本文是一篇说明文,主要介绍了中国古代著名的水利工程——都江堰的特点和重要价值。
Dujiangyan is the oldest man-made water system in the world, and a wonder in the development of Chinese science. Built over 2,200 years ago in what is now Sichuan Province in Southwest China, this amazing engineering achievement is still used today to irrigate over 6,000 square kilometers of farmland, take away floodwater and provide water for 50 cities in the province.
In ancient times, the region in which Dujiangyan now stands suffered from regular floods caused by overflow from the Minjiang River. To help the victims of the flooding, Li Bing, the region governor, together with his son, decided to find a solution. They studied the problem and discovered that the river most often overflowed when winter snow at the top of the nearby Mount Yulei began to melt as the weather warmed.
The simplest fix was to build a dam, but this would have ruined the Minjiang River. So instead Li designed a series of channels built at different levels along Mount Yulei that would take away the floodwater while leaving the river flowing naturally. Better still, the extra water could be directed to the dry Chengdu Plain, making it suitable for farming.
Cutting the channels through the hard rock of Mount Yulei was a remarkable accomplishment as it was done long before the invention of gunpowder and explosives. Li Bing found another solution. He used a combination of fire and water to heat and cool the rocks until they cracked and could be removed. After eight years of work, the 20-meter-wide canals had been carved through the mountain.
Once the system was finished, no more floods occurred and the people were able to live peacefully and happily. Today, Dujiangyan is admired by scientists from around the world because of one feature. Unlike modern dams where the water is blocked with a huge wall, Dujiangyan still lets water flow through the Minjiang River naturally, enabling ecosystems and fish populations to exist in harmony.
都江堰是世界上最古老的人工水利系统,也是中国科学发展的一个奇迹。这座令人惊叹的伟大工程建于2200多年前,位于现在中国西南部的四川省,如今仍用于灌溉超过6000平方千米的农田,在泄洪的同时为全省50座城市供水。
在古代,都江堰现在所处的地区经常遭受岷江泛滥的洪水。为了帮助洪灾的受害者,地方长官李冰和他的儿子决定寻求解决办法。他们研究了这个问题后发现,当天气变暖,附近的玉垒山山顶上的冬雪开始融化时,河水经常泛滥。
最简单的解决办法是建一座大坝,但这会毁了岷江。因此,李冰设计了一系列建在玉垒山不同高度处的渠道,它们在泄洪的同时能够使河流自然流淌。更甚者,多余的水可以直接送到干旱的成都平原,使之适合种植。
在玉垒山的坚硬岩石上开凿渠道是一项了不起的成就,因为那时还没有火药和炸药。李冰找到了另一个解决办法。他结合使用火、水技术来加热和冷却岩石,直到它们裂开,可以移动。经过八年的奋战,20米宽的沟渠在山上凿成了。
这个水利系统一完工,就再也没有洪灾发生,人民由此能够安居乐业。如今,都江堰受到了来自世界各地科学家的赞赏,因为它有一个特点:不像现代的水坝,水会被一堵巨大的墙堵住,都江堰仍然允许水自然流经岷江,使生态系统和鱼类种群和谐共存。
wonder n. 奇迹,奇观
amazing adj. 令人惊讶的
irrigate v. 灌溉
victim n. 受害者,罹难者
occur vi. 发生
Dujiangyan is the oldest man-made water system in the world, and a wonder in the development of Chinese science.
都江堰是世界上最古老的人工水利系统,也是中国科学发展的一个奇迹。
Once the system was finished, no more floods occurred and the people were able to live peacefully and happily.
这个水利系统一完工,就再也没有洪灾发生,人民由此能够安居乐业。