Desertification

Land Desertification refers to land degeneration, which is also called 'Soil desertification'(Figure 1）

Figure 1:Desertification

In 1992, United Nations Environment and Development Conference made this definition for Desertification concept: "Desertification is a result to the factors of climate change and human unreasonable economic activities, which makes degradation occurs in the arid, semi-arid and sub-humid lands.

Figure 2: Soil degradation around the world

With the development of the society, desertification has become not only an ecosystem problem, but also an economical and social problem which could bring poverty and social instability. by the end of 1996, the total amount of desertification lands all around the world has reached 36 million square kilometer, accounting for 25% of  total land area on the earth. Countries around the world affected by desertification has more than 100, although people of all countries are conducting fight desertification, but at an annual rate of 50,000-70,000 expanded square kilometers, equivalent Ireland area. The twentieth century, the world will lose about a third of arable land. In humans in many of today's environmental problems, desertification is one of the most serious disasters. For people threatened by desertification, desertification means that they will lose the basis of being more basic - the disappearance of productive land. As we could see from Figure 2, the most serious degradation concentrates on Africa, China and the countries around the Mediterranean.
The causes of Desertification is various, including natural causes, climate causes, and human irrational production activity. Based on the causes, the management of desertification is obvious.

Figure 3:Plant in the polygonal ground

1. Setting sand-protecting barrier at migratory dune to weaken the erosion of wind and at the meanwhile save the rainfall to promote plant growth.
2. Control the development density of water resources, biological resources and land resources and avoid over-destroy the natural plants. Therefore, protecting and rebuilding the desert ecosystem is the basic way to restrict the expansion of desertification.
3.Control the population. Keep the population in the range of Environmental Bearing Capacity.
4. Plant more psammophytes in the desert areas to prevent the expansion of desert and promote the quality of land.
5. Using the water resources in an efficient way in terms of drawing water, water delivery and irrigation.

All in all, in the desertification, human activities play an important role; therefore, it`s no time to delay for human to take some actions to protect our own earth!




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