GCSE Geography Quiz - Desertification (Questions)

One of the topics looked at in GCSE Geography is the degradation of dryland - also know as desertification. This quiz looks at the causes of, and some possible solutions to, desertification.

Desertification is the persistent degradation of dryland ecosystems caused by variations in climate and human activities. Drylands occupy nearly half the planet's land area, and in 2000 were home to around one-third of the Earth’s population.

Drylands are, as the name suggests, areas where water is scarce. In the past, nomadic lifestyles and low levels of agriculture meant that the risk of over cultivation was relatively low. But the marginal conditions in drylands mean that climate change and human pressures can easily tip the balance and destroy their fragile ecosystems, leaving nothing but bare soils behind. Up to 20% of the world’s drylands have already been degraded, but the facts are that these changes are affecting the world’s poorest populations.

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That these populations are the poorest, means that they rely on the local ecosystem more than the inhabitants of developed nations. Food, fuel, construction materials, grazing for livestock - all come from the local environment. As the climate fluctuates the desert expands, forcing people to cultivate further marginal land and leading to more land degradation.

A great case study to learn for use in essays and exams is that of the Masai tribes of the Kenyan Serengeti. Originally nomadic farmers, their traditional system of moving from one area to another allowed the land to recover, before commercial farmers moved in to convert the premium lands to commercial agriculture. When the Serengeti National Park was created the Masai and their herds were excluded. These two factors, along with expanding populations, forced the Masai on to marginal lands. Private ownership of land now limits the Masai’s ability to move, and so leads to overgrazing on these marginal lands. This overgrazing has led to desertification.

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1. In areas under threat from desertification, people are forced to use marginal lands. How are these marginal lands defined?
[ ] Lands along the edges of a desert or a lake
[ ] Lands that form the boundary between two tribal areas. Grazing here can lead to tribal conflict
[ ] Lands that have little or no potential for profit. They often have poor soils or other undesirable characteristics
[ ] Lands that are at the edges of cities and may be heavily contaminated
2. Which of the following is a human cause of desertification?
[ ] Increased flock and herd size
[ ] Seasonal rainfall being unreliable
[ ] Climate change
[ ] Certain crops going extinct
3. How can rainfall be made more reliable in areas under threat from desertification?
[ ] Better weather forecasting
[ ] Damming of rivers
[ ] Better crop selection
[ ] Cloud Seeding
4. Dams have been built on a number of major rivers to increase the amount of water available for drinking and agriculture. How can artificial irrigation increase desertification?
[ ] It causes rapid soil erosion
[ ] It causes salinisation of the soil
[ ] It causes soil contamination
[ ] It causes sheet erosion
5. Magic stones are a project in which piles of stones are placed across slopes. How do these help reduce desertification?
[ ] The stones prevent soil blowing away by holding it down
[ ] The stones slow surface water run-off and soil erosion
[ ] The stones stop goats and other grazing animals destroying the vegetation
[ ] The stones remind people that the soil needs to be protected
6. How can plant science help increase the amount of vegetation in areas and so slow, or even reverse desertification?
[ ] By developing or discovering more drought resistant versions of crops such as millet and cotton
[ ] By creating new crops from varieties such as algaes and cactus
[ ] By changing the ground in specific ways to suit the water-intensive crops that are required
[ ] By developing treatments and medicines to help the crops survive times when there is little water
7. Which of the following is not a way that planting trees will help reduce desertification?
[ ] By acting as a wind-break to reduce the amount of sand being blown away
[ ] By producing water as rainfall in the immediate area
[ ] By providing a source of sustainable fuel
[ ] By protecting the remaining soil and allowing a leaf litter layer to develop
8. Which of the following is a physical cause of desertification?
[ ] Overgrazing
[ ] Irrigation
[ ] Changing farming practices
[ ] Climate change
9. Which of the following is a disadvantage of afforestation?
[ ] Trees lock up carbon dioxide
[ ] Newly planted trees prevent other plants from getting water
[ ] Trees prevent windblown sand moving to form sand dunes
[ ] Trees become a source of firewood that will be used in stoves by local people
10. Which of the following is not a possible strategy to reduce desertification?
[ ] Havesting branches rather than complete trees for fire wood
[ ] Controlled burning of grasslands to reduce the spread of wildfires
[ ] Reducing the number of livestock animals
[ ] Developing national parks and reserves where local people aren't permitted
GCSE Geography Quiz - Desertification (Answers)
1. In areas under threat from desertification, people are forced to use marginal lands. How are these marginal lands defined?
[ ] Lands along the edges of a desert or a lake
[ ] Lands that form the boundary between two tribal areas. Grazing here can lead to tribal conflict
[x] Lands that have little or no potential for profit. They often have poor soils or other undesirable characteristics
[ ] Lands that are at the edges of cities and may be heavily contaminated
Lands that are considered marginal for crops may be suitable for animal grazing in some circumstances, or for different farming methods
2. Which of the following is a human cause of desertification?
[x] Increased flock and herd size
[ ] Seasonal rainfall being unreliable
[ ] Climate change
[ ] Certain crops going extinct
Whilst climate change is influenced by human activity, it is considered a natural cause of desertification rather than a human one
3. How can rainfall be made more reliable in areas under threat from desertification?
[ ] Better weather forecasting
[ ] Damming of rivers
[ ] Better crop selection
[x] Cloud Seeding
Some people believe that messing with the atmosphere in this high-tech way may have as yet unknown impacts
4. Dams have been built on a number of major rivers to increase the amount of water available for drinking and agriculture. How can artificial irrigation increase desertification?
[ ] It causes rapid soil erosion
[x] It causes salinisation of the soil
[ ] It causes soil contamination
[ ] It causes sheet erosion
Salinisation is an increase in levels of salt in the soil as minerals are drawn up to the surface by water evaporation
5. Magic stones are a project in which piles of stones are placed across slopes. How do these help reduce desertification?
[ ] The stones prevent soil blowing away by holding it down
[x] The stones slow surface water run-off and soil erosion
[ ] The stones stop goats and other grazing animals destroying the vegetation
[ ] The stones remind people that the soil needs to be protected
These piles of stones are laid across a slope and trap surface water runoff, so reducing soil erosion
6. How can plant science help increase the amount of vegetation in areas and so slow, or even reverse desertification?
[x] By developing or discovering more drought resistant versions of crops such as millet and cotton
[ ] By creating new crops from varieties such as algaes and cactus
[ ] By changing the ground in specific ways to suit the water-intensive crops that are required
[ ] By developing treatments and medicines to help the crops survive times when there is little water
Genetically modified crops can help in these situations, as can moving crops from a different area, such as moving early maturing millet from southern to northern Mali. Improving the soil using fertilisers such as animal dung also helps
7. Which of the following is not a way that planting trees will help reduce desertification?
[ ] By acting as a wind-break to reduce the amount of sand being blown away
[x] By producing water as rainfall in the immediate area
[ ] By providing a source of sustainable fuel
[ ] By protecting the remaining soil and allowing a leaf litter layer to develop
Charity programmes, such as that of the Green Cross in Burkina Faso, educate local populations on the use of plant nurseries and fuel saving stoves
8. Which of the following is a physical cause of desertification?
[ ] Overgrazing
[ ] Irrigation
[ ] Changing farming practices
[x] Climate change
Climate change is a leading cause of desertification, along with unsustainable land usage
9. Which of the following is a disadvantage of afforestation?
[ ] Trees lock up carbon dioxide
[x] Newly planted trees prevent other plants from getting water
[ ] Trees prevent windblown sand moving to form sand dunes
[ ] Trees become a source of firewood that will be used in stoves by local people
The trees may die due to lack of water. It could be argued that funding could be better spent on more effective projects
10. Which of the following is not a possible strategy to reduce desertification?
[ ] Havesting branches rather than complete trees for fire wood
[ ] Controlled burning of grasslands to reduce the spread of wildfires
[ ] Reducing the number of livestock animals
[x] Developing national parks and reserves where local people aren't permitted
The creation of the Serengiti National Park has lead to the overgrazing of marginal lands