Desertification

Question 1

What is desertification?

Answer 1

The degradation of land, making it drier and less productive.

Question 2

Where is most at risk of desertification?

Answer 2

Desert margins

Question 3

How does desertification come about

Answer 3

When vegetation is removed. Exposed soil is easily removed by wind or water as there is no roots to hold it together. Nutrients in the soil are lost. The ground becomes sandy, dusty stony

Question 4

What are the causes of desertification?

Answer 4

Climate change
Population growth
Overgrazing
Over cultivation
Soil erosion

Question 5

Causes of desertification- climate change?

Answer 5

Temperatures - temperatures rising, higher temperatures cause more water to evaporate from the land. This makes soils drier, so plants struggle to grow

Rainfall - reducing rainfall means less water for plant growth, so more plants die

Question 6

Causes of desertification- population growth?

Answer 6

More people put more pressure on the land, leading to even more deforestation (e.g. for firewood) and overgrazing

Question 8

Causes of desertification- removal of fuel wood

Answer 8

Many people in dry areas rely on wood as food for cooking, removal of trees leaves soil exposed

Question 9

Causes of desertification - overgrazing

Answer 9

Too many cattle eat plants faster than they can re grow. Trampling animals also erodes the soil

Question 10

Causes of desertification- over cultivation

Answer 10

If crops are planted in the same area over and over again, all the nuitrents in the soil are used up , this means plants can no longer grow in these areas

Question 11

Causes of desertification - soil erosion

Answer 11

Wind and rain remove topsoil - nothing left to grow on

Question 12

What strategies can be used to reduce desertification risk?

Answer 12

Water and soil management

Tree planting

appropriate technology

Great green wall

Question 13

Reducing desertification risk water management?

Answer 13

Growing crops that need little water - reduce water use. Using drip irrigation on crops instead of surface irrigation means soil isn’t eroded by lots of water being added all at once

Question 14

Reducing desertification risk- soil management?

Answer 14

Leaving areas of land to rest between grazing or planting lets them recover there nutrients

Rotating crops that take different nutrients from the soil prevents nutrients from being continually removed.

Question 15

Reducing desertification risk - tree planting

Answer 15

Trees can be planted to act as wind breaks, reducing wind erosion, growing trees among crops protects them from the sun.

Question 16

Reducing desertification risk - appropriate technology?

Answer 16

Involves using cheap, sustainable and easily available materials to build things that are easy for local people to maintain. For example sand fences or terraces can be constructed to stabilise soil and reduce erosion.