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  • The multivariate controls of hydraulic geometry: a causal investigation in terms of boundary shear distribution
  • Channel geometry ; Discharge ; Fluvial processes ; Multivariate analysis ; River bed ; Roughness ; Stream flow ; United Kingdom ; United States of America
  • Analyse multivariée ; Débit ; Ecoulement fluvial ; Etats-Unis ; Fluviatile ; Géométrie hydraulique ; Lit fluvial ; Royaume-Uni ; Rugosité
  • rivers. 529 observations in the U.K. and the U.S.A. have been analysed. This study also investigates the effects of channel roughness, channel slope and the sediment composition of the channel perimeter on hydraulic geometry.
  • On the basis of experimental results, this paper aims to establish the relationship between a channel shape factor and channel two-dimensional shear stress, and then to investigate the relationship's applicability to both stable canals and natural
  • The relation between channel geometry and suspended sediment transport in the downstream direction
  • Bassin-versant ; Charge en suspension ; Charge solide ; Cours d'eau ; Fluviatile ; Géographie physique ; Géométrie du chenal ; Géométrie hydraulique ; Modèle mathématique
  • A comparison of the data dealing with suspended sediment with the characteristics of the channel geometry parameters suggests the possiblity of constructing a model in which the rate of change in the suspended sediment concentration downstream
  • Controls on channel form and channel change in the Bell River, Eastern Cape, South Africa
  • Cape Province ; Channel geometry ; Fluvial erosion ; Fluvial hydrology ; Meander ; South Africa ; Stream
  • Afrique du Sud ; Cape Province ; Cours d'eau ; Erosion fluviatile ; Géométrie hydraulique ; Hydrologie fluviale ; Méandre
  • Channel instability has occurred in the Bell River in the form of meander cutoffs, incipient meander cutoffs and general channel instability. This is documented for a 40 year period and the causes examined. - (AJC)
  • Catastrophic human-induced change in stream-channel planform and geometry in an agricultural watershed, Illinois, USA
  • Agricultural land use ; Channel geometry ; Drainage network ; Human impact ; Hydraulic works ; Illinois ; Impact ; Rural landscape ; United States of America ; Watershed
  • Action anthropique ; Aménagement hydraulique ; Bassin-versant ; Etats-Unis ; Géométrie hydraulique ; Illinois ; Impact ; Paysage rural ; Réseau de drainage ; Utilisation agricole du sol
  • This study shows that channelization in the Embarras River basin of east central Illinois has altered stream channel and planform geometrie to an extent that exceeds background rates of change for un channelized reaches by one to two orders
  • of magnitude. The average rate of change in channel position resulting from stream responses to channelization also greatly exceeds the average rate of change for unchannelized reaches, yet the spatial extent of stream adjustments to channelization is limited
  • , and most straightened or relocated channels persist in their altered state for decades following channelization.
  • The channel-geometry method: guidelines and applications
  • Channel geometry ; Discharge ; England ; Flood ; Floodplain ; Fluvial hydrology ; Methodology ; River management ; Stream flow ; United Kingdom
  • Aménagement fluvial ; Crue ; Débit ; Ecoulement fluvial ; England ; Géométrie hydraulique ; Hydrologie fluviale ; Méthodologie ; Plaine d'inondation ; Royaume-Uni
  • All river engineering schemes require flood discharge estimates as part of the design and appraisal process. Research on the interrelationship of stream channel geometry and river discharge has provided the basis for an indirect method of flood
  • estimation, the channel-geometry method, which employs river channel dimensions alone to estimate discharge characteristics at ungauged river sites. Channel-geometry equations are developed empirically by relating streamflow data from gauging stations
  • and channel dimensions measured from natural river reaches in the vicinity of the gauge, and take the form of power function relations.
  • Reach-scale channel geometry of a mountain river
  • Channel geometry ; Colorado ; Discharge ; Longitudinal section ; Mountain ; Regression analysis ; Slope gradient ; Stream ; United States of America
  • Analyse de régression ; Colorado ; Cours d'eau ; Débit ; Etats-Unis ; Géométrie hydraulique ; Montagne ; Pente de versant ; Profil longitudinal
  • The AA. used 25 study reaches within the North St Vrain Creek basin to examine control on reach-scale channel geometry. Variables measured included channel geometry, large woody debris, grain size, and mean velocity. Dicussion of the results
  • of linear and multiple regression analyses examining correlations among response and control variables. In general, channel-bed gradient correlates most strongly with variables reflecting channel-boundary resistance or hydraulics, whereas discharge or its
  • surrogate, drainage area, correlates most strongly with channel-form variables.
  • Bed morphology and sedimentology at the confluence of unequal depth channels
  • Canada ; Channel geometry ; Confluent ; Flood ; Fluvial dynamics ; Fluvial processes ; Grain size distribution ; Quebec ; Sediment transport
  • Canada ; Confluence ; Crue ; Dynamique fluviale ; Fluviatile ; Granulométrie ; Géométrie hydraulique ; Québec ; Transport sédimentaire
  • The field study reported here had two objectives: to describe the bed geometry at confluences of unequal depth channels and 2) to examine the relationships between bed morphology, surface sediments properties and flow dynamics as discharge varied
  • Logratio linear modelling of hydraulic geometry using indices of flow resistance as covariates
  • Carrying capacity ; Channel geometry ; Discharge ; Discriminant analysis ; Fluvial hydrology ; Grain size distribution ; Model ; Multivariate analysis ; Statistics
  • Analyse discriminante ; Analyse multivariée ; Capacité de charge ; Débit ; Granulométrie ; Géométrie hydraulique ; Hydrologie fluviale ; Modèle ; Statistique
  • This study develops a statistical model for the relationship between channel friction and at-a-station hydraulic geometry, which presents potential difficulties with regard to both non-linearity and spurious correlation.
  • A model of channel response in disturbed alluvial channels
  • Cours d'eau ; Etats-Unis ; Géographie physique ; Géométrie hydraulique ; Hydrodynamique ; Lit fluvial ; Modèle ; Méandre ; Tennessee
  • The adjustment of channel geometry and phases of channel evolution are characterized by six process-oriented stages of morphologic development : premodified, constructed, degradation, threshold, aggradation, and restabilization. Downcutting and toe
  • removal during the degradation stage causes bank failure by mass wasking when the critical height and angle of the bank material is exceeded (threshold stage). Channel widening continues through the aggradation stage as the slough line develops
  • as an initial site of lower-bank stability. Alternate channel bars form during the restabilization stage and represent incipient meandering of the channel.
  • Hydraulic geometry and maximum flow efficiency as products of the principle of least action
  • Carrying capacity ; Channel geometry ; Concept ; Stream ; Stream flow
  • Capacité de charge ; Concept ; Cours d'eau ; Ecoulement fluvial ; Géométrie hydraulique
  • . The theoretical results obtained here demonstrate that maximum flow efficiency (MFE) determines stable alluvial channel geometry and that this is a product of both maximum sediment transporting capacity (MSTC) and minimum stream power (MSP). Furthermore
  • This study finds that by introducing a channel form factor (width/depth ratio), the self-adjusting mechanism of alluvial channels can be illustrated directly with the basic flow relations of continuity, resistance and sediment transport
  • Comparison of hydraulic geometry between sand- and gravel-bed rivers in relation to channel pattern discrimination
  • Alluvial channel ; Braided channel ; Carrying capacity ; Channel geometry ; Classification ; Data base ; Discharge ; Discriminant analysis ; Gravel ; Meander ; Sand ; Stream ; World
  • Analyse discriminante ; Base de données ; Capacité de charge ; Chenal alluvial ; Chenal anastomosé ; Classification ; Cours d'eau ; Débit ; Gravier ; Géométrie hydraulique ; Monde ; Méandre ; Sable
  • A comparison has been made between the hydraulic geometry of sand- and gravel-bed rivers, based on data from alluvial rivers around the world. The results indicate a significant difference in hydraulic geometry. On this basis, some diagrams
  • for discrimination of meandering and braided channel patterns have been established. To predict the development of channel patterns under different natural conditions, the pattern discriminator should be searched on the basis of independent or at least semi
  • Channel adjustment and a test of rational regime theory in a proglacial braided stream
  • Alberta ; Braided channel ; Canada ; Channel geometry ; Discharge ; Grain size distribution ; Gravel ; Proglacial lake ; Sediment load ; Stream
  • Alberta ; Canada ; Charge solide ; Chenal anastomosé ; Cours d'eau ; Débit ; Granulométrie ; Gravier ; Géométrie hydraulique ; Lac proglaciaire
  • The AA. analyze the historical trends in channel pattern and the contemporary downstream changes in channel geometry, grain size, and gradient in the gravel bed, proglacial Sunwapta River, Alberta. The rational equations incorporate the effect
  • of grain size and slope on channel width and the effect of width and grain size on channel slope. The regime equations are successful even though they were devised for single channel gravel streams. The results confirm the influence of grain size on channel
  • pattern thresholds and demonstrates, using spatial transitions in channel pattern, that channel pattern predictions based on stream power alone are inadequate.
  • Types of river channel patterns and their natural controls
  • Braided channel ; Channel geometry ; Classification ; Discharge ; Floodplain ; Hydrological regime ; Meander ; Stream ; Terminology
  • Chenal anastomosé ; Classification ; Cours d'eau ; Débit ; Géométrie hydraulique ; Méandre ; Plaine d'inondation ; Régime hydrologique ; Terminologie
  • River channel patterns are thought to form a morphological continuum. This continuum is two-dimensional, defined by plan features of which there are three (straight, meandering, branching), and structural levels of fluvial relief of which
  • there are also three (floodplain, flood channel, low-water channel). Combinations of these three categories define the diversity of patterns. The critical stream power values and hydrological regime together define the channel pattern, and analysis of the pattern
  • The influence of bank strength on channel geometry : an integrated analysis of some observations
  • Bank erosion ; Channel geometry ; Discharge ; Gravel ; Model ; Multivariate analysis ; Riparian vegetation ; River bed ; Sedimentology ; Stream ; Vegetation
  • Analyse multivariée ; Cours d'eau ; Débit ; Erosion des berges ; Gravier ; Géométrie hydraulique ; Lit fluvial ; Modèle ; Sédimentologie ; Végétation ; Végétation ripicole
  • Bank strength exerts a significant influence on river channel geometry. In order to undertake an integrated analysis of wide-ranging field observations, this study applies a recently developed multivariate model of channel geometry. When the banks
  • in channel width and a two-fold change in depth corresponding to about a 1.6-fold change in cross-sectional area.
  • Semi-determinate hydraulic geometry of river channels, South Island, New Zealand
  • Analyse des données ; Cours d'eau ; Géographie de l'Océanie ; Géométrie hydraulique ; Lit fluvial ; Nouvelle-Zélande ; Réseau de drainage ; South Island
  • Analyses de données sédimentologiques, hydrologiques et morphologiques de 72 cours d'eau ayant pour but de déterminer leur part dans la géométrie hydraulique des cours d'eau.
  • Anastomosis and the continuum of channel pattern
  • Australia ; Canada ; Channel geometry ; Classification ; Concept ; Flood ; Floodplain ; Fluvial processes ; Meander ; River bed
  • Australie ; Canada ; Classification ; Concept ; Crue ; Fluviatile ; Géométrie hydraulique ; Lit fluvial ; Méandre ; Plaine d'inondation
  • Anastomosing rivers are characterized by multiple channels separated by islands excised from the floodplain. Their status relative to the continuum concept of channel pattern is assessed with channel pattern defined in terms of three variables: flow
  • strentgh, bank erodibility and relative sediment supply. Anastomosis may in certain cases represent a transitional form of channel pattern but there is no denying the longevity of some anastomosing systems.
  • Channel characteristics and formation mechanism of Ganjiang River
  • Bank erosion ; Braided channel ; Channel geometry ; China ; Discharge ; Grain size distribution ; Jiangxi ; Seasonal variability ; Sediment load ; Stream
  • Charge solide ; Chenal anastomosé ; Chine ; Cours d'eau ; Débit ; Erosion des berges ; Granulométrie ; Géométrie hydraulique ; Jiangxi ; Variabilité saisonnière
  • Relative straight channel of the middle and upper reaches of Ganjiang has been formed due to the contraction of mountains and hills being composed of bedrocks on both banks of the river. But however, at the lower reaches, branching channel
  • predominates due to limited contracting force of the river banks as the evolution and development of branching channels are closely related with locations and controle effect of nodal points. There are sufficient water containing less sediments in particles
  • Pool and riffle characteristics in relation to channel gradient
  • California ; Channel geometry ; Fluvial processes ; Geomorphometry ; Longitudinal section ; United States
  • California ; Etats-Unis ; Fluviatile ; Géomorphométrie ; Géométrie hydraulique ; Profil longitudinal
  • The channel gradients, along three rivers in coastal northern California, discussed in this paper are higher than those often reported for channels with pool-riffle, rather sequences. However, the AA. have designated these as pool-riffle, than step
  • -pool, channels, because of the presence of a strong lateral flow component, and the lack of well-organized bed-steps spanning the entire channel width.
  • Channel-unit hydraulics on a pool-riffle channel
  • Channel geometry ; Colorado ; Longitudinal section ; Roughness ; Stream ; Stream flow ; United States of America
  • Colorado ; Cours d'eau ; Ecoulement fluvial ; Etats-Unis ; Fosse-seuil ; Géométrie hydraulique ; Profil longitudinal ; Rugosité
  • in this fixed boundary channel with laterally constricted pools, and to explore potential controls on observed patterns of velocity and water surface gradient among channel units.
  • Channel instability in a forested catchment : a case study from Jones Creek, East Gippsland, Australia
  • Australia ; Channel geometry ; Flood ; Forest ; Riparian vegetation ; River bed ; Victoria ; Watershed
  • Australie ; Bassin-versant ; Crue ; Forêt ; Géométrie hydraulique ; Lit fluvial ; Victoria ; Végétation ripicole
  • Jones Creek, a forested sub-catchment of the Genoa River, Victoria, southeastern Australia, has experienced channel metamorphosis induced by a series of floods since 1971. The role of within-channel vegetation, large woody debris and sediment
  • retention are examined as integral components for the onset of channel recovery, thereby adding to the theoretical notions on channel behaviour following incision.