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  • The dominance of dispersion in the evolution of bed material waves in gravel-bed rivers
  • This paper summarizes recent theoretical models, experiments and field studies that have been designed specifically to measure relative rates of dispersion and translation of bed material waves. In considering uniform channels only, and also
  • in disregarding exchanges of sediment between a channel and its floodplain, 2 factors influence wave behaviour : interactions between flow, wave topography and bed load transport; and relative particle sizes of input sediment and pre-existing bed material
  • . The results indicate that dispersion dominates the evolution of bed material waves in gravel-bed channels.
  • Determination of the sediment transport in an armoured gravel-bed river
  • -discharge (Qb/Q) relationships are determined by local bed-load transport in the Common Meuse. The survey data in the Common Meuse were analysed with a geographical information system (GIS) (ARC-INFO) to produce maps of the river-bed level. The subtraction
  • of maps of bed levels in different years results in a map with spatial distributions of erosion and sedimentation.
  • Effective discharge and gravel-bed rivers
  • 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
  • Toward a practical method for estimating sediment-transport rates in gravel-bed rivers
  • Experimentation ; Fluvial dynamics ; Fluvial erosion ; Loess ; Numerical model ; Porosity ; River bed ; Stream ; United States of America