What Is Desertification?
Desertification is the process by which land turns into a desert. In other words, desertification is when land degrades over time and becomes more arid, causing the land to be less fertile and productive.
Desertification threatens human subsistence, as it makes natural resources including food and water much more difficult to obtain.
The continent of Africa is one of the most serious and most-studied areas of desertification.
Learn more: What is Desertification?
Table of Contents
Fast Facts about Desertification in Africa
- Up to 65% of Africa’s productive land is degraded and desertification affects 45% of total land on the continent (FAO report 2021).
- Over 7.5 million km2 of land in Africa is at high risk of desertification (Reich et al. 2001).
- About 400 million people live in drylands in Africa, and 22 million people live under high risk of desertification (Reich et al. 2001).
Where Is Desertification Happening?
Desertification occurs in drylands, areas that get less rain (precipitation) than is evaporated or consumed by plants through part or the entire year. Drylands have very limited water and soil moisture. Because Africa has one billion hectares of drylands, much of the continent is experiencing or at risk of desertification (UN FAO 2021).
Desertification is happening in many countries in Africa, but is most extreme in the Sahel region. This belt of land is south of the Sahara desert and extends east to west 5000km across the continent. It includes parts of the countries Senegal, Mauritania, Mali, Burkina Faso, northern Nigeria, Niger, Chad, Sudan, and Eritrea.
Temperatures in the Sahel are rising rapidly at a much faster rate than the global average. According to the Intergovernmental Panel on Climate Change (IPCC), the Sahel will experience higher degrees of warming sooner than the rest of the world (UNFCCC 2020).
Desertification in Africa is not limited to the Sahel region. Even countries farther from the Sahara such as Ethiopia may experience higher rates of desertification in coming years. At least 70% of Ethiopia is threatened by desertification, and 80% of land in Kenya is vulnerable to desertification as well. It is important to note that simply because these areas are more prone to desertification does not mean that desertification will necessarily occur.
The map below shows areas of high vulnerability to desertification in red. The red swath in the north is the Sahel region.
Why Is Desertification Happening?
Desertification is caused by multiple factors, including natural causes and human activities. The factors discussed below are some of the major drivers of desertification in Africa, but do not represent a comprehensive list.
As climate change continues and temperatures rise, land becomes more arid and more vulnerable to desertification. The amount of precipitation (rain) that is occurring in deserts today is generally much lower than the amount of rain a half century ago (UNFCCC 2020).
Extreme weather events like drought are a major driver of desertification, and are becoming more intense and more frequent as a result of climate change (UNFCCC 2020). As much of the Sahel is already susceptible to drought, climate change may cause more extreme drought in this area.
Flooding caused by climate change can also contribute to loss of soil through landslides and erosion, which causes land degradation and desertification.
As seen on the map below, climate change is causing drylands to expand and shift. This shift will cause new desertification, as many of these areas will become unable to support agriculture or livestock.
Population Growth and Urbanization
Higher urbanization and increased population growth leads to higher resource extraction and increased pressure on surrounding agricultural areas (Abdelbagi 1982). More resource extraction like logging, farming, and land clearing leads to faster desertification, as does land clearing.
Higher populations create higher vulnerability to desertification. Africa’s population is extremely fast-growing, and is expected to double by 2050 (Economist Report 2020). Not only will a larger population contribute to desertification by stripping land of its resources, but it will also make it more difficult to provide enough resources for everyone, thereby becoming a human rights issue.
The map below shows land use in Africa. As desertification makes cropland less and less available, more people will be forced to move or to live on infertile land without resources.
Some people are also resorting to clearing forested areas to create new cropland, a practice which in turn contributes to desertification and lower soil health (Reich et al. 2001). According to the UN FAO, nearly 30 million hectares of land in Africa are degraded due to land use changes such as deforestation (FAO report 2021).
Unsustainable Agricultural Practices
There are many agricultural practices that degrade land and contribute to desertification. First, removing protective layers of vegetation on top through tilling erodes land and degrades the soil, leaving infertile soil levels below to dry out in the sun (Winslow et al. 2004).
The use of chemical fertilizers and pesticides also works to degrade soil, as they kill off helpful microorganisms in soil and remove crucial nutrients for plant growth (Joko et al. 2017).
Overgrazing livestock additionally erodes land and makes it more difficult for new plants to grow.
These agricultural practices are widely used in Africa which greatly contributes to land degradation (Reich et al. 2001). Land must be used in specific ways that match the land’s composition. For example, some desert areas of Africa may be better for irrigated agriculture, while other areas are better suited to nomadic grazing.
Natural Soil Composition
Desertification is also particularly threatening in Africa due to the natural makeup of the soil. Much of the soil in Africa is on bedrock made of granite, which naturally has lower soil fertility than sedimentary soil (although the continent does have sedimentary soil as well) (Ward et al. 2017).
Additionally, much of Africa’s soil has very little clay, which makes it more susceptible to erosion by wind or water.
Impacts of Desertification
Desertification is already having severe impacts, and will continue to cause harm both to human economies and subsistence styles, and the environment.
Reduced Food Security
In sub-Saharan areas that are prone to drought and desertification, the number of people who are undernourished has increased by nearly 50% since 2012 (UNFCCC 2020). As agriculture becomes more difficult on increasingly degraded and desertified land, food scarcity increases.
According to the IPCC, under the worst case climate change scenario (if we continue business as usual), crop yields will be reduced by 13% in West and Central Africa, 11% in North Africa, and 8% in East and Southern Africa (UNFCCC 2020).
Desertification may cause increased risks of water and food-borne diseases. This is partially due to a lack of clean water (Mirzabaev et al. 2019).
Increased dust in the air can result in respiratory problems or heart disease (Zhu et al. 2022).
Desertification may lead to increased social instability and conflict. Several studies have found that the likelihood of violent conflicts and crime increases with less rainfall and higher temperatures. For example, a 2017 study found that increased dryness raised the likelihood of riots in Sub-Saharan Africa by 8.3% (Almer et al. 2017). However, this general theory was disputed (Buhaug et al. 2014).
For more information on the impacts of desertification, read “Desertification: Definitions, Causes, Impacts, and Solutions.”
Solutions to Desertification in Africa
Many solutions have been developed and some have been implemented to try and address desertification in Africa. This article discusses a few solutions, but a wide variety of community-based approaches are needed to address the problem of desertification.
The Great Green Wall
The Great Green Wall project is a proposal to plant an extremely long wall of trees that spans the width of the continent. The Wall aims to fight desertification and its effects by reducing droughts, increasing soil fertility, reducing soil loss, and allowing for increased agriculture and jobs.
After the initiative began in 2007, 15% of the wall has been implemented. It is being grown in the area worst affected by desertification, the Sahel. Currently, the wall exists between Dakar and Djibouti and is 15km wide and 7,100 km long.
Implementation of Regenerative Agricultural Practices
Regenerative agriculture is agricultural practices that restore the land, rather than depleting the land of vital resources.
Regenerative practices that restore soil health include agroforestry (planting trees among crops), low or no-till farming, planting cover crops, and using natural, chemical-free fertilizers and pesticides.
Planting drought-resistant crops may additionally work to protect communities against the effects of desertification. For example, the UN Framework Convention on Climate Change projects the crops millet and sorghum to decrease in yields by only 5% and 8% respectively by 2050 under the worst climate change scenario due to their resilience to high temperatures (UNFCCC 2020). Rice and wheat, however, are expected to experience yield decreases of 12% and 21% respectively by 2050.
Read more: What Is Regenerative Agriculture?
Rain-fed farming in Africa may also reduce drought impacts by 20-30% (Cervigni and Morris 2015). As seen in the chart below, increased use of rain-fed farming reduces the number of drought-affected people, as compared to business as usual. This strategy is, of course, dependent on rain. While the Sahel experienced flooding in 2019, and is projected to experience high amounts of rainfall in the next 5 years, rainfall overall may not be a dependable resource (UNFCCC 2020).
Some desertification-resistance solutions focused on regenerative agriculture have already been implemented in several countries in Africa. For example, the International Crops Research Institute for Semi-Arid Tropics (ICRISAT) provided women in Niger with training on agricultural techniques to avoid desertification, such as creating pits to store rainwater, using regenerative fertilizer practices, and growing drought-resistant crops. This initiative doubled household incomes and reduced malnutrition.