The spread of desert conditions and regions due to human activities
Desertification is a major problem in many parts of the world
Around one billion people, or 15 percent of the world's population, either experience or are threatened by habitable desert areas turning into hot desert areas
The Sahel, home to 50 million people, is where the human risks created by desertification are greatest
Natural causes of desertification
Soil erosion by wind and rain leads to loss of nutrients
Plants unable to establish and grow
Rainfall patterns becoming less predictable leading to drought and vegetation dying
Causes of desertification
1. Population growth
2. Overgrazing
3. Overexploitation of land for agriculture
4. Deforestation
5. Climate change
Population growth in desert areas
Increased pressure on the land as people raise more animals and grow more crops
Deforestation
Removal of shade for the soil means there are no roots to bind the soil together, increasing soil erosion and decreasing water infiltration
Overgrazing
Vegetation has all gone due to the numbers of animals or the land does not have chance to recover
Overexploitation of land for agriculture
Nutrients taken up by crops leaving none for future vegetation to grow
A range of human and natural factors can contribute to desertification
