A third of the earth’s landmass is covered by deserts. But the exploitation and deforestation of our land is destroying vast stretches of fertile soil, leading to further desertification.

Deserts emerge. There was a time when hippos and elephants lived in the Sahara. Today it's a barren landscape where few creatures can survive. A small lake fed by groundwater that fell to earth as rain thousands of years ago, serves to remind of times gone by. As the climate in the region changed, it led to the creation of a vast sandscape. Deserts are still forming today — often as a result of human activity.

Humans disrupting nature. "Desertification" describes the transition of fertile land to desert. It is often connected to human behavior. When people deplete natural resources — like water sources — in areas with a dry climate, plant life disappears and the soil becomes infertile. This phenomenon can be seen in 70% of the world's arid regions, such as in India, as pictured.

Global threat
Every year, about 70,000 square kilometres (27,000 square miles) of desert are created. That’s equivalent to the size of Ireland. According to the German development agency, GIZ, 40% of Africa's population live in areas threatened by desertification. In Asia and South America it is 39% and 30% respectively. But places such as Germany, the US and Spain are also at risk.

Overgrazing
One reason for the proliferation of deserts is population growth. In China, for example, the soil is being used to feed more and more people. Farmers crowd their pastures with animals that eat every last plant. The soil is loosened and eventually eroded by wind and rain. This creates some 2,500 square kilometers (965 square miles) of desert in the country every year.

A lake without water
The Aral Sea on the border between Kazakhstan and Uzbekistan illustrates a failed agricultural policy that led to desertification. In the past, the Aral Sea was the fourth largest lake in the world; today there is little left of it. Since Soviet times, the two neighboring countries have tapped the lake to irrigate cotton fields. Fishing boats are now stranded on land.

When forests give way to tourists
European countries can also suffer from cracked soil and dried up waterways. In Spain, desertification is accelerating — triggered by the demand to accomodate an influx of tourists from all over the world. Whole forests are often cleared for the construction of hotels. The soil is disrupted and removed, or buried under concrete. The Guadalajara region near Madrid is particularly under threat.

Fleeing desertification
Desertification greatly affects lives. Without reliable sources of water and fertile soil, people struggle to survive and often have to leave places they've lived for generations. The GIZ estimates that desertification affects 485 million people in Africa. The UN predicts that more than 60 million people will have been forced to leave the desert regions of Africa by 2020

The fight against deserts
Some countries have declared war on desertification. For decades, China has been trying to counter this trend by reforesting. Its "Great Green Wall" project, which began in 1978, has an ambitious goal — to replenish an area the size of Germany by 2050. On the World Day to Combat Desertification, the United Nations wants to draw attention to this increasingly urgent problem..