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Date	November 2017	Marks available	4	Reference code	17N.1.SL.TZ0.3
Level	Standard Level	Paper	Paper 1	Time zone	Time zone 0
Command term	Explain	Question number	3	Adapted from	N/A

Question

Figure 6(a): Map showing distribution of birch forest in 874 and in 2015

[Source: Map drawn by Björn Traustason, Icelandic Forest Service (www.skogur.is). Used with permission.]

Figure 6(b): Map showing soil erosion in Iceland in 2007

Figure 6(c): Model to show changes in vegetation cover during the six stages of soil degradation in Iceland

Figure 7(b): Known distribution of lupin in 2010

The resource booklet provides information on Iceland. Use the resource booklet and your own studies to answer the following.

Figure 7(a): Fact file on Nootka lupin

Native to North America.
Introduced in Iceland to stop soil erosion in 1885.
Invasive – spread quickly and outcompetes native flora.
Ministry of Environment recommended eradication of the lupin in highlands (above 400 m), national parks and conservation areas.
Removal methods include: grazing, use of herbicides, pulling up by hand, mowing.
Public participation encouraged to help with removal of the lupin.

[Source: Icelandic Institute of Natural History]

With reference to Figures 6(a), 6(b), 6(c) and 7(b) identify two ways in which vegetation cover has changed over time in Iceland.

[2]

Outline two ways in which human activity may have increased soil erosion in Iceland.

[2]

With reference to Figures 6(c), 7(a) and 7(b) explain the problems associated with land restoration in Iceland.

[4]

Markscheme

This question requires “Resource Booklet - Nov 2017 SL paper 1”, available under the "your tests" tab > supplemental materials.

vegetation cover has been significantly reduced;
change from woodlands to heath/moor/shrubs/desertified/bare landscape;
extent of birch forest has reduced (significantly/by more than half);
increase in coverage of lupins;
lupins replace/outcompete native flora;

Do not accept change from ‘vegetation cover to desertified landscape’

This question requires “Resource Booklet - Nov 2017 SL paper 1”, available under the "your tests" tab > supplemental materials.

deforestation has exposed the soil to erosion/made soil more prone to erosion/resulted in loss of root system that holds the soil in place;
overgrazing by livestock has prevented regeneration of vegetation/exposed soil to erosion;
climate change/global warming/higher temperatures has led to melting of ice and increased floods causing soil erosion;
trampling on ground can reduce vegetation and expose soil to erosion/cause soil particles to break away and increase erosion/cause soil compaction that increases runoff and associated soil erosion;

NB Only credit if reason given is explained, do not accept only "logging/deforestation/overgrazing/trampling/soil becoming compact/climate change/global warming" without an account of how this impacts erosion.
Accept other reasonable responses.

This question requires “Resource Booklet - Nov 2017 SL paper 1”, available under the "your tests" tab > supplemental materials.

can be expensive/labour intensive/the longer you leave it the more it costs;
the longer you leave it the lower your chance of success/chance of success is lowered with time/greater stage of vegetation loss;
strategies may have unforeseen/unpredicted effects;
eg lupins (introduced to control soil erosion) are invasive/outcompeting native species/have become a large-scale problem/have spread across the island;
eg herbicides may cause water pollution/adversely affect other species;
eg mowing/grazing/pulling up lupins can increase soil erosion;
harsh climate may make it difficult;
cause of problem may be external/global eg climate change;
reduction/low in soil nutrients/poor soils;

Accept other reasonable responses.

Level of success must be linked to time period/stage of vegetation loss to be credited the mark. Do not accept removal of lupins increases cost of restoration.

Examiners report

Although there were some very good answers, a significant number of candidates discussed the reasons for lack of vegetation and soil erosion levels rather than focusing on the actual change in vegetation cover.

Few candidates answered this question well. Some responses confused soil erosion with soil degradation. Many answers were too vague and just stated ‘farming’ or ‘grazing’ without explaining how these activities increases soil erosion.

Most candidates achieved some marks for this question by identifying the introduction of lupin, an invasive species as a key problem. Candidates that were also able to interpret the data in figure 6c appropriately achieved full marks.

Syllabus sections

Topic 7: Climate change and energy production » 7.2 Climate change—causes and impacts

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Topic 1: Foundations of environmental systems and societies » 1.5 Humans and pollution

Topic 1: Foundations of environmental systems and societies

Topic 4: Water and aquatic food production systems and societies

Topic 5: Soil systems and terrestrial food production systems and societies

Topic 7: Climate change and energy production

Question

Markscheme

Examiners report

Syllabus sections

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