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Par Collection Par Auteur Par Date Par Sujet Par Titre
  • Critical flow in rockbed streams with estimated values for Manning's n - Comment and reply
  • Hydrodynamics ; Slope gradient ; Stream ; Stream flow
  • H. Chanson comments some aspects of the Tinkler's paper (1997) regarding critical flow, critical slope calculations and boundary shear stress distributions in undular flows, and K.J. Tinkler replies in turn.
  • 1998
  • Time-averaged flow structure in the central region of a stream confluence
  • Carrying capacity ; Channel geometry ; Confluent ; Fluvial dynamics ; Fluvial hydrology ; Illinois ; Runoff ; Stream flow ; United States of America
  • This paper examines the time-averaged, two-dimensional (downstream and cross-stream) flow sructure within the central region of the confluence hydrodynamic zone (CHZ) at a small stream confluence with an asymmetrical planform. It also examines how
  • flow structure in this part of the CHZ varies with changes in hydrologic conditions and bed morphology. A particular focus is to document the presence or absence of time-averaged, helical motion in the central region of the confluence.
  • 1998
  • A comparison of flow intensities in alluvial rivers : characteristics and implications for modelling flow processes
  • Forecast ; Least squares method ; Linear regression ; Methodology ; Model ; Stream ; Stream flow ; Turbulence
  • This paper compares flow intensity data obtained with different instruments from a variety of fluvial environments. It examines associations between the root-mean-square of longitudinal velocity fluctuations (flow intensity), local mean velocity
  • , relative depth, and boundary resistance. Preliminary approaches to prediction and modelling of variations in flow intensity are suggested based upon linear regression relationships.
  • 1998
  • Effects of a pebble cluster on the turbulent structure of a depth-limited flow in a gravel-bed river
  • Canada ; Gravel ; Hydrodynamics ; Micromorphology ; Quebec ; Stream ; Stream flow ; Turbulence
  • This paper presents original results from measurements of velocity taken at a high spatial and temporal resolution in a turbulent flow upstream and downstream from a pebble cluster. The high sampling resolutions in a natural environment permitted
  • characterization of the complex dynamics of the turbulent flow in the vicinity of the cluster. The description of these dynamics is based on the interpretation of contour maps of several turbulence statistics. Results indicate the existence of highly dynamic
  • boundaries between zones where strong intermittent events are generated. They also highlight the difference between shedding and upwelling motions of the flow.
  • 1998
  • A study of physico-geographical factors for formation of hyperconcentrated flows in the Loess Plateau of China
  • Aeolian deflation ; Aeolian features ; China ; Loess ; Plateau ; Runoff ; Seasonal variation ; Stream ; Stream flow ; Suspended load ; Topography ; Vegetation
  • Most of the data used in this study come from hydrometric stations in the Yellow River basin. The purpose of this study is to elucidate the formation of hyperconcentrated flow in relation to physico-geographical factors at macro spatial scales, so
  • this paper is focused on hyperconcentrated flows in river channels only, and does not discuss those on slopes or in gullies.
  • 1998
  • Strontium isotope ratios in streams and the effect of flow rate in relation to weathering in catchments
  • To provide more detail information on the effect of flow rate on strontium isotope ratios, the Sr 87/Sr 86 ratio was measured in streamwater samples taken at low and high flow rates and also in samples taken at four and eight hourly intervals during
  • 1998
  • Fluvial dynamics ; Geosystem ; River bed ; Spatial variation ; Stream ; Stream flow
  • 1998
  • Carrying capacity ; Fluvial dynamics ; Gravel ; Montana ; Mountain ; Shear stress ; Stream ; Stream flow ; Turbulence ; United States of America
  • transport events associated with the daily rise and fall in stream discharge were investigated. This paper reports the results of this study designed to describe fully the adjustment of river bed and turbulent flow to the unsteady passage of a pebble bedload.
  • 1998
  • Australia ; Braided channel ; Carrying capacity ; Channel geometry ; Riparian vegetation ; Sand ; Stream ; Stream flow ; Tropical zone ; Western Australia
  • This paper examines the existence of sand-dominated ridge-form anabranching rivers in the Kimberley region of Western Australia. It describes their channel and ridge morphology, sedimentology and stratigraphy, discusses stream flow and sediment
  • 1998
  • On the nature of spatial and temporal variations of bedload transport in a gravel-bed stream
  • Carrying capacity ; Flood ; Fluvial hydrology ; Montana ; Mountain ; Rocky Mountains ; Roughness ; Seasonal variation ; Sediment load ; Stream ; Stream flow ; United States of America
  • To obtain an understanding of the hitherto unknown high resolution, continual temporal and spatial nature of bedload transport in gravel-bed streams, measurements were undertaken over 2 magnetically sensitive bedload detector logs at Squaw Creek
  • in Montana. The aim was to measure the transfer of particles continuously over the 2 spatially differentiated detectors during normal as well as flood flows and to suggest some controls on this process.
  • 1998
  • Three-dimensional measurement of river channel flow processes using acoustic doppler velocimetry
  • Technical and software bulletin 1998
  • Braided channel ; Discharge ; Fluvial hydrology ; Methodology ; Roughness ; Salinity ; Scotland ; Stream ; Stream flow ; Switzerland ; United Kingdom ; Water quality
  • This paper describes and assesses : 1) the use of a new instrument for the determination of three-dimensional flow velocities in natural rivers, the acoustic Doppler velocimeter (ADV); and 2) a method for positioning and orienting such measurements
  • relative to a single local coordinate system to relate flow velocity factors with the bed and water surface. The ADV uses the Doppler shift priciple to measure the velocity of small particles , assumed to be moving at velocities similar to the fluid.
  • 1998
  • Gravel ; Methodology ; Mountain ; River bed ; Roughness ; Sand ; Shear stress ; Stream ; Stream flow ; Switzerland ; Turbulence ; Valais
  • The aim of this study is to simulate the uncertainty that arises from using the law of the wall in shallow streams, using a specific case-study to assess the extent to which estimates could be in error. More particularly, the effects on bed shear
  • stress of varying 1) the range of flow depths from which observations are obtained, and 2) the lowest elevation of a measurement point above the bed, are examined. These issues are investigated using a high vertical definition of velocity measurements
  • taken in a stream with mixed sand and gravel bed.
  • 1998
  • Flood ; Fluvial hydrology ; Model ; Poland ; Probability ; Statistics ; Stream ; Stream flow
  • The objective of flood frequency analysis is to relate the magnitude of annual peak flow discharges to their frequency of occurrence through the use of probability distributions. In this study a time trend is investigated in the first two moments
  • 1998
  • Braided stream aggradation on an alluvial fan margin : Emerald Lake fan, British Columbia
  • Alluvial cone ; Braided channel ; British Columbia ; Canada ; Cold area ; Fluvial processes ; Grain size distribution ; Meltwater ; Pic discharge ; Sediment transport ; Stream flow ; Summer
  • 1998
  • British Columbia ; Canada ; Carrying capacity ; Flood ; Gravel ; Island ; Methodology ; Porosity ; River bed ; Sediment transport ; Stream ; Stream flow ; Tracer ; Vancouver
  • 1998
  • Carrying capacity ; Colorado ; Discharge ; Grain size distribution ; Gravel ; Hydrodynamics ; Mountain ; Rocky Mountains ; Sand ; Stream ; Stream flow ; Turbulence ; United States of America
  • This study focused on whether or not bedload discharges and size distributions are responsive to changes in flow, either at-a-point or across a section, in the East St. Louis Creek watershed, Colorado. Because of the limitations of the Helley-Smith
  • 1998
  • Relationships between flow hydraulics, sediment supply, bedload transport and channel stability in the proglacial Virkisa River, Iceland
  • Braided channel ; Carrying capacity ; Channel geometry ; Cold area ; Glacial surge ; Iceland ; Sediment transport ; Stream
  • is controlled by low frequency, high magnitude flow events, possibly associated with glacial outburst floods. This is in marked contrast to process-form relationships in more dynamic alpine proglacial channels that are characterised by high rates of sediment
  • 1998
  • Braided channel ; Canada ; Channel geometry ; Floodplain ; Lake ; Meander ; Model ; Runoff ; Saskatchewan ; Stream ; Stream flow
  • 1998
  • Asian part of Russia ; Eastern Siberia ; Flood ; Fluvial hydrology ; Inundation ; Runoff ; Stream ; Stream flow ; Valley
  • 1998
  • A multi-stream analysis of the changing pattern of interregional migration in Great Britain, 1960-1991
  • Counterurbanization ; Great Britain ; Internal migration ; Interregional migration ; Migration factor ; Migratory balance ; Migratory flow ; Model ; Spatial interaction ; United Kingdom
  • 1998