英语精读土地沙漠化问题.ppt

land desertification,The size of desert is increasing continuously. On contrast, the forests and arable land keep decreasing.,If this situation keeps going, one day we wont have enough arable land to plow and our future generations do not have enough foodstuffs to support the requirement of their bodies. People are goanna die.,Moreover, some other environment issues which were caused by desertification perplexed people such as sand storm, drought and arable land degradation and productivity decline.,Problem:,All of these problems were inconvenience to peoples daily life.,Therefore, we have to change our environment condition and protect it.,Causes:,Usually, desertification is caused by climate change or by destructive use of the land and the gradual transformation of habitable land into desert.,five main reasons on peoples actions,1. Excessive reclamation 2. Overgrazing 3. Excessive mining 4. Unreasonable irrigation 5. Industrial building,some reasons on climate:,1. Scarce rainfall, dry climate 2. Windy days and more concentrated 3. Loose soil 4. Soil erosion,Around the world, every year 6,000,000 hectares of land desertification happen. According to the China State Forestry Administrations announcement in June 17, 2006, China desertification land reached 1,739,700 square kilometers, accounting for more than 18% of land area. It is obvious that the situation of desertification is grim.,Solution:,Control desertification is one of fundamental national policies.,Desertification and the “Environmental Protection Law“ “Forest Law“ “Grassland Law“, “Soil and Water Conservation Law“ currently in the development of “Desertification Law“, also developed with the support of a series of laws and regulations.,some solutions for reducing the desertification,1. Planting trees 2. Grass speci