Theory question 305
Rivers and River Landforms(a) With the aid of annotated diagrams, describe the characteristics of the various stages of a river course. (b) List three ways by which rivers are beneficial.
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(a) Upper (youthful) course: steep gradient; fast flow; vertical erosion; narrow V-shaped valley; interlocking spurs, waterfalls, rapids, potholes, gorges; small volume.
Middle (mature) course: gentler gradient; lateral erosion widens valley; larger volume; meanders begin; river cliffs and slip-off slopes; small floodplain.
Lower (old) course: very gentle gradient; slow flow; deposition dominant; wide floodplain; large meanders, ox-bow lakes, levees, braided channels; delta or estuary at the mouth.
Annotated diagrams: long profile and a cross-section for each stage.
(b) Water supply for domestic use and industries; irrigation; fishing; transport; HEP; fertile alluvial soils; tourism and recreation; sand and gravel for building; boundaries.
Annotate each diagram.