Meandering channel dynamics in highly cohesive sediment on an intertidal mud flat in the Westerschelde estuary, the Netherlands

Kleinhans, Maarten G.; Schuurman, F.; Bakx, Wiecher; Markies, H.

doi:10.1016/j.geomorph.2008.10.005

Cited by 81 publications

(86 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Best and Reid, 1984), downstream of bars in bedrock controlled canyons (Schmidt, 1990;Schmidt et al, 1993;Wright and Kaplinski, 2011) and in river bends (e.g. Bagnold, 1960;Leeder and Bridges, 1975;Hickin, 1977Hickin, , 1978Hickin, , 1986Hickin and Nanson, 1984;Jackson, 1992;Andrle, 1994;Hodskinson and Ferguson, 1998;Ferguson et al, 2003;Kleinhans et al, 2009;Rhoads and Massey, 2012;Parsons, 2003;Vietz et al, 2012;Schnauder and Sukhodolov, 2012).…”

Section: Problem Definition and Objectivementioning

confidence: 99%

“…This 'sharp bend style' of river bend development is often associated with channels that have relatively strong banks and limited meandering dynamics (Ferguson, 1987;Kleinhans et al, 2009;see Kleinhans, 2010, for review), but have also been observed in channels that are more laterally active (Hickin and Nanson, 1975;Hodskinson and Ferguson, 1998;Ferguson et al, 2003). According to Leeder and Bridges (1975), inner-bank flow separation is largely controlled by the ratio of channel width to centreline radius of curvature, B/R and the Froude number Fr, whereby an increase in bend tightness and Froude number favours flow separation.…”

Section: Reviewmentioning

confidence: 99%

“…by Hickin (1977) on the Beatton River, by Hickin (1978) on the Squarmisch River, by Hickin and Nanson (1984) on various rivers in western Canada, by Jackson (1992) on the Fall River, by Hodskinson and Ferguson (1998) on the Allt Dubhaig, by Vietz et al (2012) on the Ovens River, by Schnauder and Sukhodolov (2012) on the Tollense River, by Parsons (2003) on lowland sinuous channels in north England, and in small sinuous channels on intertidal mud flats (Kleinhans et al, 2009). Flow separation at the outer bank can be driven by an adverse water surface gradient at the outer bank (Blanckaert, 2010).…”

Section: Configuration Measured Physical Quantitiesmentioning

confidence: 99%

See 2 more Smart Citations

Flow separation at the inner (convex) and outer (concave) banks of constant‐width and widening open‐channel bends

Blanckaert

Kleinhans

McLelland

et al. 2012

Earth Surf Processes Landf

Self Cite

View full text Add to dashboard Cite

There is a paucity of data and insight in the mechanisms of, and controls on flow separation and recirculation at natural sharply-curved river bends. Herein we report on successful laboratory experiments that elucidate flow structure in one constant-width bend and a second bend with an outer-bank widening. The experiments were performed with both a flat immobile gravel bed and mobile sand bed with dominant bedload sediment transport.In the constant-width bend with immobile bed, a zone of mainly horizontal flow separation (vertical rotational axis) formed at the inner bank that did not contain detectable flow recirculation, and an outer-bank cell of secondary flow with streamwise oriented rotational axis. Surprisingly, the bend with widening at the outer bank and immobile bed did not lead to a transverse expansion of the flow. Rather, flow in the outer-bank widening weakly recirculated around a vertical axis and hardly interacted with the inner part of the bend, which behaved as a constant-width bend.In the mobile bed experiment, downstream of the bend apex a pronounced depositional bar developed at the inside of the bend and pronounced scour occurred at the outside. Moreover the deformed bed promoted flow separation over the bar, including return currents. In the constant-width bend, the topographic steering impeded the generation of an outer-bank cell of secondary flow. In the bend with outer-bank widening, the topographic steering induced an outward expansion of the flow, whereby the major part of the discharge was conveyed in the central part of the widening section. Flow in the outer-bank widening was highly three dimensional and included return currents near the bottom.In conclusion, the experiments elucidated three distinct processes of flow separation common in sharp bends: flow separation at the inner bank, an outer-bank cell of secondary flow, and flow separation and recirculation in an outer-bank widening.

show abstract

Section: Problem Definition and Objectivementioning

confidence: 99%

Section: Reviewmentioning

confidence: 99%

Section: Configuration Measured Physical Quantitiesmentioning

confidence: 99%

See 1 more Smart Citation

Flow separation at the inner (convex) and outer (concave) banks of constant‐width and widening open‐channel bends

Blanckaert

Kleinhans

McLelland

et al. 2012

Earth Surf Processes Landf

Self Cite

View full text Add to dashboard Cite

show abstract

“…7). Strong tidal currents alone will drive patterns of erosion and redeposition (meanders) in tidal wetlands (Biggs 1982;Kearney et al 1988;Kleinhans et al 2009), resuspending and removing sediment from the marsh (Wang 2002;Larsen et al 2009). Altered hydrology induces continuing shifts in tidal flows end river courses, and therefore neighboring wetlands, by altering sediment transport (Teal Table 6 The results of a Wilcox rank-sum test for marsh loss from 1966 *Significance after using false recovery control to adjust the critical P value for significance with these multiple tests (Benjamini and Hochberg 1995) Fig.…”

Section: Discussionmentioning

confidence: 99%

“…However, many natural forces are also erosive, including waves formed by winds over long stretches of water (Pye 1995;Schwimmer 2001;Leonardi et al 2016), but these waves can be larger when water becomes deepened by sealevel rise, excessive dredging, or other reasons. Tidal currents can induce meander patterns of erosion and redeposition (Biggs 1982;Kearney et al 1988;Kleinhans et al 2009) and wind-driven wave action can also have strong effects (Fagherazzi and Wiberg 2008;Leonardi and Fagherazzi 2014;Priestas et al 2015). The interaction of sea-level rise and sediment deposition rates can also cause the widening of creeks (Fagherazzi et al 2012).…”

Section: Communicated By Carles Ibanez Martimentioning

confidence: 99%

Long-Term Erosional Trends Along Channelized Salt Marsh Edges

Browne

2017

Estuaries and Coasts

View full text Add to dashboard Cite

Salt marshes provide important habitats for many species in the estuaries along the east and Gulf coasts of North America. With many species dependent on these coastal marshlands and extensive documentation that these marshlands are disappearing, a clear understanding of the mechanisms causing loss is critical. Much of the salt marsh was lost to reclamation and construction before these activities were curtailed circa 1970; however, losses due to other causes have continued and multiple hypothesized causes have been proposed, not all mutually exclusive. Yet it remains unclear whether there are legacy effects from the reclamation projects. When the edges of salt marshes are cut into, and gentle vegetated slopes are replaced by sharp edges adjoining deep water of 2 m or more, erosion could accelerate and could continue for many years. One method that may help shed light on the relative importance of the various causes of salt marsh erosion would be to compare the erosion rates of specific edges within a marshland that are exposed to particular conditions. We therefore used several sets of aerial photography spanning 84 years to track the changes at specific edge locations along marsh edges and then make comparisons between anthropogenically created edges and naturally created edges, including comparisons within use and width categories of navigational channels. Erosion rates were found to remain significantly higher on channelized edges than along otherwise similar wetland edges even several decades after modification. Likely reasons include the continued exposure of underlying layers that lack reinforcing plant root systems, vertical edges that are more vulnerable to undermining from wave action, and increased erosion related to altered tidal flows.

show abstract

Hydro‐sedimentological processes in meandering rivers

Blanckaert

2018

Fluvial Meanders and Their Sedimentary Products in the Rock Record

View full text Add to dashboard Cite

Meandering channel dynamics in highly cohesive sediment on an intertidal mud flat in the Westerschelde estuary, the Netherlands

Cited by 81 publications

References 37 publications

Flow separation at the inner (convex) and outer (concave) banks of constant‐width and widening open‐channel bends

Flow separation at the inner (convex) and outer (concave) banks of constant‐width and widening open‐channel bends

Long-Term Erosional Trends Along Channelized Salt Marsh Edges

Hydro‐sedimentological processes in meandering rivers

Contact Info

Product

Resources

About