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Results from computational morphodynamics modeling of coupled flow-bed-sediment systems are described for 10 applications as a review of recent advances in the field. Each of these applications is drawn from solvers included in the publicdomain International River Interface Cooperative (iRIC) software package. For mesoscale river features such as bars, predictions of alternate and higher mode river bars are shown for flows with equilibrium sediment supply and for a single case of oversupplied sediment. For microscale bed features such as bedforms, computational results are shown for the development and evolution of two-dimensional bedforms using a simple closure-based two-dimensional model, for two-and three-dimensional ripples and dunes using a three-dimensional large-eddy simulation flow model coupled to a physics-based particle transport model, and for the development of bed streaks using a three-dimensional unsteady Reynolds-averaged Navier-Stokes solver with a simple sedimenttransport treatment. Finally, macroscale or channel evolution treatments are used to examine the temporal development of meandering channels, a failure model for cantilevered banks, the effect of bank vegetation on channel width, the development of channel networks in tidal systems, and the evolution of bedrock channels. In all examples, computational morphodynamics results from iRIC solvers compare well to observations of natural bed morphology. For each of the three scales investigated here, brief suggestions for future work and potential research directions are offered.

Previous studies have demonstrated that riparian vegetation leads to channel transformation from a multi‐bar to a single‐thread channel planform. However, it still remains unclear how the presence of pioneer and mature vegetation affects the morphodynamics of single‐thread meandering rivers. In this study, we therefore investigated the effects of vegetation strength on the morphodynamic evolution of an experimental meandering channel. Three physical laboratory experiments were conducted using alfalfa sprouts in different life stages – no vegetation, immature vegetation, and mature vegetation – to simulate different floodplain vegetation strengths. Our results demonstrate that vegetation plays a key role in mediating bank erosion and point‐bar accretion, and that this is reflected in both the evolution of the channel bed as well as the sediment flux. The presence of mature vegetation maintained a deep, single‐thread channel by reducing bank erosion, thereby limiting both channel widening and sediment storage capacity. Conversely, an unvegetated floodplain led to channel widening and high sediment storage capacity. Channel evolution in the unvegetated scenario showed that the active sediment supply from outer bank erosion led to slightly delayed point‐bar accretion on the inner banks due to helical flow, deflecting the surface flow toward the outer banks and causing further erosion. In contrast, in the immature vegetation scenario, the outer banks were also initially eroded, but point‐bar accretion did not clearly progress. This led to a greater width‐to‐depth ratio, resulting in a transition from a single‐ to a multi‐thread channel with minor flow paths on the floodplain. The experimental results suggest that the eco‐morphodynamic effects of young (low‐strength) and mature (high‐strength) vegetation are different. Notably, low‐strength, early‐stage vegetation increases channel complexity by accelerating both channel widening and branching, and therefore might promote the coexistence of multi‐bars and pioneer vegetation.

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