particle sizes of input sediment and pre-existing bed material
  • . The results indicate that dispersion dominates the evolution of bed material waves in gravel-bed channels.
  • The river-bed : a dynamic store for plant propagules ?
  • Wood in world rivers. Special issue
  • This paper investigates temporal variations in the abundance, species composition and richness, and spatial distribution of plant propagules stored on river-beds. Samples of the surface layers of river-bed sediments were obtained from 2 reaches
  • of the River Frome, Dorset, and one reach of the River Tern, Shropshire. Propagules were preferentially stored within particular bed habitats. The preferential accumulation of sediment and species-rich propagules around stands of marginal emergent vegetation
  • Channel adjustments, bedload transport and sediment sources in a gravel-bed river, Brenta River, Italy
  • Multi-scale characterization and evolution of channel forms in gravel-bed rivers
  • This paper deals with the Brenta River, a gravel-bed river strongly affected by human impact. The aims of this work are 1) to reconstruct the channel adjustments that have occurred during the last decades and 2) to analyse the present condition
  • of the river in terms of bedload transport and sediment sources. The study reach was investigated using historical maps, aerial photographs, monumented cross-sections, laser altimetry data and field survey. Bedload transport rates were estimated
  • by a morphological approach, which allows the construction of a sediment budget. The results should be taken into account in addressing sediment management and restoration along a dynamic and unstable river such as the Brenta.
  • Visual characterization technique for gravel-cobble river bed surface sediments; validation and environmental applications contribution to the programme of CIRSA (Centre Interuniversitaire de Recherche sur le Saumon Atlantique)
  • Canada ; Ecosystem ; Fish ; Fluvial processes ; Grain size distribution ; Gravel ; Habitat ; Quebec ; Research technique ; River bed ; Sampling ; Stream
  • This study proposes a useful alternative visual technique to characterize the surface substrate (size and distribution) over an expanse of a gravel-bed river. The paper is divided into 4 sections : a brief review of bed sediment sampling techniques
  • ; an explanation of the methodology and training protocol used for the visual estimation of a river bed surface sediment size distribution; the error estimation linked to this technique and a comparison with common surface sampling techniques (grid sampling
  • Temporal and spatial variability in thalweg profiles of a gravel-bed river
  • Special issue : Changing times-Changing rivers
  • California ; Channel geometry ; Flood ; Gravel ; Longitudinal section ; River bed ; Sediment load ; Spatial variation ; Stream ; United States of America
  • This study used successive longitudinal thalweg profiles in gravel-bed rivers to monitor changes in bed topography following floods and associated large sediment inputs. Variations in channel bed elevations, distributions of residual water depths
  • Discharge ; European part of USSR ; Flow ; Fluvial dynamics ; Fluvial processes ; Former USSR ; Region ; River bed ; Stream
  • Based on the calculations of river bed-forming water discharges on rivers (according to N. I. Makkaveyev's method) there is proved the scheme of regionalization of European territory of the Union according to the conditions of their distribution
  • . There are distinguished five sub-latitudinal zones and one meridional (the Urals) belt which differ according to the presence or the absence of the upper-range of the river bed-forming discharge which corresponds to the submerged flood-plain. For each region and district
  • is given the description of the river bed and its deformations which are correlated with the river bed-forming water discharges.―(L'A.).
  • Evorzni jevy recistich krkonossko-jizerského krystalinika Evorsional phenomena in the river beds of the Krkonose-Jizerské hory Mountains crystalline complex
  • The existence of evorsion phenomena of river beds on the rivers and currents of Giant and Jizerské hory Mountains crystalline complex proves that the strike of schistosity at the dominant joints and the course of river stream give the most
  • Bankfull discharge recurrence interval in gravel-bed rivers
  • Bankfull discharge was identified in some 30 gravel-bed rivers representing in total c. 40 gauging stations. The catchment sizes vary from 4km2 to nearly 2700 km2. Bankfull discharge value increases with basin size. The selected rivers are spread
  • over 5 natural regions which show strong lithological differences. The AA. study the bankfull discharge recurrence interval for rivers flowing on permeable and impermeable terrain.
  • Downstream variation in grain size along an Alpine river : analysis of controls and processes
  • Braided channel ; Grain size distribution ; Gravel ; Human impact ; Hydraulic works ; Italy ; River bed ; Sediment load ; Stream ; Trentino-Alto Adige
  • This study concerns downstream variation in bed material size along a 115-km reach of the Piave River in north-eastern Italy. This river drains a region producing high sediment yields (the Dolomites and the Prealps) and has a braided pattern along
  • half of its length. The A. analyses the changes of bed material size in the downstream direction and explains these changes in the light of both natural and anthropogenic factors.
  • Stability, morphology and surface grain size patterns of channel bifurcation in gravel-cobble bedded anabranching rivers
  • This study presents a detailed field study of the morphology and bed sediment patterns of 5 channel bifurcations on the Renous River, New Brunswick, and a regional description of bifurcation angles within anabranching rivers in the Miramichi Basin
  • , New Brunswick. The stability of channels upstream of bifurcations and the location of bars at bifurcations influence bifurcation stability and the maintenance of river anabranching in the long term.
  • Differential bed sedimentology and the maintenance of riffle-pool sequences
  • Carrying capacity ; Devon ; England ; Fluvial processes ; Model ; River bed ; Sedimentology ; Statistics ; United Kingdom
  • field. High-frequency velocity measurements obtained using an array of electromagnetic current meters are combined with results from grid and transect sampling of bed sediments from 9 sites on 3 small upland rivers in N. Exmoor, U.K.
  • The purpose of this paper is to clarify several aspects of the sedimentology of riffle-pool sequences, and to suggest how these both reflect and control riffle-pool stability in the presence of spatial differences in the turbulent near-bed flow
  • A new sampler for extracting bed material sediment from sand and gravel beds in navigable rivers
  • In order to collect grain-size distributions of sand and gravel bed sediments in navigable rivers, the A. developed a variant of the drag bucket sampler that improves bed penetration and increases sampler aperture to extend its applicability
  • to gravel beds. Discussion of the results.
  • Water-worked gravel beds in laboratory flumes - a natural analogue ?
  • Carrying capacity ; Digital elevation model ; England ; Experimentation ; Fluvial dynamics ; Grain size distribution ; Gravel ; River bed ; Stream ; Stream flow ; Topography ; United Kingdom
  • beds offers an improved way of investigating intragravel flow and sediment-water interface exchange processes in gravel-bed rivers at a laboratory scale.
  • Two types of bed formation were examined : one where sediment is manually placed and screeded and the second where sediment is fed into a running flume. This later technique created deposits through sequential cycles of sediment transport
  • and deposition. Detailed bed surface topography measurements have been made over a screeded bed and three fed beds. In addition, bulk subsurface porosity and hydraulic conductivity have been measured. By comparing the four beds, results revealed that certain
  • physical properties of the screeded bed were clearly different from those of the fed beds. This study clearly showed that caution should be taken when comparing velocity measurements over screeded beds with water-worked beds, and that the formation of fed