How is overgrazing responsible for land degradation

Background current

A total of 40 percent of the earth's surface is threatened by desertification - a threat to the livelihoods of hundreds of millions of people. The World Day to Combat Desertification and Drought on June 17th aims to raise awareness of the consequences of the desertification of large areas of fertile land.

A former fishing boat lies on the dried up Aral Sea in Uzbekistan. Large parts of the lake are now a salt desert. (& copy picture-alliance, imageBROKER)

World Day to Combat Desertification and Drought was proclaimed by the United Nations 25 years ago. Under the motto "Let's Grow the Future Together", this year it is not only intended to draw attention to the threat to fertile soils, but also to encourage people to think about solutions. The goal: to compensate for new desertification and land reclamation in the next 25 years.


UN Convention to Combat Desertification

Definition of desertification

In the United Nations Convention to Combat Desertification (UNCCD) of June 17, 1994, desertification is defined as "soil deterioration in dry, semi-arid and arid subhumid areas". The UN understands "soil degradation" as the "reduction or loss of biological or economic productivity and complexity" of land. This can manifest itself in erosion, the deterioration of the physical, chemical, biological properties or economic uses of the soil as well as the long-term loss of natural vegetation.

Complex causes

The causes of soil deterioration are varied. They include climatic fluctuations, but also human activities, such as overgrazing of land, overuse of soils, deforestation and the wasting of water resources.

The growth of the world population as well as poverty and the resulting consequences also contribute to desertification: Many people who live in regions with climatically and economically unfavorable conditions use the few available arable land intensively for food security. This can cause the soils to become too salty, leached and silted up. Heavy plowing can also trigger desertification processes. This in turn means that the remaining areas have to be used even more intensively. Deforestation also contributes to the desolation of soil areas.

Desertification can also be the direct consequence of political decisions. One example is the drying up of the Aral Sea in Central Asia. The body of water in what is now Kazakhstan and Uzbekistan was once the fourth largest inland lake in the world with almost 70,000 square kilometers. In the 1960s, large amounts of water began to be diverted from the tributaries to irrigate cotton plantations. As a result, large areas dried up, the lake divided into two halves, became too saline and shrank to a tenth of its size. The complete drying out could be prevented by a dam completed in 2005. Since then, the water surface has been slowly growing again.

1.5 billion people are threatened by desertification processes

Today around 40 percent of the world's land mass is "arid areas", in which desertification can occur if the soils deteriorate. The peripheral areas of already existing desert zones are particularly affected, especially in Africa, on the Arabian Peninsula and in Central Asia, but now also in southern Europe. In 2016, scientists from the Spanish public research institute CSIC published a study that found that 20 percent of Spain's land area is affected by desertification processes. According to the UN, a total of 1.5 billion people in 169 countries are affected by the effects of desertification. Currently, 23 hectares of desert areas are being created every minute, and over 50,000 square kilometers per year.

The consequences of desertification are complex: Changes in precipitation and air humidity affect the vegetation, biodiversity and soil fertility of the surrounding areas, for example droughts. Deserted soils can no longer be used for agriculture, which deprives many people of their livelihood. The consequences are famine and rural exodus. In the long term, desertification can therefore also cause migration. In the Sahel, desertification also contributed to political conflict, as nomads and settled farmers compete for scarce water resources.

International initiatives against desertification

With the "Land Degradation Neutrality" (LDN) initiative, the United Nations want to combat the ongoing desertification of the world. Stopping soil deterioration is part of the "2030 Agenda for Sustainable Development" adopted in 2015. So far, 121 countries have set voluntary targets to curb the loss of usable soils - including many African and Asian countries. Projects to stop desertification include irrigation of large areas and the development of vegetation. Forests play a special role as they bind carbon dioxide, improve soil quality and reduce wind speeds, which can prevent erosion.

One example is the "Great Green Wall" reforestation project in the African Sahel. In the area south of the Sahara, an 8,000 km long tree corridor from Senegal in the west of the continent to Djibouti in the eastern Horn of Africa is intended to curb the spread of the desert to the south. The project, which was launched in 2007 by the African Union and in which 21 countries are involved, aims to make the soil more fertile again by planting trees and thus to secure the food base and jobs in the region. Today, the major project also promotes dispersed initiatives that arise from village communities along the Sahel zone. According to Elvis Paul Tangem, who coordinates the project for the African Union, 15 percent of the trees originally planned have been planted.

Key role of women

The federal government is also taking part in measures to combat desertification. According to its own information, the BMZ is currently funding around 800 projects carried out by government and non-government agencies in the countries concerned. One focus is on promoting women who play a key role in the use of natural resources in rural areas affected by soil degradation. Involving them in decisions and strengthening their rights is also the aim of the "Gender Action Plan", which was adopted in 2017 as part of the UN Convention to Combat Desertification.

Despite these and other measures, desertification is progressing globally. According to forecasts, the world population will continue to grow in the coming years, especially in areas where large areas are already affected by desertification. At the same time, the consequences of climate change are becoming more noticeable. Extreme weather events increase and accelerate erosion processes: droughts dry out the soil, heavy rain washes away the remaining vegetation. World Day to Combat Desertification and Drought aims to draw attention to these dangers.

More on the subject:

Bruno Rudolf: When the land dries up - drought and desertification

Torsten Mertz: Soil pollution from agriculture

Frank Biermann: Environmental refugees. Causes and possible solutions

Silja Klepp: Climate Change and Migration

Dr. Carsten Felgentreff: Development and Migration, Resettlement and Climate Change