O-LevelGeographyThe natural environment2217/12 · Oct/Nov 2020 · Q325 Marks

Study Fig. 3.1, which shows information about flows through a drainage basin. [Figure 3.1]

(a)(i)What is meant by transpiration?[1]
(a)(ii)Explain why the amount of interception varies: from place to place at different times of the year.[2]
(a)(iii)Identify the processes which take place at X, Y and Z in Fig. 3.1. X Y Z[3]
(a)(iv)Cawston Creek is a small river in Canada. On the outline map, Fig. 3.2 below, mark with arrows and label the following: a source (label S) a confluence (label C) a tributary which is less than 1 km long (label T) the watershed (label W) [Figure 3.2][4]
(b)(i)Study Figs. 3.3 and 3.4 (Insert), which are photographs showing two different rivers and their valleys. Describe the similarities and differences between the rivers shown in Figs. 3.3 and 3.4.[3]
(b)(ii)Explain how rivers erode their valleys.[5]
(c)Draw a labelled diagram to show the features of a river delta. Explain how a river delta is formed.[7]

This question uses a diagram from the original paper, which isn't shown here. Open the full paper from the past papers archive to see it.

Mark scheme

Marking points from the official mark scheme (Oct/Nov 2020). The mark or mark type is shown in brackets.

[1] The changing of water to water vapour by plants/evaporation of water by plants/trees.
[2] From place to place – different amounts/types of plants/vegetation/trees (or examples)
Different times of year – many plants/vegetation/trees will not have leaves all year/plants/vegetation/trees may grow only during certain seasons
2 @ 1 mark
[3] X = Overland flow/surface run off
Y = Throughflow
Z = Ground(water) flow/base flow
3 @ 1 mark
[4] On outline map.
4 @ 1 mark
Note: Multiple examples can only be credited if all are correct
[3] Similarities - both;
are narrow/thin/small;
have rocks (in channel);
flow in a valley;
shallow, etc.
Differences:
3.3/1st one has a waterfall/steeper long profile but 3.4 does not;
the long profile of 3.4/2nd one is more regular, etc.
3.3 has more turbulent water/white water;
Note:
1 MAX 2 on each of similarities/differences
2 Comparison is needed in the difference section – do not accept 'one is.one isn't' approach.
Features of the valley
Vegetation
Meanders/more winding
Speed of flow
Near source/in upper course
Similar width/size
3 @ 1 mark = 0
[5] Ideas such as:
Hydraulic action;
Pressure of water/air pressurized in cracks;
Corrasion/abrasion;
Sandpaper action of rocks carried by water on bed/banks;
Corrosion/solution;
Rocks dissolved by water/chemical action of water on rocks;
Attrition;
Rocks carried by water (reduced in size) as they hit each other
5@1 mark or development
Note: Only allow definitions of processes as stand alone points or correct development. Do not credit if definitions are linked with wrong names of processes.
e.g. Hydraulic action is pressure of water/air pressurized in cracks = 2 marks
Hydraulic action is sandpaper action of rocks carried by water on bed/banks = 1 mark
[7] Levels marking
Level 1 (1-3 marks): Statements including limited detail which explain how a delta is formed and/or labelling of features on diagram.
Level 2 (4-6 marks): More developed or linked statements which explain how a delta is formed
Level 3 (7 marks): Comprehensive and accurate answer using appropriate terminology, which explains how a delta is formed and labels of features on diagram.
Content Guide: Diagram is likely to include labelling of distributaries, shape of delta, flat land, sea, fertile soil, etc.
Explanation: Erosion of materials from upstream; Transportation of load; Reduction in speed of flow, Excess of sediment load cannot be carried further, Deposition, Flocculation, Lack of tides to remove materials, Colonisation by vegetation, etc.