This guide was developed to help provide an overview of global desertification. We provide context and background information to help you understand what desertification is, what causes it, how it impacts people and wildlife, and how we can address it.
See the table of contents below for quick navigation.
Summary of Key Points
- Desertification is the process by which land degrades, becoming more arid and less productive.
- Desertification is caused by a number of factors, including harmful agricultural practices, overuse of resources and climate change.
- Desertification makes it more difficult to obtain natural resources and reduces biodiversity.
- There are many solutions that can help reduce and reverse desertification including soil conservation, sustainable resource management, and regenerative agriculture.
- Get the facts quicky: Desertification Facts Sheet
Table of Contents
What Is Desertification?
What Causes Desertification?
Where Is Desertification Happening?
Effects of Desertification
Solutions: Preventing and Reversing Desertification
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.
Through desertification, previously fertile land becomes infertile and loses biological and economic productivity.
Desertification is most threatening to arid or semi-arid environments, known as drylands, which cover 40% of Earth’s land surface. Around 1 billion people live in these environments (Veron et al. 2006).
Due to varying definitions of desertification in the last 80 years, desertification is often confused with drought. However, desertification differs from drought because it is caused by a degradation of land resources, rather than being a natural hazard.
What is Land Degradation?
Desertification causes land degradation, which is a reduction in the ability of land to produce resources that fulfill biological and human needs. Some scholars define land degradation as solely an economic, rather than ecological loss (Kassas et al. 1995).
Many researchers say that land degradation through desertification is one of the biggest challenges humanity faces today, as continued degradation will result in extreme hunger and other serious consequences.
According to the United Nations Convention to Combat Desertification, desertification already impacts 250 million people today, and could displace 135 million people by 2045.
What Causes Desertification?
Desertification is caused by multiple factors, including natural causes and human activities.
Land degradation has increased over the 20th and 21st centuries, partially as a result of harmful agricultural and livestock practices, increased urbanization, deforestation and climate change.
Harmful Agricultural & Livestock 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.
Overuse of Natural Resources
Overusing natural resources such as wood or oil harms soil health and removes nutrients. This causes desertification as land is made less fertile.
Water is a vital resource for fertile land. When too much groundwater is extracted from underground aquifers (often used for irrigation), desertification occurs. This process is referred to as “over drafting.” For example, the freshwater Aral Sea in Kazakhstan and Uzbekistan was overused for irrigation and shrank, leaving the area without enough fresh water to support farming or fisheries.
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.
Urbanization may also cause harmful chemicals to leach into water or soil near agricultural areas, which impacts farming and hurts crops.
Not only is desertification caused by urbanization, but desertification actually increases urbanization as people are forced off previously fertile land into urban areas. This positive feedback loop is part of what makes desertification so difficult to combat.
Deforestation (removal of trees) causes desertification, as trees work to store water and prevent erosion. Trees also provide shading of the land to slow water evaporation. Trees are also an important actor in the water cycle, and without them the land often becomes drier (Olagunju 2015).
Deforestation also increases the risk of fires, which lead to desertification as well due to increased erosion and soil loss following fires (Neary 2009).
Climate change as a whole is causing desertification to accelerate. First of all, climate change is causing the land to warm at a much faster rate than water (Joshi 2008). Higher land temperatures make it more difficult for plants to grow, which in turn reduces soil health and allows for erosion (due to a lack of vegetation cover).
While climate change is human caused, not natural, it causes a host of natural weather events that contribute to desertification, such as droughts, forest fires, and coastal flooding (which increases salt levels of the soil).
Where Is Desertification Happening?
Desertification is occurring around the world, on all continents except Antarctica. In fact, 10-20% of all arid and semi-arid environments are already degraded.
“Drylands” are the areas most threatened by desertification. Drylands can be defined as 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.
There are several biomes, types of natural communities, that may be considered drylands, are are arid or semi-arid, including:
- Some forests
- Mediterranean ecosystems
These dryland areas are shown on the map below. Areas in red are the most arid.
Desertification is affecting Africa, China, Australia, and countries in South America the most. While land degradation is truly a global threat, 37% of arid areas in Africa, 33% are in Asia, and 14% are in Australia.
Many areas of desertification also experience poverty.
Read more about desertification in Africa, China, the U.S., Japan, Ethiopia, Namibia, and Sudan.
Effects of Desertification
Desertification is already having severe impacts, and will continue to cause harm both to human economies and subsistence styles, and the environment.
Lack of Resources
People around the world depend on the land for resources, some more directly than others. Many resources that we depend on are ultimately dependent on plants, which are dependent on water and fertile land.
Desertification makes the following natural resources much harder to produce or obtain:
- Wood for burning to create fuel
- Construction materials
Poor people are most affected by desertification because they are the most dependent on these resources directly, and are most dependent on agriculture in the drylands (Winslow et al. 2004).
Reduced Food Security
Desertification significantly reduces food security. As fertile land decreases, the amount of food that can be grown also decreases.
This will become an increasingly large problem as global populations rise and arable land decreases. Food production must be intensified to meet rising demands, but must be done in a sustainable manner in order to avoid further desertification.
Reduced Water Access
Desertification causes a reduction in the supply of drinking water as the amount of water stored in the ground in natural aquifers decreases. A lack of water is a large driver for migration caused by desertification.
This lack of water also has environmental effects, such as increased risk of fire.
Increased Risk of Disease
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).
Additionally, as cities expand into previously farmed areas (as a result of climate migrations and migrations due to desertification), the transmission of diseases between animals and humans becomes more prevalent. Therefore desertification increases the risk of zoonotic diseases, albeit in an indirect way.
Increased Climate Change
Desertification reduces the ability of soils to store carbon, as healthy soil stores more carbon. Land where plants cannot grow also means that there are fewer plants to store carbon. Thus, not only is desertification caused by climate change, but it also works to intensify climate change.
Desertification causes biodiversity loss (Mirzabaev et al. 2019). As vegetation is lost, fewer species can survive. This loss of vegetation and the increased aridity of land also destroys habitats. Without important habitats, some organisms may die off.
Solutions: Preventing and Reversing Desertification
Researchers and policymakers have been crafting solutions for desertification since the 1970s. Following the UN Conference on Desertification in 1977, which focused on addressing drought and famines in Africa, researchers have continued to come up with a wide array of strategies to combat the issue (Kassas et al. 1995).
Ultimately, solving desertification will require addressing it from multiple different angles. Additionally, while researching these strategies is an important step in addressing desertification, many solutions include challenges in implementation that must be overcome. The solutions described here are just a few of the many solutions that may work to combat desertification.
Regenerative agriculture is agricultural practices that restore the land, rather than depleting the land of vital resources. Regenerative practices slow land degradation while still allowing for production of food. Regenerative agriculture will be a crucial tool in allowing us to feed global populations without causing further desertification (Rhodes 2017).
Regenerative agriculture helps prevent some of the causes of desertification such as flooding and drought, as well as soil erosion and soil loss through runoff. Regenerative agriculture improves soil health, thus making it more fertile and allowing it to capture more carbon.
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.
Read more: What Is Regenerative Agriculture?
Soil Conservation and Restoration
Highly related to regenerative agriculture is soil conservation and restoration, which will help make land more fertile and protect it from desertification. Healthy soils hold more water and aids in filtering chemicals, which can help reverse desertification as well (Eswaran et al. 1998).
The goal is to prevent soil erosion and loss of nutrients, and reduce soil acidification. Additionally, it is important to prevent salinization of freshwater sources (when freshwater becomes salt water) in order to keep soil healthy and useful.
Planting cover crops and trees, as described above, helps protect soil from being blown away or eroding into water. Restoring soil health through regenerative grazing practices such as rotational grazing allows for increased nutrient cycling, which can make the land more fertile.
Biodiversity is the variety of animal and plant life that exists. Preserving biodiversity means keeping a variety of different types of animals and plants alive. Biodiversity and desertification are closely intertwined; not only is desertification caused by biodiversity loss, but it contributes to biodiversity loss as well (Safriel 1997).
As habitats degrade, land becomes unable to support a wide variety of species. Biodiversity helps keep ecosystems healthy and thriving, so increasing biodiversity in areas experiencing or prone to desertification can help restore the natural cycles of the ecosystem.
There are a number of ways to increase biodiversity in drylands, including introducing dryland species that can evolve to withstand higher temperatures or less precipitation. Introducing drought-resistant or fire-resilient plants and animals (including crops) can increase the dryland ecosystem’s ability to respond to desertification and its causes.
Another way to maintain biodiversity is crop rotation and diversification in farming. Crop rotation is the farming practice of growing different types of crops in the same area over different seasons. It increases soil fertility as the same crop does not use up all the same resources, and instead, crops can use a variety of available nutrients. Crop rotation and diversification
Growing diverse crops and rotating crops not only leads to balanced nutrition for those who eat the crops, but also leads to higher crop yields and improved soil health, thus fighting desertification.
Sustainable Resource Management
Education and regulation to increase sustainable management of natural resources is a crucial step in fighting desertification. This includes farming practices to increase resources as well as creating alternatives to resource depletion.
This may come from improving local governance or through direct community action. One example is the work of the International Crops Research Institute for Semi-Arid Tropics (ICRISAT), which works with communities and local governments across Africa to teach about and build desertification-resistant farming techniques.
For example, 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.
Early Drought & Desertification Warning
Creating systems to monitor and warn susceptible areas about oncoming drought and desertification may help communities take action before desertification has created large impacts.
Some researchers are working on alert systems that use remote sensing, satellite soil moisture monitoring and weather forecasts to monitor possible drought conditions (Ribeiro et al. 2021).
These alert systems must come hand in hand with strategies to proactively protect against drought, such as growing drought-resistant plants.
Read about more solutions to desertification:
- Global Drylands Center – Arizona State University’s Global Drylands Center performs research on drylands stewardship in order to provide education and create solutions.
- United Nations Convention to Combat Desertification – The UNCCD’s website provides in-depth explanations of the issues related to desertification, as well as actions being taken to stop desertification.
- UN Convention to Combat Desertification Film Series – This series of 5 short films was created for Desertification and Drought Day 2021, and is focused on raising awareness for land restoration. Their 2020 film series is focused on food and desertification.
- “The Great Green Wall” – This feature length documentary focuses on land degradation in Africa and how the building a “great green wall” of trees stretching the width of Africa aims to combat desertification.
- “Kiss the Ground” – This 2020 documentary focuses on the importance of soil health in combating climate change, and focuses on land degradation, desertification and regenerative agriculture.
- “How to Fight Desertification and Reverse Climate Change” – This TED talk by Allan Savory, a leader in restorative agriculture, discusses the danger of desertification and discusses innovative solutions to stop it.
- The Threatening Desert: Controlling Desertification by Alan Grainger – This book describes the problem of desertification and explores different methods of action to stop desertification. Originally published in 1990, the book also analyzes both failed and successful prior attempts to slow desertification.
- The Next Great Migration by Sonia Shah – This book relates historic climate-caused migrations to modern day climate-migrants (including those migrating due to desertification), arguing that climate migration can be seen as a source of hope, rather than fear.
- Landesa Podcast on Desertification & Drought – Landesa Rural Development Institute discusses how rural women are affected by land degradation and how extending land rights can help prevent desertification.
- Stuff You Should Know – A 2010 episode of this long-running podcast discusses what causes desertification and possible solutions. This is an accessible and more introductory resource.