Responses to Desertification (Edexcel IGCSE Geography)

Desertification - Water Shortage Solutions

Spec point — 4GE1-S3.064

• Desertification can be halted and even reversed with careful management

• Water shortages are a key issue in areas at risk from desertification

  • Desalination can be used to increase water supply but the process is expensive

    • This means that only some countries can afford it

  • Groundwater can be abstracted using water pumps but care must be taken not to over-abstract

Diagram to illustrate the desalination process

Other water shortage solutions

• Other techniques and filtration systems can be used to increase the supply of clean water

  • Solar water disinfection uses solar radiation to improve water quality
  • Life straw which filters unclean water

Desertification - Other Responses

Spec point — 4GE1-S3.064

• Halting and reversing desertification means tackling the causes
• There are a variety of political and social responses

Education

• Education including:

  • Sustainable farming methods including agroforestry and crop rotation, which help to keep the soil healthy
  • Family planning to reduce population growth

Agriculture

• Focus on livestock breeds which are better adapted to drier conditions
• Reduced herd size
• Use high yield varieties (HYV)
• Crop rotation

Agroforestry

• This combines agriculture with forestry, which means some trees remain, which:

  • decreases deforestation
  • provides shade as well as increasing infiltration and interception, which reduces soil erosion
  • provides organic matter from the trees and adds nutrients to the soil

Afforestation

• Tree planting, such as the Great Green Wall across the Sahel, helps to reverse desertification in several ways:

  • The roots help to bind the soil together reducing soil erosion
  • The canopy offers shade helping to prevent the soil from drying out and also reducing soil erosion from rainfall landing directly on the soil
  • Nutrients in the soil are replaced by falling leaves and branches
  • The trees increase animal and insect activity which helps improve soil quality

Fertilisers, high yield varieties (HYV) and genetically modified (GM) crops

• Fertilisers, HYV and GM crops can:

  • Increase the yield
  • Reduce the amount of land cultivated

• HYV and GM crops may also be:

  • Drought resistant
  • Pest resistant

Contour stones and terraces

• These help to reduce soil erosion by:

  • Preventing the soil from being blown or washed away
  • Increasing infiltration of water and reducing overland flow
  • Ensuring that dead organic matter stays in one place and can decompose adding nutrients to the soil

*Contour Stones *