Name three physical causes of desertification.

Prolonged drought, high rainfall variability, and strong winds removing exposed soil.

Name four human causes of desertification.

Overgrazing, over-cultivation, deforestation for fuelwood, and over-abstraction of groundwater.

Explain how overgrazing leads to desertification.

Too many animals remove the vegetation faster than it regrows, so the soil is left bare, compacted by hooves and exposed to wind and rain.

Explain how over-cultivation degrades dryland soil.

Continuous cropping without fallow or fertiliser exhausts the nutrients and the organic matter that binds the soil, so structure collapses and it blows or washes away.

WJEC A-Level Geography 601-8455-3

Coastal Landscapes

Glaciated Landscapes

Topic overview The glacier as an open system Climate change and the glacier budget Glacier movement Types of ice mass and their distribution Glacial weathering and erosion processes Macro-scale erosional landforms Glacial transport and depositional landforms Fluvioglacial landforms Suites of landforms in glacial landscapes Periglacial processes and ground ice Periglacial action of water and wind Glacial change over different timescales Glacial environments and human activity

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Changing Places

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Water and Carbon Cycles

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Global Migration

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Global Governance of the Oceans

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EcosystemsContemporary theme

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Economic Growth and Challenge: IndiaContemporary theme

Topic overview India's relief, drainage and climate India's population, society and governance India's resources, hazards and economic geography India's global role and economic growth Environmental pressures of India's growth Sustainable development strategies in India

Economic Growth and Challenge: ChinaContemporary theme

Topic overview China's relief, drainage and climate China's population, society and governance China's resources, hazards and economic geography China's global role and economic growth Environmental pressures of China's growth Sustainable development strategies in China

Development in an African ContextContemporary theme

Topic overview Defining and measuring development Physical factors influencing development Economic factors influencing development Political, social and cultural factors in development The environmental cost of development Desertification Strategies to promote development

Energy Challenges and DilemmasContemporary theme

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Weather and ClimateContemporary theme

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Fieldwork and Geographical Skills

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Key Concepts in Geography

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Development in an African Context

Desertification

3 things to know
A2 Unit 4

Overview

Three physical causes of desertification, four human causes of desertification and how overgrazing leads to desertification.

What you need to know

Answer each one before you reveal it.

Your recallNot started

Key term

Explain the albedo feedback in desertification.

Key term

Define desertification.

Key term

Which region is most often cited as suffering severe desertification?

Questions from this subtopic

Each one with the model answer underneath.

1
Define desertification.
Model answer
Desertification is the degradation of land in arid, semi-arid and dry sub-humid areas to desert-like conditions.
2
Which region is most often cited as suffering severe desertification?
Model answer
The Sahel, the belt of semi-arid land along the southern margin of the Sahara.
3
Name three physical causes of desertification.
Model answer
Prolonged drought, high rainfall variability, and strong winds removing exposed soil.
4
Name four human causes of desertification.
Model answer
Overgrazing, over-cultivation, deforestation for fuelwood, and over-abstraction of groundwater.
5
Explain how overgrazing leads to desertification.
Model answer
Too many animals remove the vegetation faster than it regrows, so the soil is left bare, compacted by hooves and exposed to wind and rain.
6
Explain how over-cultivation degrades dryland soil.
Model answer
Continuous cropping without fallow or fertiliser exhausts the nutrients and the organic matter that binds the soil, so structure collapses and it blows or washes away.

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