Short and long-term changes to bed mobility and bed composition under altered sediment regimes

Legacy effects on sediments in river corridors

“…Fig. 8A illustrates different levels of river response to reduced sediment supply, including bed coarsening Phillips et al, 2005), bank erosion (Hupp et al, 2009), altered bedform dimensions , channel incision (Harvey et al, 1983;Lach and Wyzga, 2002;Salant et al, 2006), altered channel cross-sectional geometry (Williams and Wolman, 1985;Magilligan et al, 2013) and planform (Surian, 1999;Graf, 2006;Dean and Schmidt, 2011;Gendaszek et al, 2012), and decreased rate of lateral channel migration through reduced point bar deposition (Brooks, 2003). Commonly, multiple channel responses occur through time.…”

“…8B). Bed fining (Osmundson et al, 2002;Salant et al, 2006), channel narrowing with vegetation encroachment (Ryan, 1997;Grams and Schmidt, 2002;Swanson et al, 2011), altered bedform type or dimensions (Magilligan and McDowell, 1997;Parker et al, 2003), bed aggradation (James, 1991;Ta et al, 2008), altered channel planform (Hilmes and Wohl, 1995), and enhanced floodplain sedimentation (Knox, 1972(Knox, , 1977(Knox, , 1987Clark and Wilcock, 2000;Florsheim and Mount, 2003;Knox, 2006) can all result from greater sediment supply. Work by Trimble (1974Trimble ( , 2013 in the Upper Mississippi Valley Hill country of the northcentral U.S. provides an example.…”

Sediment budget as affected by construction of a sequence of dams in the lower Red River, Viet Nam

“…The types, rates, and extents of channel degradation and aggradation downstream from dams are controlled by many factors, including regulated discharge rates and sediment load, channel geometry, channel material composition, and especially the discharge and sediment input provided by the river's tributaries (Michael and Thomas, 2001;Xu and Cheng, 2002;Doyle and Harbor, 2003;Gregory, 2006;Salant et al, 2006). Previous research works have mainly addressed river degradation (Chien, 1985;Galay et al, 1985;Kondolf, 1997), yet case studies on river aggradation remain scarce.…”

Long-term morphodynamic changes of a desert reach of the Yellow River following upstream large reservoirs' operation

“…Downstream of this initial degradation zone, the channel may exhibit aggradation. The types, rates, and extents of channel degradation and aggradation downstream from dams are controlled by many factors, including the regulated discharge rates and sediment load, channel geometry, channel material composition, and especially the discharge and sediment input provided by the river's tributaries (Hales et al, 1970;Simons and Li, 1982;Williams and Wolman, 1984;Knighton, 1987;Lane et al, 1996;James, 1997;Michael and Thomas, 2001;Xu, 2002;Doyle and Harbor, 2003;Gregory, 2006;Salant et al, 2006). Even in arid desert regions, potential input of windblown sand can also play an important role in river channel changes (Fig.…”