3.2.5.2. Effects of Desertification

Desertification reduces the ability of land to support life, affecting wild species, domestic animals, agricultural crops, and people.

Desertification significantly harms the land, making it less productive. This means the land can no longer provide sufficient food or habitat for wild animals, livestock, and crops. As a result, people who rely on this land for food and livelihood face serious challenges.

Imagine a farmer who has a patch of land that was once fertile and could grow a variety of crops. Due to desertification, the land becomes dry and cracked, unable to grow anything. This farmer now struggles to feed their family or sell crops in the market, mirroring the situation faced by many communities affected by desertification.

The reduction in plant cover that accompanies desertification leads to accelerated soil erosion by wind and water. South Africa loses approximately 300-400 million tonnes of topsoil every year. As vegetation cover and soil layer are reduced, raindrop impact and run-off increases.

As plants die off because of desertification, the soil becomes exposed and vulnerable to erosion. Without plant roots to hold it together, soil gets washed away by rain or blown away by wind. This loss of soil, particularly topsoil which is rich in nutrients, means less fertile land overall, reducing the land's ability to produce crops.

Think of a sponge—the sponge represents healthy soil upheld by vegetation. When you dry a sponge out, it loses its ability to hold water. Similarly, when vegetation is lost due to desertification, the soil cannot retain moisture or nutrients, leading to greater erosion, much like a dried sponge in a rainstorm.

Water is lost off the land instead of soaking into the soil to provide moisture for plants. Even long-lived plants that would normally survive droughts die.

Desertification affects how water is absorbed into the soil. When surface vegetation is removed, rainwater runs off instead of being absorbed, making it harder for plants to receive the moisture they need. Over time, even resilient plants that normally withstand dry conditions will fail due to lack of water.

Imagine a sponge again; if placed on a flat surface, the water will just run off instead of being absorbed. Similarly, when the soil is bare due to desertification, rain falls but doesn’t penetrate the ground, leading to dry conditions that hurt plants.

A reduction in plant cover also results in a reduction in the quantity of humus and plant nutrients in the soil, and plant production drops further. As protective plant cover disappears, floods become more frequent and more severe.

As plant life diminishes due to desertification, the amount of humus (organic matter that enriches soil) also decreases. This results in poorer soil quality which cannot support diverse plant life, leading to further declines in vegetation. Less vegetative cover means that rainwater can’t be absorbed quickly, which leads to flooding during heavy rains.

Consider a sponge again; when a sponge is rich and moist, it soaks up water. As it dries out and disintegrates, it becomes unable to perform its function. Similarly, without vegetation, soil cannot handle rain efficiently, leading to increased run-offs that cause localized flooding.

Desertification is self-reinforcing, i.e., once the process has started, and conditions are set for continual deterioration.

Desertification can create a cycle where the initial degradation leads to further degradation. For example, as vegetation dies, soil quality worsens, which leads to the death of even more plants, creating a downward spiral that is difficult to escape from without intervention.

It's like a small snowball rolling down a hill—once it starts rolling, it gathers more snow and grows larger. Similarly, when land begins to desertify, the process accelerates, making recovery much harder with each passing year.

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