Theory question 207
Rivers and River Landforms(a) Describe the three stages of development of a river along its course. (b) Highlight two ways in which rivers are important to man.
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(a) Upper (youthful/torrent) course: steep gradient near the source; fast flow; vertical erosion dominates; narrow V-shaped valleys, gorges, waterfalls, rapids, potholes, interlocking spurs.
Middle (mature/valley) course: gentler gradient; lateral erosion widens the valley; load carried in suspension and solution; meanders begin; some deposition on valley floor.
Lower (old/plain) course: very gentle gradient; slow flow; deposition dominates; wide flood plain, meanders, ox-bow lakes, levées, braided channels, deltas or estuaries.
(b) Water for domestic, industrial and irrigation use; HEP; transport; fishing; fertile alluvial soils; recreation and tourism; boundaries; alluvial minerals (gold, diamond, tin).
For each stage say gradient, main process and landforms.