River Bar Downscaling with Bed Sills and Bottom Groynes: A Numerical Study

Adaptation of river channels to a wetter or drier climate: Insights from the Lower Pilcomayo River, South America

Climate change has a direct influence on both hydrology and floodplain vegetation of water courses, which are key players in river morphodynamics. The river system response to climate change is complex and the effects of non-linear interactions between alterations in water, sediment and vegetation remain incompletely understood. Which of...

Morphological Adaptation of River Channels to Vegetation Establishment: A Laboratory Study

While the scientific community has long recognized that alluvial rivers are the product of interactions between flowing water and bed material transport, it is increasingly evident that vegetation mediates these interactions and influences the stream channel characteristics. In a novel set of mobile bed laboratory experiments with variable...

Impact of flow variability and sediment characteristics on channel width evolution in laboratory streams

Alluvial rivers are shaped by sequences of water flows excavating their channels. Observations show that besides the magnitude, the frequency and duration of streamflow oscillations might also be important for the river channel formation. In addition, the river morphology appears influenced by both size and degree of uniformity of the...

Effects of riparian and floodplain vegetation on river patterns and flow dynamics

Flume experiments and field observations demonstrating the effects of vegetation on river planforms are reported in literature, but numerical studies of these effects at the river scale are lacking. We investigated the effects of vegetation in a 2D morphodynamic model using submodels for flow resistance and colonisation of newly formed deposits....

Bank retreat study of a meandering river reach case study: River Irwell

Lack of data is often considered a limitation when undertaking morphological studies. This research deals with morphological studies of small rivers experiencing bank erosion processes when only limited data are available. A reach of the meandering gravel-bed river Irwell (United Kingdom) is taken as a case study in order to analyze the bank...

Intrinsic steady alternate bars in alluvial channels. Part 1: Experimental observations and numerical tests.

Alternate bars in straight alluvial channels are migrating or steady. The currently accepted view is that they are steady only if the width-to-depth ratio is at the value of resonance or if the bars are forced by a steady local perturbation. Experimental observations, however, seem to indicate that steady bars are also present in cases of...

Effects of smoothing and regridding in numerical meander migration models

Meander migration models include an as yet poorly investigated source of numerical errors related to the computation of the channel curvature, which are amplified by the procedure of adding and deleting grid points as the river planform evolves. The methods adopted to reduce these errors may influence size, form, and migration rate of the...