12.3.2. Meanders
The continued action of the secondary flow developed around river bends causes further erosion and deposition of the sediment, respectively, on the concave and convex banks of the river. Thus, the river bends become more sharp and the river attains a meander pattern and becomes a meandering river. Meander patterns are usually associated with wide flood plains comprising easily erodible material.
There have been several attempts to explain the mechanism of meander development. According to Inglis (2), “Meandering is nature’s way of damping out excess energy during a wide range of varying flow conditions, the pattern depending on the grade of material, the relation between discharge and charge (sediment load), and the rates of change of discharge and charge”. Thus, a channel having excess energy attempts to increase its length by meandering thereby decreasing its slope.
Concave bank
Concave bank Convex bank
Convex bank
Bottom current
Surface/mid-depth current
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