What is desertification? Causes of desertification. Where does desertification take place?

Numerous studies have long proved that the number of fertile land on our planet decreases annually. According to the tentative calculations of scientists, during the last century about a quarter of the land, suitable for processing, went out of order. This article will discuss what is desertification, as well as the causes of its occurrence and its impact on the global ecosystem.

General concept

The very concept of "desertification" has several synonyms. In particular, it is also called desertification, the Sahelian syndrome and the progressive formation of deserts. This phenomenon refers to the process of land degradation that occurs in different parts of the world. The main causes of desertification, which are distinguished by scientists, are human activities and global climate change. As a result, in some areas of the planet there are zones where environmental conditions become similar to desert. Annually because of this problem on Earth about twelve million hectares of fertile land is lost. Moreover, scientists from all over the world state a steady progression of this trend.

Recognition of the problem

For the first time, humanity realized the seriousness of the problem and started talking about what desertification was, in the early seventies of the last century. The reason was a severe drought in the African natural zone of Sahel, which led to a catastrophic famine in the region. As a result, in 1977, a conference was held in Nairobi, the capital of Kenya, under the auspices of the United Nations, the main theme of which was the identification of the main causes and measures to combat land degradation.

The main types of human intervention

As already noted above, there are two main causes of desertification - the natural factor and people's activities. While the first of these, humanity can not affect in any way, then the situation can be largely improved by the second. The most common activities that lead to the progressive formation of deserts are grazing, excessive and irrational use of arable land, as well as massive deforestation in arid regions of the planet.

Pets

At the UN conference mentioned above, scientists came to a common opinion that the eating of vegetation by livestock is the most common type of human intervention in nature, leading to desertification. In this case, we mean the fact that now, like more than thirty years ago, the number of grazed animals per unit of land in arid climates is significantly overestimated. This leads to the fact that the plant cover is constantly thinning, and the soil loosens. This results in soil erosion, deterioration of plant development conditions and desertification of land.

Irrational use of arable land

This factor is the second in its scale and perniciousness. More specifically, it consists in reducing the periods of rest of the land, as well as plowing up areas located on the slopes, which leads to increased soil erosion and a reduction in vegetation cover. The situation is exacerbated and because of uncontrolled use of pesticides, due to which the soil is fertilized. In addition, heavy agricultural machines working on them compact the soil, resulting in the death of useful species of living beings (for example, earthworms).

Deforestation

Another area of human activity, which leads to the emergence of the Sahel syndrome, has been massive deforestation. The most common places where desertification occurs for this reason are the densely populated African regions, in which wood is nowadays an important energy source. They are also considered one of the most arid regions of our planet. The fact is that the need of local residents in wood for heating and building, as well as the destruction of forests to increase the number of arable land, led to the emergence of this global problem.

Natural factor

In addition to human activities, there are also natural causes of desertification. Under the influence of wind erosion, reduction of cohesion and salinization of soils, and also due to water wash-off, it only progresses. In addition, a progressive desert formation occurs under the influence of fluctuations in the natural amount of precipitation, when a prolonged absence leads not only to development, but also to the beginning of this harmful process.

Impact on countries

Speaking of what is desertification, one can not fail to note its negative impact on the economic development of many states. Some time ago, representatives of the World Bank conducted a study of one of the countries located in the natural zone of the Sahel. Their results showed that a decrease in the amount of natural resources caused a reduction in its GDP by twenty percent. According to data from another source, the total annual amount of funds that the states suffering from this problem receive less than is 42 billion US dollars. Another disastrous consequence of desertification has been the continuous emergence of interstate conflicts because of violations by residents of the borders of neighboring countries in search of water and food.

Influence on people

Desertification areas are characterized by a significant reduction in agricultural productivity, as well as a poor list of cultivated crops. Their ecosystem every year is worse able to meet basic human needs. In addition, for the regions that found themselves in the sphere of its influence, characteristic was the increase in the number of sandstorms, which resulted in the development of local residents of eye infections, allergies and respiratory diseases.

All this, in turn, can not but be shown to be harmful to people living not only in these areas, but also beyond. The fact is that the Sahel syndrome leads to a deterioration in the quality of drinking water, the silting of existing reservoirs, and the strengthening of sedimentary deposits in lakes and rivers. Among other things, the industry suffers from the production of food products. Against the background of the growth of the population of the planet, this can lead to hunger or malnutrition.

Methods of struggle

Speaking of what is desertification, it should be noted that it is very difficult to combat such a problem. To effectively combat the emergence of the Sahel syndrome, it is necessary to take a whole package of measures that includes the economic, agricultural, climatic, political and social aspects.

One of the most promising and discussed ways to overcome this problem is planting trees on arable land. This makes it possible to reduce the development of wind erosion and to reduce evaporation from the soil moisture. In addition, there are local measures to improve this situation. It is considered quite efficient to build walls of clay or stone around fields with fodder plants. At the same height of 30-40 centimeters will be quite enough in order to delay the precipitation. The most important thing is that the local population has at least an elementary concept of how to care for these peculiar dams.

Potential problems

In summary, attention should be paid to the fact that topics such as desertification, measures to combat it and ways to prevent it have become increasingly the main agenda for various conferences held by the United Nations. This is not surprising, since the degradation of soils can potentially affect about one billion inhabitants of our planet, as well as a third of all existing agricultural land. First of all, this applies to Africa, Australia, South Asia, as well as individual regions of Southern Europe.