What is the impact of humans on the desert?
Deserts are increasing in size daily. This process is known as desertification. Desertification is the process of fertile land turning into desert over time. Areas on the edge of hot deserts are especially at risk of desertification.
What are the causes of desertification?
There are five main causes of desertification. These are:
- Climate Change – hotter and drier conditions are increasing the risk of land turning to desert;
- Removal of trees for fuel – cutting down trees to use the wood for fuel leads to roots dying. The soil will no longer be held together by the roots and erosion will occur;
- Overgrazing – soil becomes bare as the result of vegetation being removed by grazing animals. The soil becomes bare, compacted and prone to drying out and cracking;
- Over-cultivation – as a population grows there is a greater demand for food. Farming becomes more intensive which means the land has less chance to recover causing it to become infertile, exposed and at risk of erosion; and
- Population growth – rising population puts a great demand on resources.
The video below explores the issue of desertification.
What is the impact of Desertification?
The Sahel region of Africa has been suffering from drought on a regular basis since the early 1980s. The area naturally experiences alternating wet and dry seasons. If the rains fail it can cause drought.
The result is crop failure, soil erosion, famine and hunger: people are then less able to work when their need is greatest. It becomes a vicious circle and can result in many deaths, especially among infants and the elderly. In 2012 a large-scale drought-induced famine occurred in the Sahel. It affected over 20 million people. You can read more about this on the Huffington Post site. In these cases, people rely on food aid from the international community. Click here to see a video from the BBC highlighting the issues.
How can desertification be managed?
There is a range of management strategies that can be used to reduce the risk of desertification. These include:
- Water and soil management – planting and harvesting appropriate crops ensure the soil can recover. Small-scale irrigation projects, such as catching and storing rainwater and using sprinklers to irrigate the land.
- Tree planting – This helps reduce soil erosion because tree roots stabilise the soil. Find out about a scheme in the Sahel to combat desertification through afforestation – the Great Green Wall of Africa
- Planting pits or Zai – planting pits are simple irrigation systems used to hold more water around the plant. The planting pit a small pit used to grow crops and catch water. They include half-moon water catchments. Water gathers in the depression and helps water the plant over time. Homemade compost is used to provide a fertility boost for the soil.
Planting pits or Zai
- Appropriate technology – this involves the use of technology or techniques that can be easily used or replaced by locals. For example, stone lines along the soil contours keep it in place, prevent erosion and improve crop yields. Projects such as this can involve the whole community and give them a sense of ownership and responsibility.