Responses to Desertification (Edexcel IGCSE Geography)

Desertification - Water Shortage Solutions

• Desertification can be halted and even reversed with careful management

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

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

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

Desertification - Other Responses

• 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

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