Damage to fragile environments: farming and desertification in the Sahel

• High temperatures cause a high rate of evapotranspiration

• Rainfall is infrequent but intense, causing soil erosion

• Overcultivation

• Deforestation

• Change in traditional farming practices. Nomads have adopted a more sedentary (settled) lifestyle with no change in traditional herding practices

• Nomads have adopted a more sedentary (settled) lifestyle with no change in herding practices

• Overgrazing, overcultivation and deforestation

• Soil erosion

• Desertification

Farmers forced to grow crops on marginal land

• Soil erosion

• Desertification

Trees are removed for fuel and to clear land for crops

• Deforestation leads to soil erosion and:

• reduced transpiration leads to less rainfall in the region

• animal manure being used as fuel. It is no longer available to fertilise the soil, leading to reduced crop yields

• reduced crop cover. Crops are destroyed by the heavy rain when it comes

NASA AVHRR (Advanced Very High Resolution Radiometer) Image from 1986 shows the sharp boundary between the deserts to the North and the dense forests to the South on the Sahel