(a) Study Fig. 6, a diagram which shows how the load of a river is transported. [Figure 6.0 (Diagram illustrating different methods of river load transport: solution, X (suspension), Y (saltation), traction, with descriptions for each method)] Fig. 6 (b) Study Photograph C (Insert) which shows a waterfall. (c) For a named river you have studied, explain what has been done to reduce flooding. Name of river ..........................................................................................................................

Mark scheme

Marking points from the official mark scheme (May/June 2011). The mark or mark type is shown in brackets.

1. [1] (a) (i) Material which it is carrying
2. [2] (a) (ii) X. Suspension; Y. Saltation
3. [3] (a) (iii) Ideas such as: more load will be carried; heavier materials will be moved/large boulders may be moved; greater amount of traction will occur; materials usually moved by traction may be moved by saltation; more material in suspension; etc.
4. [4] (a) (iv) Areas such as: inner bend of meander/slip off slope/convex bank of meander; lower course/mouth; flood plain; levees; delta etc.; Reasons as appropriate such as: speed of flow reduces; load carried is too heavy for river; still water; flocculation/salt water makes them sink etc.; 2 Marks for area and 2 for reasoning; No double credit on reasons
5. [3] (b) (i) Features such as: vertical/steep drop/falls/cliff; long drop/10–15metres high; layers of rock/sedimentary rocks/bedding planes/stepped profile; plunge pool; broken rocks at edge; falls are wide/10–15 metres wide; white water/fast flowing/powerful; undercut/cave behind; overhang; etc.
6. [5] (b) (ii) Explanation of how a waterfall is formed which may include ideas such as: river flows across band of resistant/hard rock; underlain by softer rock; softer rock is eroded by hydraulic action/hard rock takes longer to erode; undercut/hard rock becomes unsupported; overhang collapses; plunge pool forms/deepens due to pressure of falling water; gorge formation/headward erosion/retreats; faulting/geological fault; etc.; NB Credit points made either on labelled diagrams or in written text
7. [7] (c) Levels marking; Level 1 (1-3 marks): Statements including limited detail describing what can be done to reduce flooding. (e.g. build higher banks, plant trees in drainage basin, build dams/reservoirs along course of river, straighten river etc.); Level 2 (4–6 marks): Uses named example. More developed statements describing what can be done to reduce flooding. (e.g. build higher banks so the river will have a greater capacity; raise banks especially in areas where river flows at a higher level than flood plain; plant trees so flow will not be so flashy/so less water will get to river as more evapo-transpiration occurs; build dams to regulate flow of water; straighten river so water is removed from drainage basin more quickly etc.); (NB MAX 5 marks if no named example); Level 3 (7 marks): Uses named example (e.g. River Mississippi). Comprehensive and accurate statements including some place specific reference. (e.g. built high levees so the river will have a greater capacity; raised banks protecting cities like Memphis where river flows at a higher level than flood plain; planting trees in Tennessee Valley so flow will not be so flashy/so less water will get to river as more evapo-transpiration occurs; much straightening of river/meanders cut off between New Orleans and Memphis etc.)