The world desertification in constant diffusion. According to the UN environment programme (unep) to the world desertification assessment, global desertification land is also expanding, increased from 1984, 3.475 billion hectares to 3.592 billion hectares, 1991 increased by 3.4%. Around the world each year, 50000-7 square kilometres of land into land desertification, due to loss of desertification every year to 6 million hectares of cultivated land.
Is a type of desertification, desertification is the main cause of climate factors and human irrational activities. Desertification has serious harm on the human social and economic life. Windbreak and sand-fixation and reasonable water use are two key problems of the governance of desert, therefore to carry out project management, plant management and pumping, water and irrigation, and a series of management methods. Specific processing run method is as follows: the first kind of windbreak and sand-fixation, set the barrier. Mainly include the grass square sandy, sandy clay sandy, fence, vertical barrier, tile barrier, etc.; Second, the main way has two kinds: draw water in the well engineering and karez; Third water, water transportation mode are mainly channel water diversion and the pipeline.
the land desertification|
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