Please info on research questions and methods about such process. All I find is case studies in field. Incision is relevant as it is likely to become more frequent in mountain basins with non-stationary hydrological regime. Thanks!
Flume experiments are often installed to gauge streamflow with metered flume dimensions that affect elevation of flow in a controlled way. The installation of flume or weir is likely to affect incision/deposition as a modification of channel dimension, much like a levee might. The velocity through the flume is increased as the channel is constrained. Measuring incision can be done with varying methods including surveying cross sections, installing vertical buried channel chains such as at top of riffles, and documenting if chain is exposed or chain was exposed, moved horizontally to some depth and reburied with fresh gravels. If the bankfull flow and larger floods no longer have access to a floodplain, the channel is considered entrenched. Mining, clean water releases below dams, hydrologic modifications that constrain channel dimension can lead to entrenchment. Works by geomorphologists such as David Rosgen, Luna Leopold, Mathias Kondoff, and others could be reviewed for added ideas in methods. Field measuerments are probably best. But when I get to computer and my files, I think I may have a paper or two using flumes and measuring shear bank stress, velocity patterns, etc. if sediment and bedload sources are in balance with flow regime (esp. bankfull flow), the stream will likely maintain a fairly stable dimension. It is not uncommon for mountain streams to be entrenched, as floodprone area adjacent to channel is constrained by slop topography, and sometimes bedrock or boulders is the ultimate grade control. It is important to maintain large wood sources in mountain streams for habitat, grade control, gravel capture so step pool morphology can develop in fairly steep gradients. Historic efforts to remove coarse wood from stream channels were often a mistake relative to aquatic habitat and channel stability.
I thought this was a outstanding paper by Kean et al 2009 concerning the shear stresses and primary and secondary velocity profiles in a flume experiment. Note the stress jumps or depresses as flume configuration boundaries change. Hot velocity pockets noted also for secondary velocity.
I added one of the Kondolf papers on extraction of aggregate materials and its affect on incision, etc.
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