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Title:
Nonlinear theoretical analysis of river meander dynamics with co-evolving riparian vegetation |
Abstract:
The present work revisits the classical bend theory intending to understand whether and how co-evolving riparian vegetation can affect the process of river bend stability and then initiates meander planform evolution. Classical bend theory treats vegetation’s influence as a simple modification to bank erosion resistance coefficient, E, which is usually assumed to be constant over space and time. This assumption may be inapplicable when the riparian vegetation is fast-growing and co-evolving following river channel mitigation. This paper proposes a new vegetation-influenced bank erosion model by linking erodibility with vegetation density, coupled with the classical bend theory model. For river meanders with small amplitudes, perturbation analysis is carried out to stabilize planform dynamics of meandering rivers, and the influence of the co-evolving riparian vegetation is discussed. Theoretical analysis shows that the most unstable wavelength, skewness, and fatness of river meanders are dominated by the ratio between vegetation growth rate and river migration rate.
Keywords: river meandering, riparian vegetation, bank erosion model, perturbation analysis
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Biography:
Dong Xu is professor in Hohai University, China. He got Phd. in Tianjin University, China in 2008 and worked as a faculty from 2008 to 2023 in Tianjin University. He has been a Marie Curie Fellow under the Seventh Framework Program of the European Union and worked as research fellow in Queen Mary, University of London, United Kingdom. He is now a professor in College of Water Conservancy and Hydropower Engineering, Hohai University, China. He is also a member of Key Laboratory of Hydrologic-Cycle and Hydrodynamic-System of Ministry of Water Resources of China. His research interests involves sediment transport in river and coastal environment and fluvial morphology.
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