How Does Stream Erosion Shape Meandering Streams?
Where is stream erosion concentrated along a meandering stream?
1. On the outer bank of a meander bend
2. On the floodplain during times of low discharge
3. On the inner bank of a meander bend where a point bar forms
4. On the straight channel segment between meander bends
Answer:
Stream erosion is most concentrated on the outer bank of a meander bend. This is due to the corkscrewing flow of the water as it encounters the outer bank, runs along the riverbed, and deposits eroded material on the inner bank.
Meandering streams are dynamic systems that constantly shape and reshape their banks through erosion and deposition. The movement of water around a meander bend plays a crucial role in this process.
As water flows around a bend in a meandering stream, the outer bank experiences the most erosion. The water is forced to the outside of the curve, where it erodes the bank and carries away sediment. In contrast, the inner bank of the bend accumulates sediment as the water moves more slowly on this side.
Over time, the constant erosion on the outer bank and deposition on the inner bank cause the meander to change shape. The meander bends slowly migrate downstream as a result of this process.
Additionally, erosion is more effective on the downstream side of a meander due to the slope of the channel. This is why beaches and sandbars are often visible on the inside of the curve.
Overall, stream erosion plays a significant role in shaping meandering streams, constantly reshaping their banks and altering their course over time.