高中英语新课标人教版(广东)高一(4)unit2 workbook（在线收听）

Work book Unit 2 listening text

Fighting growing desert

Why do we have desert today? Deserts are not always being here. Most deserts we have today were once green lands full of plant life. One of today's biggest deserts is in north Africa. However, in the first centuny BC, farms in north Africa grew corn and weat, to made bread for the whole city in Broom. How did this area become desert? Both weather and people can help formed the desert, hot weather or very little rain makes the land sun trike that nothing can grow. If people cut down or burn trees and plants to make a land clear for forming, the wind can blow the soil away. And turn the dry land into sand.

Another big problem is farming on land is not very good. this poor land can really quickly turn into desert if you farmed too much. one of the biggest course however is when people take that animal to the same field to feed over and over, and the field finally lose all their new treature. because of these problems,deserts are slowly taking over green land to many parts of the world including China. However we can't fight the growing desert.In some parts of China, people are working proving desert for expending. In xinjiang for example,some farmers are trying use scientific farming methods. These methods make it possible to use less land for crops. So farmers then can plant trees on the rest of their land. One xinjiang farmer use only half of field to grow his crops last year