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Showing 1 to 20 of 45 for “"gravel bed"”.
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Cottonwood Establishment in a Gravel-Bed River
… pristine, 5th order, wandering floodplain of the gravel-bed Flathead River, Montana, USA. The focus of my research was to determine the mechanisms explaining successful recruitment on recently formed, unvegetated bars, covering a range of spatial scales from within-bar (~ 1 to 10 m) to …
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Cottonwood Establishment in a Gravel-Bed River
… pristine, 5th order, wandering floodplain of the gravel-bed Flathead River, Montana, USA. The focus of my research was to determine the mechanisms explaining successful recruitment on recently formed, unvegetated bars, covering a range of spatial scales from within-bar (~ 1 to 10 m) to …
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Adhesive areal sampling of gravel bed streams
… linked to the material that makes up its channel bed. Usually, a vertical stratification by particle size can be recognized. The presence a coarser surface layer is considered to be one of the most important features of a gravel bed stream. Since this surface layer consists of a distinct …
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Sampling spatial sediment variation in gravel-bed streams
A gravel-bed stream's grain size distribution plays an important role in determining a river's depth, sediment transport rates, and stream bed stability as well as the survival rates of mussels and salmonids. Unfortunately, the material found in gravel-bed rivers exhibits vertical stratification as …
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Numerical Modelling of Braiding Processes in Gravel-Bed Rivers
Gravel-bed braided rivers are distinctive natural environments that provid a wide range of key environmental, economic and recreational services. There is, however,a growing concern that over the twentieth century, an increasing number of braided rivers have metamorphosed into wandering or single …
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Modelling fine sediment transport over an immobile gravel bed
… not limited to the alluvial rivers with sandy beds. A variety of natural or human actions, such as fire, logging, flow diversion, road construction, and urban or agricultural development can increase the supply of sand to a gravel- and cobble-bedded rivers. From hydrodynamics point of view, if …
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The Exchange of Fine Muddy Sediment in Gravel-Bed Fluvial Systems
… treated as being transported once the surface gravel layer that stores it is able to be mobilized. We propose that the surface layer need not be mobilized in order for muddy sediment to travel through the fluvial system in a series of erosive and depositional events. Our first study uses a new …
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Flow, sediment transport, and bed topography in straight and curved gravel-bed channels
… boundary shear stress variations in curved gravel bed channels. The flume experiments involved detailed measurements of bed topography, velocity, and sediment transport in both a curved channel and straight channel with and without an upstream obstruction. It was expected that the gravel bed …
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Temporal and Spatial Variation of Fine Sediment Infiltration in a Gravel-Bed River
Pulses of fine sediment in gravel-bedded rivers can cause extensive fine sediment infiltration (FSI), potentially altering river morphodynamics and aquatic ecosystems. FSI occurs when sand and silt are deposited into void spaces between larger grains at the riverbed. Flume and theoretical modeling …
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Temporal and Spatial Variation of Fine Sediment Infiltration in a Gravel-Bed River
Pulses of fine sediment in gravel-bedded rivers can cause extensive fine sediment infiltration (FSI), potentially altering river morphodynamics and aquatic ecosystems. FSI occurs when sand and silt are deposited into void spaces between larger grains at the riverbed. Flume and theoretical modeling …
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Field Use Of An Acoustic Surrogate System To Monitor Gravel Bed Load Flux
… and surrogate methods. Physical methods include bed load traps that provide data over a specific time frame, but the fluctuation of sediment can change drastically over hours; thus, bed load traps are unable to provide a reliable predictive model. Since studies have shown a relationship between …
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Legal Perspectives on Channel Migration of Wandering Gravel-Bed Rivers in Southern Alberta
… A behavioural model developed here for wandering gravel-bed rivers in southern Alberta indicates that change to these rivers is largely episodic and is mainly due to non-overbank peak seasonal flows rather than floods, but that rapid change can occur in response to certain events. Application of …
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Experimental studies of heavy-mineral transportation, segregation, and deposition in gravel-bed streams
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1986.
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Bedload Transport in Gravel-Bed Streams under a wide range of Shields Stresses
Bedload transport is a complicated phenomenon in gravel-bed streams. Several factors account for this complication, including the different hydrologic regime under which different stream types operate and the wide range of particle sizes of channel bed material. Based on the hydrologic regime, …
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Drivers of Spatial Dispersion and Residence Time of Coarse Sediment in Gravel-Bed Rivers
Transport of coarse sediment in gravel-bed streams alternates between mobile and immobile phases. Mobilized sediment disperses primarily in the streamwise and vertical directions. While travel times of sediment in the channel are brief, rest times between periods of mobilization can be relatively …
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Riparian Seedling Establishment Defined by Sediment Mobilization and Water Availability In a Gravel Bed River
Stream hydrograph and morphology are the main drivers of riparian white alder distribution. White alder seeds are preferentially deposited on stream bars where stream morphology and flow result in eddies. This thesis predicts the establishment success of riparian seedlings as a function of root …
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Multi-Scale detection, mapping, and modelling geomorphic change in gravel-bed rivers with UAV remote sensing
… are produced for a 2km reach of quasi-wandering gravel-bed river. Comparative analyses of DEMs between 2016 and 2018 reveals widening of the incised margin and significant geomorphic evolution characteristic of re-naturalization following the termination of gravel mining, channelization, and …
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Spatial patterns and drivers of floodplain change in the Squamish River, a dynamic gravel bed river
Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2024-03-01 without embargo terms
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Particle Size Distribution Analysis of a Mining-Impacted Gravel-Bed Stream in Ohio Using a Hybrid Sediment Sampling Technique
… the water column, and excessively silted streambeds. The current work presents the results of the particle size analyses performed on the hybrid samples in the context of evaluating the effectiveness of the technique itself and as a tool in future watershed/ecological studies, as well as …
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The Role of Geomorphic Features and Hydrologic Processes on Sediment Clusters in Gravel-Bed Rivers, Washington: A Field-Based Approach
… be an important characteristic of the variable bed topography of gravel-bed rivers. Detailed field descriptions and digital photographs of clusters were used to determine the characteristics of clusters at chosen locations on gravel bars regularly covered by high flow events. Data were collected …
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