Coevolution of width and sinuosity in meandering rivers

2014 ◽  
Vol 760 ◽  
pp. 127-174 ◽  
Author(s):  
Esther C. Eke ◽  
M. J. Czapiga ◽  
E. Viparelli ◽  
Y. Shimizu ◽  
J. Imran ◽  
...  
Keyword(s):  
Erosion Rate ◽  
Bank Erosion ◽  
Channel Width ◽  
Channel Migration ◽  
Meandering Rivers ◽  
Local Curvature ◽  
Meandering River ◽  
Bed Elevation ◽  
Dependent Rate ◽  
Variation Patterns

AbstractThis research implements a recently proposed framework for meander migration, in order to explore the coevolution of planform and channel width in a freely meandering river. In the model described here, width evolution is coupled to channel migration through two submodels, one describing bank erosion and the other describing bank deposition. Bank erosion is modelled as erosion of purely non-cohesive bank material damped by natural armouring due to basal slump blocks, and bank deposition is modelled in terms of a flow-dependent rate of vegetal encroachment. While these two submodels are specified independently, the two banks interact through the medium of the intervening channel; the morphodynamics of which is described by a fully nonlinear depth-averaged morphodynamics model. Since both banks are allowed to migrate independently, channel width is free to vary locally as a result of differential bank migration. Through a series of numerical runs, we demonstrate coevolution of local curvature, width and streamwise slope as the channel migrates over time. The correlation between the local curvature, width and bed elevation is characterized, and the nature of this relationship is explored by varying the governing parameters. The results show that, by varying a parameter representing the ratio between a reference bank erosion rate and a reference bank deposition rate, the model is able to reproduce the broad range of river width–curvature correlations observed in nature. This research represents a step towards providing general metrics for predicting width variation patterns in river systems.

Numerical simulation of bank erosion and channel migration in meandering rivers

2002 ◽  
Vol 38 (9) ◽  
pp. 2-1-2-21 ◽  
Author(s):  
Stephen E. Darby ◽  
Andrei M. Alabyan ◽  
Marco J. Van de Wiel
Keyword(s):  
Numerical Simulation ◽  
Bank Erosion ◽  
Channel Migration ◽  
Meandering Rivers

Upstream and downstream morphodynamic influence in simulated and real meandering rivers

2021 ◽  
Author(s):  
Hossein amini ◽  
Guido Zolezzi ◽  
Federico Monegaglia ◽  
Emanuele Olivetti ◽  
Marco Tubino
Keyword(s):  
Migration Rate ◽  
Machine Learning Techniques ◽  
Stochastic Gradient Descent ◽  
Support Vector ◽  
Lateral Migration ◽  
Remotely Sensed Data ◽  
Meandering Rivers ◽  
Meandering River ◽  
Migration Rates ◽  
Meander Migration

<p>This study investigates the dependency of meander lateral migration rates on the spatial distribution of channel centerline curvature in both synthetic and real meandering rivers. It employs Machine Learning techniques (hereafter ML) to relate observed local lateral meander migration rates with the local and the upstream/downstream values of the centerline curvature. To achieve this goal, it was primarily essential to identify the feasibility of using ML in the meandering river's morphodynamics. We then determined the ability of ML to predict the excess near bank velocity based a set of input data using different regression techniques (linear and polynomial, Stochastic Gradient Descent, Multi-Layer Perceptron, and Support Vector Machine). We then moved forward to study the upstream-downstream influence on local migration rate. Synthetic meandering river planforms, as obtained through the planform evolution model of Bogoni et al. (2017), which is based on Zolezzi and Seminara (2001) meander flow model, were used as test cases for the calibration and check of the different adopted ML algorithms. The calibrated algorithms were then applied to multi-temporal information on meander planform dynamics obtained through the PyRiS software (Monegaglia et al., 2018), to quantify to which extent the upstream and downstream distribution of meander centerline curvature affects the local meander migration rate in real rivers.</p><p>References </p><p>1- Zolezzi, G., & Seminara, G. (2001b). Downstream and upstream influence in river meandering. Part 1. General theory and application overdeepening. Journal of Fluid Mechanics, 438(September 2015), 183–211. https://doi.org/10.1017/S002211200100427X</p><p>2- Monegaglia, F., Zolezzi, G., Güneralp, I., Henshaw, A. J., & Tubino, M. (2018). Automated extraction of meandering river morphodynamics from multitemporal remotely sensed data. In Environmental Modelling & Software (Vol. 105, pp. 171–186). https://doi.org/10.1016/j.envsoft.2018.03.028</p><p>3- Bogoni, M., Putti, M., & Lanzoni, S. (2017). Modeling meander morphodynamics over self-formed heterogeneous floodplains. In Water Resources Research (Vol. 53, Issue 6, pp. 5137–5157). https://doi.org/10.1002/2017wr020726</p><p>4- Benozzo, D.,  Olivetti, E., Avesani, P. (2017). Supervised Estimation of Granger-Based Causality between Time series. In Frontiers in Neuroinformatics. </p><p>https://doi.org/10.3389/fninf.2017.00068 </p><p>5- Sharma A., Kiciman, E. (2020). DoWhy: An End-to-End library for Causal Inference. arXiv preprint arXiv:2011.04216. </p><p>https://arxiv.org/abs/2011.04216</p>

scholarly journals Supplied Sediment Tracking for Bridge Collapse with Large-Scale Channel Migration

Water ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1881
Author(s):  
Takuya Inoue ◽  
Jagriti Mishra ◽  
Kazuo Kato ◽  
Tamaki Sumner ◽  
Yasuyuki Shimizu
Keyword(s):  
Erosion Rate ◽  
Large Scale ◽  
Bank Erosion ◽  
Strong Relationship ◽  
Sediment Supply ◽  
Study Region ◽  
Flow Discharge ◽  
Bridge Abutment ◽  
Bridge Collapse ◽  
Flooding Events

Here, we provide a numerical model that assigns an identification number to trace sediments and also identify the source of sediment supply. We analyze the efficacy of our model by reproducing the reach-scale field observations from flooding events in 2010 and 2016 that affected Kyusen Bridge over the Bebetsu River, Hokkaido, Japan. Our simulation results can successfully reproduce and trace the formation of bars caused by sediment supply in the study region. Our study also suggests a strong relationship between bank erosion rate, sediment supply and flow-discharge. The bank erosion rate is higher when sediment supply increases, and bank erosion reduces as flow discharge goes down. The model can also replicate the changes in a bed concerning sediment supply and was used to reproduce the bridge-abutment failure caused by the 2016 flooding with large sediment supply and the bridge-pier failure caused by the 2010 flooding with less sediment supply.

scholarly journals Numerical simulation of bedload tracer transport associated with sand bar formation, bank erosion, and channel migration

2018 ◽  
Vol 40 ◽  
pp. 02013
Author(s):  
Toshiki Iwasaki ◽  
Satomi Yamaguchi ◽  
Hiroki Yabe
Keyword(s):  
Numerical Model ◽  
Bank Erosion ◽  
Bedload Transport ◽  
Transport Processes ◽  
Tracer Transport ◽  
Channel Migration ◽  
River Systems ◽  
Sand Bars ◽  
Tracer Particles ◽  
Bar Formation

An understanding of bedload transport processes is an essential research goal for better prediction of river morphology and morphodynamics as well as the transport and fate of sediment-bound materials in river systems. Passive tracer particles have been used widely to monitor bedload transport processes in rivers by measuring the spatiotemporal distribution of the bedload tracers. Here, we propose a numerical model for reproducing the transport of bedload tracers in river systems, more specifically, the behaviours of bedload tracers under the influence of complex river morphodynamics. A two-dimensional morphodynamic model is combined with a flux-based bedload tracer model with use of the active layer approach. The model is applied to a laboratory experiment that demonstrates the transport processes within the channel of bedload tracers supplied from the floodplain. The numerical model effectively reproduces the main features of the experiment, namely, the bedload tracers supplied from the floodplain due to bank erosion deposit onto sand bars developed within the channel. Because the sand bars cause a very long residence time of the bedload tracers within the bed, the transport speed of the tracers is slowed significantly under the influence of bar formation and channel migration.

Analysis of channel bank erosion rate using exposed roots of trees: a case study of lavij stream, northern Alborz Mountains, Iran

2020 ◽  
Vol 17 (5) ◽  
pp. 1096-1105
Author(s):  
Mohammad Mehdi Hosseinzadeh ◽  
Saeedeh Matsh Beyranvand ◽  
Reza Esmaili
Keyword(s):  
Erosion Rate ◽  
Bank Erosion

Bank erosion and channel width change in a tropical catchment

2008 ◽  
Vol 33 (14) ◽  
pp. 2174-2200 ◽  
Author(s):  
Rebecca Bartley ◽  
Rex J. Keen ◽  
Aaron A. Hawdon ◽  
Peter B. Hairsine ◽  
Mark G. Disher ◽  
...  
Keyword(s):  
Bank Erosion ◽  
Channel Width ◽  
Width Change
Sign in / Sign up

Export Citation Format

Share Document