环境保护阅读材料:第二篇 Passage 2

第二篇 Passage 2

The Three Gorges Project

The idea of constructing a dam at the site of the Three Gorges is not new. As early as 1918, Dr. Sun Yat Sen, the pioneer of China's Revolution, suggested his program to improve the shipping conditions and to generate hydroelectric power on the Yangtze River. After 1950, thousands of scientists and technical workers were sent to survey, design and research the physical and social effects of building a dam at the Three Gorges.

The main reason for building the dam is to reduce flooding on the middle and lower reaches of the Changjiang River, where 15 million people and 1.53 million hectares of rich land are under constant threat. For the local economy to prosper, and to protect the ecology against flood damage, the Three Gorges Project has to protect the area from catastrophic floods that occur only once every 100 years instead of comparatively less serious floods that occur once every 10 years.

A second reason for building the dam is to produce hydroelectric power. After completion, the dam's annual power generation will reach 84.7 billion kilowatt-hours, supplying the much-needed energy to Central and East China and to the Chongqing Area. The income from the dam will greatly help the project's finances and loan repayment.

How will the project affect the environment? It will reduce flooding on the middle reaches of the Yangtze River, protect millions of people, avoid ecological destruction and decrease the sedimentation in the Dongting Lake, China's largest freshwater lake, so as to prolong its existence. The project will also prevent snail fever (schistosomiasis) and improve water quality in the dry season. Compared with thermal power generation, hydropower generation is much cleaner and will create none of the problems caused by burning coal. The harmful gases emitted by coal will disappear. As a result, the air will be cleaner and healthier for breathe and damage done by acid rain will be considerably reduced.

When filled, the Three Gorges reservoir will be as large as one to two kilometers wide. The rise in water level will affect the climate, decreasing the temperature by 1℃ in summer and increasing it by 1℃ in winter. The change will greatly benefit local agriculture. Similarly, an increase of wind speeds will also benefit the area. The number of foggy and rainy days in autumn will increase, but they will not affect shipping. Because of increased water levels, the white-fin dolphin, an endangered animal, and other fish will be able to survive winters. The reservoir will also reduce the length and time that seawater flows upstream sat the mouth of the Yangtze River. Besides, shipping safety around the reservoir will improve greatly because the river will be wider and deeper. Water flow in the dry season will increase, so accidents caused by ships running into rocks will be remarkably reduced.

课文词语 Words and Expressions from the Text

shipping 航运

hydroelectric power 水力发电

middle and lower reaches 中下游

catastrophic floods 灾难性洪水

Central and East China 华中华东

power generation 发电量

loan repayment 偿还贷款

ecological destruction 生态破坏

sedimentation 沉淀；沉积

snail fever; schistosomiasis 血吸虫病

acid rain 酸雨

white-fin dolphin 白鳍豚

upstream 上游