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  • Unimpaired and regulated discharge in the Sacramento River Basin, California
  • California ; Dam ; Discharge ; Fluvial hydrology ; Hydraulic works ; United States of America ; Watershed
  • Reservoirs alter monthly and annual discharge quantities in the Sacramento River Basin of northern California and this practice obscures the natural variability of river discharge. - (DWG)
  • Critical discharge for entrainment of poorly sorted gravel
  • Carrying capacity ; Discharge ; Fluvial dynamics ; Fluvial hydrology ; Fluvial processes ; Stream flow
  • Entrainment criteria for gravel-sized particles on river beds are usually defined in terms of shear stress, but some workers have proposed that critical-discharge relationships are more reliable and more convenient. Comparisons with published data
  • on critical discharges in a variety of rivers show that both the sensitivity of critical discharge to grain size, and the absolute levels of critical discharge, are predicted quite well. However, any prediction of critical discharge is sensitive
  • Effective discharge and gravel-bed rivers
  • Carrying capacity ; Colorado ; Discharge ; Fluvial hydrology ; Gravel ; Meltwater ; Mountain ; Rocky Mountains ; Sediment load ; Stream ; United States of America
  • Rivers with constraints on the mobility of bed material, typically armoured channels with steeper than average relationship of bedload discharge to water discharge, may have an effective discharge occuring at higher stages and greater recurrence
  • intervals than bankfull discharge. Bedload discharges were measured at 5 snow-melt dominated, gravel-bedded rivers in the northern Rocky Mountains, USA. Data indicate that, as the exponent of the bedload rating increases from typical to more steep values
  • , effective discharge increases from near-bankfull discharge to, in this study, about 1.3 bankfull discharge. This represents about a doubling of the recurrence interval.
  • The impact of climate on the discharge of the River Rhine
  • Climate ; Climatic variability ; Discharge ; Europe ; Impact ; Model ; Rhine ; Stream ; Water balance
  • In this book a first attempt has been made to provide a more detailed, quantitative assessment of the sensitivity of the River Rhine discharge to climate change. The attempt indicates the order of magnitude of the effect of a climatic change
  • . In this respect the sensitivity of the river has been analysed, a spatially distributed water balance model has been developed and finally discharge scenarios are assessed. - (AGD)
  • Bankfull discharge recurrence interval in gravel-bed rivers
  • Belgium ; Discharge ; Fluvial dynamics ; Fluvial hydrology ; Hydrological regime ; Inundation ; Lithology ; Stream ; Watershed
  • 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.
  • Characteristics of sediment discharge in the subarctic Yukon River, Alaska
  • Alaska ; Cold area ; Discharge ; Meltwater ; Periglacial features ; Permafrost ; Seasonal variation ; Stream ; Suspended load ; Turbidity ; Yukon
  • The characteristics of sediment discharge in the Yukon River were investigated by monitoring water discharge, water turbidity and water temperature. The AA. use observational results of 1999 to characterize the Yukon sediment discharge and discusses
  • Teaching the hydrologic and geomorphic significance of drainage basins and discharge in physical geography
  • Channel geometry ; Discharge ; Fluvial erosion ; Fluvial hydrology ; Hawaii ; Physical geography ; Suspended load ; Teaching of geography ; Watershed
  • Develops two sets of exercises, one of which is field-monitored, to enhance student understanding of water and sediment discharge. - (DWG)
  • Velocity-discharge relationships in three lowland rivers
  • The use of different functional forms to describe the variation of velocity with discharge is explored for four cross-sections, nine short reaches (100-250 m), and three long reaches (2-7 km) in three lowland rivers in Lincolnshire.
  • An alternative measure of discharge effectiveness
  • Carrying capacity ; Discharge ; Fluvial hydrology ; Hydrological regime ; Illinois ; Methodology ; Sediment budget ; Stream ; Suspended load ; United States of America
  • Here the AA. develop an analytical expression for various discharge metrics, and apply this approach to a series of suspended sediment load data sets. They then develop a general expression for a newly proposed dicharge metric, the functional
  • -equivalent discharge, Qfed. The AA. describe how Qfed varies broadly with sediment and hydrologic conditions.
  • California ; Discharge ; Fluvial hydrology ; Human impact ; Hydraulic works ; Hydrological regime ; Precipitation ; Seasonal variation ; United States of America ; Watershed
  • Reconstructed or unimpaired discharges for 1921 to 1994 for the Sacramento River are employed as an indicator of natural discharge and are analyzed for evidence of seasonal change with 2 questions : 1) are seasonal hydroclimate changes evident
  • in Sacramento River Basin unimpaired discharges? 2) if changes are evident, when did the change in unimpaired discharges first appear?
  • Vztahy mezi kolisanim srazek a odtoku na uzemi CSR podle rad mesicicnich hodnot. (Relation between variations of precipitation and discharge rates on the territory of the C.S.R. according to series of monthly values)
  • The study presents the results of analysis of precipitation and discharge rates in C.S.R. of spatial monthly sums in Bohemia (mean monthly discharge rates of the Elbe at Decin in the period of 1877-1981) and in Moravia (discharges rates
  • Determination of bankfull discharge magnitude and frequency : comparison of methods on 16 gravel-bed river reaches
  • Channel geometry ; Discharge ; Flood ; Floodplain ; France ; Garonne ; Hydrodynamics ; Loire ; Recurrence interval ; Seine ; Stream ; Stream flow
  • The aim of this paper is to test and analyse the sensitivity of : bankfull discharge magnitude according to the choice of bankfull elevation definition at river reach scale; bankfull discharge duration and frequency of exceedance according
  • Spatial and scale-dependent controls on North American Pan-Arctic minimum river discharge
  • Alaska ; Arctic Region ; Canada ; Climatic change ; Discharge ; Fluvial hydrology ; Model ; North America ; Northwest Territories ; Scale ; Spatial analysis ; Stream ; Watershed
  • Spatial patterns of minimum monthly river discharge in the North American Pan-Arctic and its potential controls are explored with geographically weighted regression (GWR). Minimum discharge is indicative of soil water conditions; therefore
  • with annual mean river discharge, temperature at time of minimum discharge, and biome describes well the spatial patterns in minimum discharge. However, minimum discharge in larger watersheds is influenced more by temperature and biome distributions than
  • it is in small basins, suggesting that scale is critical for understanding minimum river discharge.
  • Predicted wetted width in any river at any discharge
  • Channel geometry ; Cross section ; Discharge ; Ecosystem ; Habitat ; Hydrology ; Model ; New Zealand ; Stream
  • In this paper, patterns in at-a-station hydraulic geometry are analysed using observed field data on width and discharge together with mapped catchment characteristics such as catchment area and climate. The aim of the paper is to estimate
  • the parameters for the at-a-station relationship between discharge and width at ungauged sites, and the variation around this relationship. The purpose of this work was to produce a method for predicting width over a range of discharges for applications
  • Use of the discharge-weighted average velocity in studies of the frictional energy loss of streamflow
  • Cross section ; Discharge ; Fluvial hydrology ; Mathematical hydrology ; River bed ; Roughness ; Sediment load ; Stream flow
  • Existing resistance equations are designed, and have been historically used, to estimate discharge from manufactured conduits and streambeds which resemble them. They produce a value for the area-weighted average velocity, which can
  • then be multiplied by the cross-sectional area to produce an estimate of discharge. In more recent times, researchers have also begun to study energy loss, a use for which the area-weighted average is inappropriate. The discharge-weighted average velocity
  • Suspended sediment discharge in subsurface flow from the head hollow of a small forested watershed, northern Japan
  • Surface flow and suspended sediment discharge from the head hollow of the Jozankei Experimental Watershed in Hokkaido were measured to clarify the implications of subsurface hydrology for soil movement. Subsurface discharges during the extremely
  • flux and rate of change in subsurface discharge were in inverse proportion to initial subsurface discharge before the storm runoff and they represented rare seasonal variation.
  • Estimate of long-term sediment discharge at tidal inlets using water level data from a tide gauge
  • It is the purpose of this contribution to develop a simple, low cost approach to the estimate of sediment discharge through the entrance channel. Such a method is based upon an understanding of the hydroynamic behaviour of tidal inlets. According
  • to this approach, a time-series of water level data from a single tide gauge located at a harbour entrance, together with data sets for wave climates and freshwater discharges, can be analysed to estimate sediment discharges. An example of the application
  • of this method, to estimate annual bedload discharges from Christchurch Harbour (southern England), is described.
  • Discharge and sedimentation periodicities in small sized watersheds
  • Discharge ; Experimental catchment ; Periodicity ; Runoff ; Sediment transport ; Sedimentation ; Semi-arid area ; Texas ; Turbulence ; United States of America ; Watershed
  • The AA. used wavelets to analyze the measured discharge and sedimentation during 2001 from the nested Agricultural Research Service watershed in Riesel, Texas. Periodicities from wavelet spectra were interpreted in terms of experiments conducted
  • on granular particle systems. The major transformation processes of discharge periodicity during sedimentation are : shifting, fragmentation, and recombination. Recombination was seen to occur in discharges that were dominated by transport (routed) flows.
  • Bankfull discharge in mountain streams : theory and practice
  • Carpathian Mountains ; Discharge ; Flood ; Methodology ; Mountain ; Poland ; Riparian vegetation ; Stream
  • The results are presented of an investigation of bankfull discharge in two Polish Carpathian streams : Skawica and Krzyworzeka. Existing definitions of river bankfull were reviewed and applied in tests carried out on selected cross-sections
  • concludes that bankfull discharge value for a mountain stream should not be reported as a single number, but rather as a range of discharges within which one could expect the bankfull value to lie.
  • Himalayan deforestation, changing river discharge, and increasing floods : myth or reality
  • Neither precipitation nor discharge data from the Chenub and other headwater streams validates the oft-repeated assertion that flooding on the Gengetic plain has increased (even though flood damage has increased). - (DWG)