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Estimating solute transport in streams from grab samples

Estimating solute transport in streams from grab samples

The geomorphic significance of log steps in forest streams

The geomorphic significance of log steps in forest streams
Coast Ranges ; Cours d'eau ; Etats-Unis ; Forêt ; Géographie de l'Amérique ; Montagne ; Oregon ; Transport solide ; Transport sédimentaire ; Tronc d'arbre

Feedbacks between erosion and sediment transport in experimental bedrock channels

Feedbacks between erosion and sediment transport in experimental bedrock channels
Experimentation ; Fluvial erosion ; Roughness ; Sediment transport ; Stream ; Stream flow ; Topography ; Turbulence ; United States of America ; Utah
Cours d'eau ; Ecoulement fluvial ; Erosion fluviatile ; Etats-Unis ; Expérimentation ; Rugosité ; Topographie ; Transport sédimentaire ; Turbulence ; Utah
transported as bedload, a single erosion mechanism (abrasion) and sediment-starved transport conditions. They find that patterns of erosion both create and are sensitive functions of the evolving bed topography because of feedbacks between the turbulent flow
field, sediment transport and bottom roughness.

Vegetation growth in rivers : influences upon sediment and nutrient dynamics

Biomass ; Ecosystem ; Fluvial dynamics ; Geochemistry ; Nutrient ; Sediment transport ; Stream ; Vegetation
Biomasse ; Cours d'eau ; Dynamique fluviale ; Ecosystème ; Géochimie ; Macrophyte ; Nutriment ; Transport sédimentaire ; Végétation
This paper presents a review of research on macrophyte-mediated processes within streams and calls for a greater appreciation of these processes in future hydro-geomorphological research in streams with abundant vegetation. The influence

Coarse sediment transport in mountain streams in Colorado and Wyoming, USA

Coarse sediment transport in mountain streams in Colorado and Wyoming, USA
Carrying capacity ; Colorado ; Fluvial dynamics ; Grain size distribution ; Mountain ; River bed ; Sediment load ; Stream ; Stream flow ; Typology ; United States of America ; Wyoming
The AA. use data from 19 sites to characterize patterns and rates of coarse sediment transport for a range of channel types and sizes, including step-pool, plane-bed, pool-riffle, and near-braided channels. This effort builds upon previous work
where the AA. applied a piecewise regression model to relate flow to rates of bedload transport and to define phases of transport in coarse-grained channels. While there were many similarities in observed patterns of bedload transport at the 19 studied
sites, each had its own bedload signal in that the rate and size of materials transported largely reflected the nature of flow and sediment particular to that system.

A stability criterion inherent in laws governing alluvial channel flow

Carrying capacity ; Channel geometry ; Mathematical hydrology ; Runoff ; Sediment transport ; Stream ; Stream flow
Capacité de charge ; Cours d'eau ; Ecoulement ; Ecoulement fluvial ; Géométrie hydraulique ; Hydrologie mathématique ; Transport sédimentaire
and bedload transport formulae. This study provides support for the use of the criteria of MFE, maximum sediment transporting capacity and minimum stream power for understanding the operation of alluvial rivers, and also addresses limitations to the direct

Tributary-trunk stream relations in a cut-and-fill landscape : a case study from Wolumla catchment, new South Wales, Australia

Tributary-trunk stream relations in a cut-and-fill landscape : a case study from Wolumla catchment, new South Wales, Australia
Australia ; Ecosystem ; Fluvial erosion ; Human impact ; Hydrological regime ; New South Wales ; Sediment transport ; Stream ; Watershed
Action anthropique ; Affluent ; Australie ; Bassin-versant ; Cours d'eau ; Ecosystème ; Erosion fluviatile ; New South Wales ; Régime hydrologique ; Transport sédimentaire
In this paper, the timing of incision and the relation between trunk stream and tributary streams are explained for Wolumla catchment on the south coast of New South Wales. To date, the linkage of tributary and trunk streams has been neglected
in studies of cut-and-fill landscapes, yet this has significant impacts on the within-catchment transfer of water and sediment. This study also records how human impacts on the character and behaviour of the trunk stream may have profound secondary impacts

Effects of woody debris on channel morphology and sediment storage in headwater streams in the Great Smoky Mountains, Tennessee-North Carolina

Effects of woody debris on channel morphology and sediment storage in headwater streams in the Great Smoky Mountains, Tennessee-North Carolina
Bank erosion ; Channel geometry ; Dendrochronology ; Fluvial dynamics ; Forest ; Mountain ; North Carolina ; Sediment transport ; Stream ; Tennessee ; United States of America
Cours d'eau ; Dendrochronologie ; Dynamique fluviale ; Débris ligneux ; Erosion des berges ; Etats-Unis ; Forêt ; Géométrie hydraulique ; Montagne ; North Carolina ; Temps de résidence ; Tennessee ; Transport sédimentaire
This study invesigates the effect of coarse woody debris, CWD, on bankfull channel dimensions and in-channel sediment storage along second-order streams. Comparisons are made between streams that have experienced recent debris slides and those
that have not. CWD channel obstructions are larger but less frequent along debris-slide-affected streams. Dendrochronological evidence indicates that CWD can remain in channels for over 100 yr. CWD causes channel widening along all study streams

Estimation of bedload transport in headwater streams using a numerical model (Moravskoslezké Beskydy Mts, Czech Republic)

Estimation of bedload transport in headwater streams using a numerical model (Moravskoslezké Beskydy Mts, Czech Republic)
Applied hydrology ; Czech Republic ; Flood ; Headwater ; Moravian-Silesian Beskids mountain ; Numerical model ; Sediment load ; Sediment transport ; Stream
Charge solide ; Cours d'eau ; Cours supérieur ; Crue ; Hydrologie appliquée ; Modèle numérique ; Moravskoslezské Beskydy ; Tchèque république ; Transport sédimentaire
Carga solida ; Corriente de agua ; Crecida ; Hidrología aplicada ; Modelo numérico ; República Checa ; Transporte sedimentario
The TOMSED numerical model was successfully applied on the May 2010 flood event in headwater streams of the Czech part of the Western Flysch Carpathians. The Manning equation was used together with application of a reduced energy gradient
lower flow resistance resulting in a higher intensity of bedload transport. - (EN)

Bed material transport estimated from the virtual velocity of sediment

Bed material transport estimated from the virtual velocity of sediment
British Columbia ; Canada ; Carrying capacity ; Flood ; Gravel ; Island ; Methodology ; Porosity ; River bed ; Sediment transport ; Stream ; Stream flow ; Tracer ; Vancouver
British Columbia ; Canada ; Capacité de charge ; Cours d'eau ; Crue ; Ecoulement fluvial ; Gravier ; Ile ; Lit fluvial ; Méthodologie ; Porosité ; Traceur ; Transport sédimentaire ; Vancouver
This study evaluates the possibility of determining bed material transport using the virtual rate of travel of individual particles, dimensions of the active layer of the streambed, and porosity and density of streambed material. Magnetically tagged
stones and scour indicators were employed in Carnation Creek, British Columbia, to quantify transport rates.

Entrainment, displacement and transport of tracer gravels

Entrainment, displacement and transport of tracer gravels
California ; Carrying capacity ; Experimentation ; Grain size distribution ; Methodology ; Sediment transport ; Stream ; Stream flow ; Tracer ; United States of America
California ; Capacité de charge ; Cours d'eau ; Ecoulement fluvial ; Etats-Unis ; Expérimentation ; Granulométrie ; Méthodologie ; Traceur ; Transport sédimentaire
This paper addresses several aspects of the collection, analysis and interpretation of tracer gravel observations, with the general objectives of increasing the information yield of a tracer gravel programme and improving the accuracy of transport
estimates from tracer gravels. The expected variation with grain size of tracer displacement length is developed and illustrated using displacement lengths calculated from measurements of entrainment, surface size distribution and transport rate

Dnový transport sedimentů v souvisloti s transformací geomorfologického režimu štěrkonosných toků Moravskoslezských Beskyd

Dnový transport sedimentů v souvisloti s transformací geomorfologického režimu štěrkonosných toků Moravskoslezských Beskyd
Transport de la charge solide en relation avec la transition géomorphologique des lits des cours d'eau à graviers dans les montagnes de Moravskoslezské Beskydy
Channel geometry ; Czech Republic ; Discharge ; Gravel ; Moravian-Silesian Beskids mountain ; River bed ; Sediment load ; Sediment transport ; Stream
Charge solide ; Cours d'eau ; Débit ; Gravier ; Géométrie hydraulique ; Lit fluvial ; Moravskoslezské Beskydy ; Tchèque république ; Transport sédimentaire
Carga solida ; Cauce ; Caudal ; Corriente de agua ; Geometria hidráulica ; Grava ; República Checa ; Transporte sedimentario
This paper summarizes the results of bedload transport research in the Morávka, Mohelnice and Ostravice basins, conducted using the BAGS (Bedload Assessment for Gravel-bed Streams) spreadsheet-based program and unit stream power empirical formulas
. The presented results only show the potential rate of bedload transport, because sediment inputs and barriers were not included into the model. The results may be applied to improve local watershed management. - (EN)

Adjustment of stream-channel shape to hydrologic regime

Adjustment of stream-channel shape to hydrologic regime
Charge de fond ; Débit ; Ecoulement ; Fluviatile ; Forme ; Géographie physique ; Hydrodynamique ; Lit fluvial ; Transport solide
On connait déjà la tendance qu'ont les chenaux à s'adapter au transport de fond de lit. L'A. montre comment la forme des chenaux devient optimale pour le débit qui assure le transport de la charge solide de fond la plus importante.

Longitudinal changes in the size and shape of stream bed material: evidence of variable transport conditions

Longitudinal changes in the size and shape of stream bed material: evidence of variable transport conditions
La modification des caractéristiques granulométriques et morphoscopiques vers l'aval est utilisée pour identifier les conditions dominantes de transport dans un bassin dont les deux principales lithologies ont une distribution spatiale différente.

Characteristics, distribution and geomorphic role of large woody debris in a mountain stream of the Chilean Andes

Characteristics, distribution and geomorphic role of large woody debris in a mountain stream of the Chilean Andes
Andes ; Channel geometry ; Chile ; Impact ; Longitudinal section ; Mountain ; Sediment budget ; Sediment transport ; Stream
Andes ; Bilan sédimentaire ; Bois flottant ; Chili ; Cours d'eau ; Géométrie hydraulique ; Impact ; Montagne ; Profil longitudinal ; Transport sédimentaire
This paper presents an analysis of amounts, characteristics and morphological impact of large woody debris (LWD) in the Tres Arroyos stream, draining an old-growth forested basin of the Chilean Southern Andes. The AA. compare the results

Residence times of alluvium in an east Texas stream as indicated by sediment color

Residence times of alluvium in an east Texas stream as indicated by sediment color
Alluvium ; Geochemistry ; Indicator ; Sediment transport ; Sedimentology ; Stream ; Texas ; United States of America
Alluvion ; Couleur ; Cours d'eau ; Etats-Unis ; Géochimie ; Indicateur ; Oxyde de fer ; Sédimentologie ; Temps de résidence ; Texas ; Transport sédimentaire
The systematic changes in iron geochemistry often experienced by sediments deposited in an anaerobic environment, such as stream channel or waterlogged floodplain, are used here as an indicator of residence time over contemporary time scales

Estimating critical stream power for bedload transport calculations in gravel-bed rivers

Estimating critical stream power for bedload transport calculations in gravel-bed rivers
Carrying capacity ; Fluvial dynamics ; Gravel ; Hydrodynamics ; River bed ; Sediment load ; Stream ; Threshold
The physical basis of Bagnold's equation for critical stream power is examined. More general equations are presented which overcome the limitations of this equation. They require a knowledge of channel slope, but not depth. The analysis suggests

Testing bedload transport formulae using morphologic transport estimates and field data : lower Fraser River, British Columbia

Testing bedload transport formulae using morphologic transport estimates and field data : lower Fraser River, British Columbia
British Columbia ; Canada ; Carrying capacity ; Channel geometry ; Forecast ; Grain size distribution ; Mathematical model ; Research technique ; Sediment transport ; Stream
British Columbia ; Canada ; Capacité de charge ; Cours d'eau ; Fraser River ; Granulométrie ; Géométrie hydraulique ; Modèle mathématique ; Prévision ; Technique de recherche ; Transport sédimentaire
Morphologic transport estimates available for a 65-km stretch of Fraser River over the period 1952-1999 provide a unique opportunity to evaluate the performance of bedload transport formulae for a large river over decadal time scales. Formulae
tested in this paper include the original and rational versions of the Bagnold formula, the Meyer-Peter and Muller formula and a stream power correlation. The formulae differ in their sensitivity to input variables and between reaches. Average annual
bedload transport predictions for the 4 formulae show that they vary between each other as well as from the morphologic transport estimates.

A unit stream power based sediment transport function for overland flow

A unit stream power based sediment transport function for overland flow
Analyse statistique ; Bassin-versant ; Concept ; Ecoulement superficiel ; Erosion des sols ; Erosion hydrique ; Modèle ; Transport sédimentaire
Concept ; Model ; Overland flow ; Sediment transport ; Soil erosion ; Statistical analysis ; Water erosion ; Watershed
Análisis estadístico ; Concepto ; Cuenca hidrográfica ; Erosión de los suelos ; Erosión hídrica ; Escorrentíasuperficial ; Modelo ; Transporte sedimentario
and sediment conditions for which each was formulated. To improve predictions of transport capacity under overland flow conditions, especially at low flow intensities, a new function, based on the unit stream power concept, was derived using experimental data.
The suitability of 5 sediment transport capacity functions was evaluated for overland flow conditions using graphical and statistical analysis. The results show that the application of these functions is limited to the range of hydraulic

Effects on bedload transport of experimental removal of woody debris from a forest gravel-bed stream

Effects on bedload transport of experimental removal of woody debris from a forest gravel-bed stream
This study, involving experimental removal of all woody debris larger than 1 cm in diameter, quantified the importance of debris with respect to bedload transport. This study also simulated possible effects of land management-related alterations
of the naturally occuring distribution of woody debris in streams. The study site is located on Chicagof Island, southeast Alaska.

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