Time-varying suspended sediment-discharge rating curves to estimate climate impacts on fluvial sediment transport

By estimating long-term suspended sediment discharges around river catchments, recovery periods of fluvial sediment transport after a large earthquake can be assessed. This study proved that the recovery period in a given catchment is positively correlated with the peak ground motions triggered by an earthquake. The correlation indicates that a recovery period of more than four years is required if a catchment is affected by an earthquake with a ground acceleration greater than 400 gal (~0.4 g). A total of four factors (sediment transport, seismic frequency, rock strength, and joint density) in the multivariate analysis were carefully considered to assess their influence on the sediment yield. As expected, runoff and geomaterial properties were the most important factors affecting the amount of suspended sediment discharges. The analysis of the influence factors further revealed that earthquake frequency is another important factor for sediment yield, especially within a few years after a large earthquake.

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Using Fluvial Sediment Transport Equilibrium to Drive Stream Restoration and Establish Sediment Load Reduction Targets

Proceedings of the Water Environment Federation ◽

10.2175/193864716819714933 ◽

2016 ◽

Vol 2016 (6) ◽

pp. 1224-1237

Author(s):

Scott Dierks ◽

Scott Isenberg

Keyword(s):

Sediment Transport ◽

Stream Restoration ◽

Sediment Load ◽

Load Reduction ◽

Fluvial Sediment ◽

Fluvial Sediment Transport

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Sediment slugs: large-scale fluctuations in fluvial sediment transport rates and storage volumes

Progress in Physical Geography Earth and Environment ◽

10.1177/030913339501900404 ◽

1995 ◽

Vol 19 (4) ◽

pp. 500-519 ◽

Cited By ~ 117

Author(s):

A.P. Nicholas ◽

P.J. Ashworth ◽

M.J. Kirkby ◽

M.G. Macklin ◽

T. Murray

Keyword(s):

Sediment Transport ◽

Sediment Supply ◽

Fluvial Systems ◽

Event Scale ◽

Fluvial Sediment ◽

Sediment Routing ◽

Basin Scale ◽

Wide Range ◽

And Storage ◽

Fluvial Sediment Transport

Variations in fluvial sediment transport rates and storage volumes have been described previously as sediment waves or pulses. These features have been identified over a wide range of temporal and spatial scales and have been categorized using existing bedform classifications. Here we describe the factors controlling the generation and propagation of what we term sediment slugs. These can be defined as bodies of clastic material associated with disequilibrium conditions in fluvial systems over time periods above the event scale. Slugs range in magnitude from unit bars (Smith, 1974) up to sedimentary features generated by basin-scale sediment supply disturbances (Trimble, 1981). At lower slug magnitudes, perturbations in sediment transport are generated by local riverbank and/or bed erosion. Larger-scale features result from the occurrence of rare high- magnitude geomorphic events, and the impacts on water and sediment production of tectonics, glaciation, climate change and anthropogenic influences. Simple sediment routing functions are presented which may be used to describe the propagation of sediment slugs in fluvial systems. Attention is drawn to components of the fluvial system where future research is urgently required to improve our quantitative understanding of drainage-basin sediment dynamics.

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