The sahel (desert fringe) (case study) Flashcards
Where is the sahel?
The sahel is in a line crossing the middle of Africa, located along the south of the Sahara desert
What is desertification?
The process of semi-arid grassland becoming degraded and drier, turning into a desert
How many people are living in areas at risk of desertification?
1 billion
Why has the population in semi-arid areas grown?
- Natural increase as economies and standards of living improve in semi-arid areas.
- Migration as people escape conflicts; such as 3 million people in the Darfur region of Sudan.
What has happened to the Sahel over the past 50 years?
Less rainfall means less grazing and crop production as well as stopping underground water reserves from recharging. The lack of precipitation has caused the Sahel to slowly become a desert.
What are the reasons for desertification in the Sahel?
- Deforestation
- Poor farming practices
- Climate change
- Population growth
Where does most of the domestic energy come from in the Sahel?
80% of domestic energy comes from burning firewood.
What is happening to the demand for energy in the Sahel?
As population increases, the demand for energy increases.
What do people do to get firewood?
- They cut down every tree they can find.
- They strip the branches and leaves off the trees.
Why is Deforestation causing desertification in the Sahel?
- When there are less leaves to provide shade, the soil dries out quicker.
- Roots don’t hold the soil together anymore, causing soil erosion as the top layer of soil blows away or is washed away when it rains.
- Less leaves fall to the ground so there is less nutrients returned to the soil, making the soil less fertile.
Why is population growth causing desertification in the Sahel?
- The new people need resources to build houses.
What are the poor farming practices?
- Overgrazing
- Overcultivation
- Monoculture
- Poor irrigation systems
What is overgrazing?
- Overgrazing occurs when a farmer allows animals to graze on one site for too long.
Why does overgrazing cause desertification and what animals are the worst?
- They strip the vegetation so that there is nothing left to hold the soil together, causing the soil to blow away.
- The animals trample the land, leading to erosion.
- Goats and cattle are the worst
What is overcultivation?
- Population growth puts more pressure on agricultural land to produce more food.
- This more intensive use of the land takes away the nutrients from the soil.
- Water stores are drained as more crops need to be watered.
Why is overcultivation bad?
The countries have less crops to export, making them earn less money
What is Monoculture?
Planting one crop
Why is Monoculture bad?
Planting only one crop causes a lack of nutrients in the soil, causing the soil to become infertile
Why are poor irrigation systems bad?
- Poor irrigation systems lead to unsustainable use of water as lots of water is lost through evaporation, causing a buildup of salt crusts.
- Leads to over-abstraction of water sources, causing rivers and lakes to dry up.
Which countries are in the Sahel?
- Mauritiana
- Senegal
- The Gambia
- Guinea Bissau
- Mali
- Burkina Faso
- Niger
- Chad
- Sudan
- Eritrea
What is the most significant cause of desertification?
Climate change
What is cyclical drought?
A drought that occurs in cycles over a particular region. This means they are predictable but can still have impacts on agriculture, water supplies, ecosystems, and economies.
How do you reduce the risk of desertification?
- Water management
- Soil management
- Tree planting
- Use of appropriate technology
Water management
Drip irrigation is used to manage water supplies, ensuring that crops survive and soils don’t crack
