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  • Multi-scale characterization and evolution of channel forms in gravel-bed rivers
  • Supplementary data confirming the relationship between critical Shields stress, grain size and bed slope
  • Experimentation ; Grain size distribution ; Hydrological regime ; River bed ; Runoff ; Scotland ; Sediment transport ; Slope gradient ; Stream flow ; Threshold ; United Kingdom
  • This paper presents new experimental data on threshold conditions for motion of coarse uniform sediments. The experiments were conducted with gravel in a flume and included measurements of hydraulic characteristics and rate of bed particle movement
  • for a range of flows at different bed slopes. A reference transport method was used to define the beginning of sediment motion. The experimental data confirm the recent finding that the critical Shields stress for motion of coarse uniform sediment varies
  • with both grain size and bed slope.
  • Measuring bedload in gravel-bed mountain rivers : averaging methods and sampling strategies
  • A dataset of more than 1,000 individual bedload samples coupled with hydraulic flow variables (water depth and velocity) was collected on 2 high mountain rivers the torrent de Saint Pierre, a proglacial gravel-bed river in the French Alps, in July
  • 2002 and the Urumqi River, in the Chinese Tianshan mountains during summer 2005 and 2006. Analysis of the dataset leads to question the usual section averaged sampling procedure of bedload using Helley-Smith type bedload sampler. It is shown
  • Evaluation of bedload yield in gravel-bed rivers using scour chains and painted tracers : the case of the Esconavette Torrent (Southern French Prealps)
  • The event-based bedload yields of a small gravel-bed river (the Esconavette Torrent) have been concomitantly determined by surveying coarse sediment deposition in a trap and by monitoring the active layer of the bed and the displacement of painted
  • Bed mobility on the Deshutes River, Oregon : tracer gravel results
  • Here, the AA. report their experience of using exotic gravel tracers (quartz particles) on the lower Deschutes River, Oregon, to obtain direct evidence of the threshold for bed mobility over 4 runoff seasons. They compared the bed mobility estimates
  • Gravel bedload transport rates were measured at 8 study sites in coarse-bedded Rocky Mountain streams using 4-6 bedload traps deployed across the stream width and a 76 by 76 mm opening Helley Smith sampler. Differences in sampler opening size
  • and sampling time contribute to the measured differences, but the biggest effect is likely attributable to the bedload traps being mounted on ground plates thus avoiding direct contact between the sampler and the bed and preventing involuntary particle pick up.