一次旅行(英语文章)

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PART II DICTATION?

Disappearing Forests?

The world’s forests are disappearing. As much as 1/3 of the total tree cover has been lost since agriculture began some 10,000 years ago. The remaining forests are home to half of the world’s species, thus becoming the chief resource for their survival. Tropical rain forests once covered 12% of the land of the planet, as well as supporting at least half of the world’s species of plants and animals. These rain forests are home to millions of people. But there are other demands on them. For example, much has been cut for timber. An increasing amount of forest land has been used for industrial purposes or for agricultural development such as crop-growing. By the 1990’ s less than half of the earth’ s original rain forests remained, and they continued to disappear at an alarming rate every year. As a result the world’s forests are now facing gradual extinction.?