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Bank erosion is incorporated in onedimensional and twodimensional horizontal models for river morphology. The banks are assumed to consist of a fraction of cohesive material, which becomes washload after being eroded, and a fraction of granular material, with the same properties as the material of the bed. The banks are taken to be eroded by discharge flow causing lateral entrainment of lower parts of the banks and nearbank bed degradation, both inducing mass failure of upper parts of the banks. Theoretical analyses are performed in order to reveal the influence of bank erosion on the morphological system. From an analysis of characteristics of the onedimensional model it is concluded that generally river widths cannot be stabilized by protecting certain carefully chosen bank section~ only, and that computations of river planimetry can be decoupled from the computations of flow and bed topography. A linear analysis of the onedimensional model is used to clarify the interactions between bank and bed disturbances, whereas a linear analysis of the twodimensional model is used to demonstrate that the input of bank erosion products decreases transverse bed slopes, but hardly influences the wave lengths and damping lengths of flow and bed topography in natural rivers with moderately migrating banks.
ABSTRACT Bank erosion is incorporated in one-dimensional and two-dimensional horizontal models for river morphology The banks are assumed to consist of a fraction of cohesive material, which becomes washload after being eroded, and a fraction of granular material, with the same properties as the material of the bed The banks are taken to be eroded by discharge flow causing lateral entrainment of lower parts of the banks and near-bank bed degradation, both inducing mass failure of upper parts of the banks Theoretical analyses are performed in order to reveal the influence of bank erosion on the morphological system From an analysis of characteristics of the one-dimensional model it is concluded that generally river widths cannot be stabilized by protecting certain carefully chosen bank section~ only, and that computations of river planimetry can be decoupled from the computations of flow and bed topography A linear analysis of the one-dimensional model is used to clarify the interactions between bank and bed disturbances, whereas a linear analysis of the twodimensional model is used to demonstrate that the input of bank erosion products decreases transverse bed slopes, but hardly influences the wave lengths and damping lengths of flow and bed topography in natural rivers with moderately migrating banks ... ABSTRACT Bank erosion is incorporated in one-dimensional and two-dimensional horizontal models for river morphology The banks are assumed to consist of a fraction of cohesive material,... characteristics of the one-dimensional model it is concluded that generally river widths cannot be stabilized by protecting certain carefully chosen bank section~ only, and that computations of river planimetry... banks and near -bank bed degradation, both inducing mass failure of upper parts of the banks Theoretical analyses are performed in order to reveal the influence of bank erosion on the morphological