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  • Time-averaged flow structure in the central region of a stream confluence : a discussion
  • Channel geometry ; Confluent ; Fluvial hydrology ; Methodology ; Numerical model ; Stream ; Stream flow
  • This paper is a discussion of Rhoads and Kenworthy (1998) Time-averaged flow structure in the central region of a stream confluence, Earth Surface Processes and Landforms, 23, 171-191, that focuses upon the methods to identify secondary circulation
  • in river channel confluences. It argues that the use of the Rozovskii method can result in misleading conclusions about the nature of flow processes in confluences.
  • 1999
  • Biogenic process ; Biogeography ; Dam ; Fluvial processes ; Montana ; National park ; Rodent ; Sediment budget ; Sedimentation ; Stream ; Stream flow ; United States of America
  • This study provides additional data on sedimentation and stream flow in order to better understand the efficacy of beaver dams to trap sediment and alter the flow regime of streams, respectively. Data are collected on sedimentation depth (thickness
  • ) and volume, as well as stream velocity and discharge above and below beaver dams in eastern Glacier National Park (GNP), Montana. In addition, measurements of dam and pond morphology are examined in relation to sedimentation and flow alteration patterns.
  • 1999
  • Field observations on hyperconcentrated flows in mountain torrents
  • Alps (The) ; Carrying capacity ; Catastrophe ; Flood ; Germany ; Hydrodynamics ; Mountain ; Pic discharge ; Pyrénées ; Spain ; Stream ; Stream flow ; Torrent
  • The purpose of this paper is to report on observations of flow and sediment dynamics in hyperconcentrated flows during 2 extremely high magnitude events in relation with man-made constructions : the Arás flood which occurred in 1996 in the Central
  • 1999
  • A worldwide correlation for exponential bed particle size variation in subaerial aqueous flows
  • Alluvial cone ; Carrying capacity ; Correlation ; Experimentation ; Fluvial processes ; Grain size distribution ; Overland flow ; Runoff ; Sediment load ; Stream
  • The particle size of the bed sediments in or on many natural streams, alluvial fans, laboratory flumes, irrigation canals and mine waste deltas varies exponentially with distance along the stream. A plot of the available worldwide exponential bed
  • particle size diminution coefficient data against stream length is presented which shows that all the data lie within a single narrow band extending over virtually the whole range of stream lengths and bed sediment particle sizes found on Earth.
  • 1999
  • Channel geometry ; Confluent ; Fluvial hydrology ; Methodology ; Numerical model ; Stream ; Stream flow
  • In this response to Lane et al. (1999) Time averaged flow structure in the central region of a stream confluence : a discussion, Earth Surface Processes and Landforms, 24, 361-367, the AA. show that their method for decomposing the cross-stream
  • , helical motion to the pattern of cross-stream flow at confluences.
  • 1999
  • Three-dimensional structure of flow at a confluence of river channels with discordant beds
  • Canada ; Carrying capacity ; Confluent ; Model ; Quebec ; Runoff ; Sediment transport ; Spatial variation ; Stream ; Turbulence
  • This paper presents data on the detailed structure of three-dimensional mean and turbulent flow for different hydraulic conditions at the confluence of natural rivers with discordant beds. The objectives of the paper are : 1) to describe the three
  • -dimensional field of flow at a junction of natural channels; 2) to assess the role of changes in bed morphology that occur during transport-effective events on the structure of flow at a confluence; and 3) to examine how the structure of three-dimensional flow
  • varies with changes in the ratio of momentum flux between the two confluent streams.
  • 1999
  • Worldwide correlations for subaerial aqueous flows with exponential longitudinal profiles
  • Alluvial cone ; Channel geometry ; Correlation ; Delta ; Grain size distribution ; Longitudinal section ; Sediment load ; Stream ; World
  • Recently, it has been shown that a very strong worlwide correlation exists between exponential bed particle size diminution coefficients for mobile bed subaerial aqueous flows of all kinds and the lengths of the corresponding stream segments
  • . Together, this correlation and the exponential profile and particle size diminution relationships suggest that a complementary worldwide correlation may exist for the bed concavity coefficients of such flows. In this paper, it is shown that worldwide
  • correlations exist between these bed concavity coefficients and both the corresponding stream segment lengths and bed particle size diminution coefficients.
  • 1999
  • Cyclicity in precipitation and stream discharge in Georgia and relationships with the southern oscillation
  • Climate oscillation ; Discharge ; Georgia (USA) ; Ocean atmosphere interaction ; Precipitation ; Spectral analysis ; Stream ; Teleconnection ; Time series ; Twentieth Century ; United States of America ; Water cycle ; Watershed
  • The AA. examine both the cyclic and SO effects on precipitation and stream flow in Georgia with a view to better understanding the vagaries of hydrological conditions. To achieve these objectives, stream discharge at 10 U.S. Geological Survey stream
  • 1999
  • Arid area ; Australia ; Braided channel ; Carrying capacity ; Channel geometry ; Floodplain ; Grain size distribution ; Northern Territory ; Riparian vegetation ; Sediment load ; Stream ; Stream flow
  • to the formation and maintenance of anabranching river patterns; and third, to consider the implications of anabranching for flow and sediment discharge.
  • 1999
  • From GCMs to river flow : a review of downscaling methods and hydrologic modelling approaches
  • Atmospheric circulation ; Climatic variation ; Global change ; Hydrology ; Impact ; Methodology ; Model ; Stream flow ; Water resources
  • 1999
  • Bank erosion ; Geotechnics ; Hydrodynamics ; Italy ; Mass movement ; Porosity ; Precipitation ; Stream ; Stream flow ; Toscana
  • This paper makes use of the monitoring and modelling results to determine the variability of pore water pressures in a streambank at a seasonal scale and evaluate their response to rainfall and single flow events : to evaluate the contribution
  • of matric suction to increase shear strength in partly saturated material and assess the role of suction in determining bank stability; to determine the influence of reduction in matric suction during flow events in causing instability and triggering mass
  • 1999
  • Soil erosion by surface water flow on a stony, semiarid hillslope
  • over a wide range of slopes and discharge rates. The measurements were used to evaluate flow velocity as a function of slope, discharge and rock cover, and to evaluate soil detachment rates as a function of hydraulic shear stress, stream power
  • The objectives of this study were to evaluate the hydraulics and erosion by surface water flow of stony soil in a semiarid, rangeland environment. Methods for directly measuring rill erosion rates on undisturbed soil surfaces allowed measurements
  • 1999
  • Channel geometry ; Ecosystem ; Human impact ; Hydraulic works ; Meander ; Riparian vegetation ; Stream ; Stream flow ; United Kingdom ; Wales
  • 1999
  • Hydrodynamics ; River bed ; Stream ; Stream flow ; Terek ; Turbulence ; Volga
  • 1999
  • Carrying capacity ; Colorado ; Comparative study ; Methodology ; Sediment budget ; Sediment load ; Stream ; United States of America
  • on the sampler used and, therefore, they are not directly comparable without some mode of calibration. To place this finding in a larger context, sediment rating curves, determined from weights of samples and measurements of flow, were integrated over available
  • flow records and used to estimate annual yield. Discussion of the results.
  • 1999
  • Carrying capacity ; Confluent ; Hydrodynamics ; Model ; Numerical model ; Roughness ; Stream ; Stream flow ; Turbulence
  • This paper addresses the recent trend in fluvial geomorphology towards using computational fluid dynamics to explore the adjustment between flow processes, sediment transport and river channel morphology. It aims to evaluate the extent to which 3D
  • 1999
  • Botswana ; Carrying capacity ; Fluvial dynamics ; Grain size distribution ; Pic discharge ; Sediment load ; Spatial distribution ; Stream ; Stream flow ; Tracer
  • emphasis on the three-dimensional dispersal of gravels, patterns of scour and fill and depth of active layer. Two major flow events of equivalent magnitude occurred, moving the tagged particles in December 1987 and in March 1991. Discussion of the results
  • 1999
  • Arctic Region ; Biogenic process ; Marginal sea ; Nitrogen ; Phosphate ; Sea ; Solution load ; Stream ; Stream flow ; Underground flow
  • 1999
  • Amudarya ; Arid area ; Delta ; Human impact ; Runoff ; Stream flow ; Syr Darya ; Water balance
  • 1999
  • Discharge ; Fluvial hydrology ; Island ; Seychelles ; Stream ; Stream flow ; Water cycle ; Watershed
  • 1999