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沙漠化是当今世界上的一大灾害。根据联合国沙漠化会议资料,全球三分之二的国家和地区受到沙漠化的影响,每年有5——7万平方公里的土地丧失。半个世纪以来,非洲的撒哈拉大沙漠向南扩大了65万平方公里。印度塔尔沙漠,每年以0.8公里的速度向外扩张,每年被吞没的土地达13,000公顷。沙漠化在中国也非常严重,据统计,历史上形成的沙漠化土地有12万平方公里,近半个世纪形成沙漠化土地5万多平方公里,而且还有15万平方公里的土地具有潜在沙漠化的危险,涉及12个省区,3,500万人口。因此,防治沙漠化这个题材意义重大。现在世界各国都在研究沙漠化的防治,我国
Desertification is a major disaster in the world today. According to the UN Conference on Desertification, two thirds of the world’s countries and regions are affected by desertification and each year 50,000 to 70,000 square kilometers of land are lost. For half a century, the Sahara Desert in Africa has expanded southward by 650,000 square kilometers. The Thar Desert in India expands outward every year at a speed of 0.8 km, with 13,000 hectares of land being swallowed each year. Desertification is also very serious in China. According to statistics, there are 120,000 square kilometers of desertified land formed in history, more than 50,000 square kilometers of desertified land are formed in the past half century, and an additional 150,000 square kilometers of land is in danger of potential desertification. Involving 12 provinces and autonomous regions, 35 million people. Therefore, the topic of combating desertification is of great significance. Now all countries in the world are studying the prevention and control of desertification in our country