Abstract
We modify a simple numerical stream-pattern model to examine the effect of sediment stabilization by roots on the channel pattern of bedload rivers. In the model, vegetation enhances bank resistance to erosion, causing the development of a single channel instead of a rapidly changing, multiple channel (braided) pattern. Net aggradation resulting from a high sediment supply, however, causes frequent avulsions that destroy vegetation locally, leading to the development of a multiple-channel pattern. A stability diagram representing multiple model runs predicts whether a river will exhibit single or multiple channels, based on plant-enhanced bank strength, and on the time scale of plant development relative to a time scale for change in unvegetated channels. A second stability diagram predicts the way in which the amplitude and period of a fluctuating imposed sediment load influence whether a single or multiple-channel pattern develops.
Original language | English (US) |
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Pages (from-to) | 131-143 |
Number of pages | 13 |
Journal | Earth Surface Processes and Landforms |
Volume | 28 |
Issue number | 2 |
DOIs | |
State | Published - Feb 2003 |
Keywords
- Bank stability
- Braiding
- Numerical modelling
- Single-channel
- Vegetation