Desertification

How much did the scheme cost?

2 billion dollars from the world bank

How does climate change cause desertification?

Climate gets hotter, less rainfall, less water supply, less vegetation grows, soil becomes bare and land is infertile so the land becomes a desert.

How do humans use the Sahel region?

Hunting, agriculture, tourism and deforestation.

Why is vegetation important?

Intercepts rain, shades soil prevents it getting too hot, moisture transpires which causes clouds and rain, acts as a wind break.

How do earth bunds reduce erosion by water flow?

It increases the water table meaning the soil is more moist leading to more local rainfall. This also traps the water preventing it removing the soil.

What is the great green wall?

It is a 9 mile band of trees which is 4,300 miles long and goes through 11 countries, including Chad, Niger, Mali and Sudan. It is designed to protect the Sahel region from desertification.

What is a holistic approach to managing hot deserts?

Land. Sustainable agriculture and natural resource management. Water. Water used efficiently. Social. Community awareness of the problems.

How does over cultivation cause desertification?

Nutrients are removed due to the continual use of the soil which exhausts the soil meaning nothing can grow there and he soil is left bare to wind erosion.

What causes desertification?

Over cultivation, overgrazing, deforestation, slash and burn, climate change.

What is coppicing? How does it help prevent erosion?

People are advised to harvest not remove the trees as the roots can still bind the soil together preventing wind erosion and the trees will grow back to enable a continual supply of materials.

Why does deforestation cause desertification?

People need the wood and so fewer trees mean that the ground is left open to wind and water erosion.

What are some of the positives for people?

Prevents dust, gives jobs, provides resources, water in the future, bring back animals, diverse vegetables, prevents spread of desert.

Why is the great green wall important?

Protects the land, allows soil to regenerate, allows resources to be used by locals, decreases dust in areas, aids the locals during the 10 month dry season.

How is the great green wall holistic?

Raising the social awareness and combating misuse of the ground and also preventing desertification and providing for the locals.

How can soil erosion be prevented from water flow?

Replanting trees, earth bunds, terracing, gully plugs.

What are the negatives?

Some areas are occupied by rebel groups and the people see the trees for short term gain.

What is desertification?

The spreading of deserts

How do wind breaks prevent soil erosion by wind?

They act as a physical barrier to prevent the wind damaging crops and it traps blown soil. The fertile land protected enables more vegetation to be grown supplying the people with resources.

How does overgrazing cause desertification?

Too many animals eat all the vegetation on the area leaving it bare to wind erosion.

How can soil erosion be prevented from wind erosion?

Wind breaks, crop rotation, grassland development, animal husbandry.