Desertification

Desertification is when good land slowly turns into a desert. This happens because of nature and things people do. The biggest reason is when plants that hold the soil disappear.

When plants are gone, wind can blow the soil away, or rain can wash it away. This leaves dry, hard land where nothing can grow. Places where this happens often have people who find it hard to grow enough food.

Areas most affected by desertification are in Africa, like the Sahel region, parts of Asia such as the Gobi Desert and Mongolia, and some parts of South America. Drylands cover a big part of Earth's land and are where many people live. This process can cause sand and dust storms, make food harder to find, and increase poverty.

We can help fight desertification by making soil better, planting trees, caring for animals, and helping deserts grow green again. People started studying desertification after a big drought in the Sahel in the 1980s.

Definitions

Desertification is when soil becomes drier and can't grow plants as well. It happens in dry places because of natural changes and things people do. One big reason is when people cut down too many trees, farm in harmful ways, or when there are long dry periods without rain.

Many people describe desertification differently. A usual way is when good land turns into desert because of things like cutting down forests, drought, or poor farming. This shows how people and nature together can hurt the land.

Causes

See also: Deforestation § Causes

Deserts form mainly when plants and trees are lost from the land. Without plants, soil can be blown away by wind or washed away by rain. This leaves the ground dry and hard, making it difficult for new plants to grow.

People can make this happen faster in several ways. Farming, raising animals, and cutting down trees for wood all remove plants that protect the soil. Changes in climate, like long dry periods, can also help deserts grow. Scientists think that both natural changes in Earth's climate and human actions together cause deserts to spread. In some places, human actions are the bigger cause, while in others, natural weather patterns matter more. As the world gets warmer, dry areas are likely to become drier and turn into deserts faster. This can affect many people, especially where resources are limited.

Effects

Dust and sand storms happen more often because of desertification. When land turns to desert, there is more loose sand and dust. The wind picks this up and creates storms. These storms can make people sick and damage water supplies. They can also stop transportation.

Desertification makes it harder to grow enough food. As more people live on Earth, we need more food. But desertification takes away good land for farming. This can cause problems for people who need the land to live. It can also make people move from farms to cities, where they might face poverty and crowded living conditions. Many dry areas, especially in developing countries, are struggling because the land can no longer support their communities.

Geographic areas affected

Drylands cover about 40–41% of Earth's land and are home to more than 2 billion people. Experts think that around 10–20% of these dry areas have already become less fertile. This means that millions of square kilometers of land is affected by desertification. About 1–6% of people living in drylands live in areas that have turned into desert.

The Sahel region in Africa shows how climate change and human actions lead to desertification. This area has a dry, hot climate with little rain. Because of this, droughts are common. Over the past 50 years, the Sahel has lost a lot of farmland.

In the Gobi Desert area, which spans Northern China and Southern Mongolia, desertification is happening very fast. Each year, a large area of grassland turns into desert. In Mongolia, much of the grassland is at risk. Most of this is caused by people, like overgrazing with animals and cutting down trees. Warmer temperatures and less rain make the problem worse.

South America is also at risk. Much of its land is dry, and some of it has lost its fertility because of deforestation and overgrazing. In countries like Bolivia, Chile, Ecuador, and Peru, much of the land is at risk. In Argentina, Mexico, and Paraguay, more than half of the land can no longer be used for farming. In Central America and parts of Mexico, desertification has led to unemployment, less food, and people having to move to new places.

Reversing desertification

See also: Deforestation § Control

There are ways to help stop and even fix desertification. Some of these ways need help from leaders and money, while others just need people to make smart choices.

One big challenge is that using good farming methods can cost more than it helps individual farmers, even though it’s good for everyone and the environment. Another problem is that sometimes leaders don’t make enough effort or have enough money to support projects that bring back damaged land.

Improving soil quality

Main article: Soil regeneration

We can help poor soil by giving it water and making it richer. One way to protect soil is by planting rows of trees and bushes called windbreaks. These block wind and keep soil from blowing away.

Some soils, like clay, can become hard without enough water. Special ways of digging, like making small trenches along the land, help water stay in and protect the soil. Plants like certain types of beans and trees can also make soil healthier by adding important nutrients.

Desert greening

Main article: Desert greening

See also: Afforestation

Different deserts need different ways to bring them back to life. In some very dry places, like the Rub' al Khali desert in Saudi Arabia, we can grow crops using seawater without needing fresh water.

A successful method called Farmer-managed natural regeneration has helped bring back trees and land in Niger. This simple method lets local trees grow by carefully cutting back unwanted plants. This not only helps the soil but also gives more space for crops to grow.

China has created a huge “green wall” to fight desert spread. This big project has planted billions of trees, which has helped reduce desert land and sandstorms. Because of this success, similar plans are being made in Africa to help stop the Sahara desert from growing.

Better managed grazing

Restoring grasslands can help store carbon from the air. One way to manage grazing is by using fences to move animals from one small area to another often. This lets the grass grow better.

Agrivoltaics

Researchers in China found that putting solar panels over crops in dry areas can help the land. The panels give shade, block wind, and help keep soil moist, which is good for plants. This method is being tested on a large scale to help fight desertification.

History

Further information: Historic desertification

The world's most famous deserts formed slowly over time through natural processes. For much of history, these deserts grew and shrank without any help from humans. Some old deserts, now covered in plants, stretch beyond where deserts are today, like the huge Sahara.

We have clues from the past showing that land damage happened many centuries ago in dry areas, especially around the Mediterranean, the Mesopotamian Valley, and the Loess Plateau in China.

People first talked about this topic not long after the French colonization of West Africa. Researchers studied how the Sahara Desert might have grown long ago. Today, people studied desertification more closely during the tough 1980s drought in the Sahel.