U1: Sahel

• What is the definition of desertification?

  The process by which land becomes drier and degraded
• What are desert fringes?

  Semi-arid land on the edge of hot deserts
• What is the average yearly rainfall in the Sahel region?

  Roughly 170 mm
• Why is the population in the Sahel region expected to double by 2040?

  Due to high birth rates
• What is the relationship between population growth and land degradation in the Sahel?

  More people increase demand for food and land
• What is Niger's fertility rate?

  7.6 kids per woman
• How does migration affect the Sahel region?

  It increases population pressure and conflict
• How many trees are needed to rebuild homes?

  30-40 trees
• How many people were killed in 2003 due to conflict in the Sahel?

  250,000 people
• What is the population density of Eritrea?

  169 people per km2
• What is the population density of Mauritania?

  4 people per km2
• What is the effect of over-cultivation in the Sahel?

  It exhausts soil fertility and drains aquifers
• By what percentage has rain-fed agriculture risen since the 1970s?

  12%
• What are the pros and cons of bunds as a management strategy?

  Pros:

  • Affordable
  • Low tech
  • Knowledge passed on by people
  • Empowers locals
  • Sustainable
  • Very effective

  
  

  Cons:

  • Labour intensive
  • Small scale and local
  • Less effective with less rain
• What are the pros and cons of afforestation as a management strategy?

  Pros:

  • Promotes sustainability
  • Very sustainable
  • Reduces conflict
  • Very effective
  • Large scale
  • Multinational
  • Long term solution

  
  

  Cons:

  • Takes decades for trees to mature
  • Climate change threatens survival
  • Expensive
• What are the key facts about the Sahel region?

  • Population expected to double by 2040
  • Temperatures exceed 22°C all year
  • Yearly rainfall roughly 170 mm
  • 50 million people at risk
• Great Green Wall

  • 8000km long
  • 15km wide
  • 15% finished
  • Senegal restored 800,000 hectares because of the great green wall.