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Date May 2016 Marks available 10 Reference code 16M.2.bp.1
Level SL and HL Paper 2 Time zone
Command term Examine Question number 1 Adapted from N/A

Question

The map shows the Clutha River and the town Balclutha on the South Island of New Zealand. The scale of the map is 1:50 000 and the contour interval is 100 metres.

Identify and locate two natural river landforms found on the Clutha River’s floodplain.

[4]
a.

(i) Briefly explain how one human modification of the floodplain shown in area A (outlined in black) may reduce river flooding.
 

(ii) Suggest two ways in which the settlement of Balclutha may have led to increased river flooding.

[6]
b.

Examine how the environmental impacts of agriculture and irrigation on water quality vary from place to place.

[10]
c.

Markscheme

Award [1] for naming each feature eg meander, braiding, marshland, slip-off slope, river cliff, oxbow lake, distributary, eyot/ait/island, levee.

Award [1] for either a four-figure grid square reference or a valid locational/situational statement for each.

For example:
There is a meander [1] southeast of Stirling [1].
There is oxbow lake [1] at 4971 [1].

a.

(i)

Award [1] for identifying a modification and [1] for explanation.

For example:
Stopbank/artificial levee/embankment [1] allows higher
discharge/flow/increased capacity [1].
Drainage ditches/canals [1] carry water off the floodplain [1].
River deviation scheme [1] diverts water away from the main channel [1].

(ii)

Award [1] for each valid suggestion and [1] for why it may have led to increased flooding.

For example:
Road bridge over the river [1] constricts river flow and allows ponding/overflow of water [1].
Urban growth of Balclutha increases concrete/asphalt [1] which is impermeable so water runs into river [1].

b.

Responses should show an understanding of a variety of impacts (from agriculture and irrigation) on water quality eg, eutrophication, salinization, agro-chemical run-off, groundwater pollution.

It would be expected that the causes and environmental consequences of at least two impacts should be explained.

Variation/scale/place-to-place should be considered.

Good candidates may consider, for example, that eutrophication is widespread wherever there is arable or pastoral farming with unregulated run-off into water courses and it is found worldwide. May affect rivers, lakes, wetlands and coastal margins.

At band D, answers are likely to be mainly descriptive and/or look only at one impact.

At band E, expect either a more detailed explanation of a range of impacts or an examination of how different places are affected in varying ways.

At band F expect both.

Marks should be allocated according to the markbands.

c.

Examiners report

Most were able to identify two river landforms; meanders and ox-bow lake were the most common. There was a surprising inability to give a correct grid reference, or other location factor (although this was improved compared with previous sessions).

a.

(i) No problems; most chose artificial levee/stopbank.

(ii) Few problems; most referred to impermeable surfaces and increased run-off.

b.

Candidates showed understanding of a variety of impacts, such as eutrophication and salinization and their consequences, using located examples.

c.

Syllabus sections

Optional themes » Option A: Freshwater—issues and conflicts » Management issues and strategies » Irrigation and agriculture

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