Climate Change Induced Desertification: Is It Irreversible?

While desertification and land degradation are common in Africa, it affects half of the Earth’s terrestrial surface, more than 100 countries, and one-third of the global population. Land degradation has risen over the past 60 years as a result of population growth, exploitation of natural resources, unsuitable agricultural practices, and climate change. The relationship between desertification and climate change is examined below.

Environmental And Developmental Problem

Desertification extends beyond the expansion of existing deserts to include land degradation due to human activity in drylands. Land degradation destroys or reduces the productivity of the soil, and is caused by excessive and unsustainable activities such as deforestation, overgrazing, poor land management, soil salinization, and soil erosion. In fact, some regions experiencing land degradation have witnessed a 50% reduction in soil productivity. The ultimate stage of land degradation is irreversible, as the soil becomes sterile and can no longer support the growth of plants. When this occurs, the environment becomes prone to soil erosion, water becomes scarce, fauna and flora disappear, and natural resources become limited, resulting in conflicts, migration, famine, and poverty. Land degradation and desertification (LLD) subjects rural populations in developing countries to a cycle of poverty as the majority of these populations are dependent on land and natural resources, and therefore puts families at stake. Farmers and ranchers often attempt to take a lead role in combating land degradation, but most lack sufficient knowledge and resources.

Who Is Affected?

Land degradation and desertification is a major challenge for humanity and affects over two billion people. Additionally, by 2050 about 9 billion people will be dependent on worsening food conditions. Most of the affected countries are located in Africa, particularly across the Sahel region, South Africa, and East Africa. Other areas include East and Central Asia, southern South America, Mediterranean Europe, North America, and Australia. In total, one-third of the global population is already experiencing desertification. Land degradation decreases the carbon storage capacity of soils and plants, which releases carbon into the air, and therefore contributes to climate change.

A Slippery Understanding

Decades of severe drought and low rainfall in the Sahel region of Africa between the 1960s and 90s were the most visible examples of climate variability during the 20th century. Since then, the Sahel and the Horn of Africa introduced the world to desertification. The impact attracted political pressure to create a permanent agency to combat the process, resulting in the formation of the United Nations Convention to Combat Desertification (UNCCD). The agency began educating the masses about environmental conservation while pushing governments to enact laws that conserve the environment. However, a major problem existed. In particular, neither overpopulation nor land mismanagement caused the Sahel drought, nor did such activities trigger the process of natural environmental decline. Initially, desertification was defined as the expansion of existing deserts. Researchers linked land degradation to poverty and poor land management, and therefore assumed the process was isolated to developing countries. However, historically fertile regions also became less productive, including regions in developed countries in North America, Europe, and Asia. Isolated areas exhibited signs of degradation, prompting the UNCCD to conclude that activities in one part of the world were affecting land degradation in other parts. In the early 2000s, it became evident that global warming was fueling desertification, provoking the process in regions thought to be safe from land degradation.

Preventing Desertification

Many agree that desertification is irreversible, not because it is technically impossible but because of the high costs of restoring the already degraded environment. Therefore, much of the discussion concerning combating desertification focus on prevention rather than rehabilitation. The common technique to prevent desertification is sustainable land management backed by effective legislative policies at local, national, and global levels. Such interventions must provide alternative livelihoods, including better agricultural practices.

Reversing Desertification

Many consider desertification a permanent process that cannot be reversed. However, individuals and organizations around the world have come up with ingenious methods of reclaiming deserts and restoring the fertility of the soil. Regardless of the method used, the common factor is the existence of vegetation. An ecosystem that supports plants is capable of hosting other living things and can initiate a natural process of restoration.

Controlled Cattle Rearing

In parts of Zimbabwe, controlled grazing is used to salvage degraded land and prevent full-blown desertification. This seems ironic given that cattle are listed as one of the major causes of desertification. However, the approach was reached by observing how wildlife ecosystems behaved. During the dry season, the environment in national parks and reserves became bare and nearly unproductive, but during the wet season, the ecosystem regenerated and reversed the desertification. After years of studying the cycle, researchers concluded that herbivorous animals played a crucial role in restricting land degradation. Perennial grasses coexisted with the soil, but as rainfall decreases and the dry season sets in, plants above the ground withered. The dead plant mass needs to decay rapidly and biologically for the plant to regenerate during the next rainy season. In the absence of herbivores, grasses and bushes overgrow, and the decaying process becomes longer, while at the same time preventing light from reaching the soil. Herbivores feed on grasses and shrubs, leaving the ground bare and ready to regenerate quickly during short rains. This process has proven successful but is only applicable in areas where desertification is not rampant.

One Tree at a Time

In 2018, a Burkinabe farmer won Sweden’s "alternative Nobel prize" for his efforts to reverse desertification in his local village. The farmer did not employ complex research or machinery but used the basic practice of planting trees. Yacouba Sawadogo observed his village slowly turn from a lush green environment to one that was extremely dire, to the point that it was at on brink of being abandoned due to a harsh climate and unproductive soil. The farmer dug pits that concentrate water and nutrients, enabling crops to grow. The technique is locally known as "Zai." Each tree grows in a pit to ensure that it does not interfere with others. Between the 1980s and 2010, Sawadogo recovered thousands of acres of land, and the practice had been exported to other villages. In 2010, the documentary The Man Who Stopped the Desert was created to highlight Sawadogo's success, who achieved what was considered scientifically unachievable. Today this approach is widespread across the Sahel region and has proven to be an effective method of reversing desertification.

Greening the Desert

In the 1980s, the Kubuqi Desert of China’s Inner Mongolia covered an area of over 18,600 km2. The vegetation was sparse and the population lived in absolute poverty, as the environment was not conducive for crop farming and livestock rearing. In 1988, the government, local authority, private investors, and the local population began an initiative to reverse desertification. There was a massive campaign to plant trees and attack desertification from all sides. Within five years, remarkable changes were achieved, and the desert shrunk by 50% within 10 years. Today, the Kubuqi Desert is a lush green environment with no signs of desertification, which is proof that a full-scale war against desertification is part of the solution.

The Science Factor

Science has investigated the causes and effects of land degradation and desertification but is yet to provide a robust solution. For example, researchers have proposed shifting clouds from the Mediterranean Sea and the Atlantic Ocean to the Sahara desert, but that is yet to be achieved. The Sahara Forest Project is piloting projects to desalinate ocean water using heat from the deserts, and then using that water to grow crops and other forms of vegetation. Nevertheless, conventional methods of environmental conservation, afforestation, and proper land management remain important methods of reversing desertification. As the global population increases, there is a growing need for fertile land to grow crops to increase the food supply. More effective methods of reversing desertification will hopefully emerge, but at the moment combating global warming and climate change are essential.