自然和人为因素使得北非乍得湖严重干枯
16 自然和人为因素使得北非乍得湖严重干枯
DATE=4-19-01
TITLE=SCIENCE REPORT - Lake Chad Shrinking 1
BYLINE=Jerilyn Watson
（Start at 1'01" ）This is Bill White with the VOA Special English Science Report.
Scientists say there has been a （1）severe decrease in the amount of water in Lake Chad in northern Africa in the last thirty years. They report that nature and humans share equal blame for this loss 2.
In Nineteen-Sixty-Three, the fresh-water lake covered twenty-five-thousand-square kilometers. Now the lake is only about five percent of that size. It measures only about one- thousand- three- hundred square kilometers in the dry season.
Four nations surround Lake Chad. People in （2）Niger, （3）Nigeria, Chad, and （4）Cameroon use it for water, fish and plant life.
Michael Coe and Jonathan Foley are water experts at the University of Wisconsin in Madison. They reported about Lake Chad in the Journal 3 of Geophysical Research. They say the area has (4) suffered from a lack of heavy rain for more than thirty years. This has forced people to build systems to carry water to dry land. These irrigation 4 systems further decrease the lake.
Mister 5 Coe says Lake Chad will be only a small body of water in the future. He says people still can get water from the lake to drink and for crops. But he says the lake will no longer (5) provide a healthy environment for fish and plant life.
The researchers used a computer to study what caused the water loss. Their computer study (6) estimated 7 the climate and amount of water in the area. The estimate 6 started with the early Nineteen-Sixties. Then the researchers compared the estimates 8 with the area's recorded climate and water supply for the same period.
The computer study showed results similar to the recorded ones for the first twenty years. But there was a big change in the Nineteen-Eighties. At that time, the lake got smaller much faster than the computer research had estimated.
The researchers say major irrigation systems were built in the Nineteen-Eighties. The systems took water from two rivers that flow into Lake Chad. The Chari and Logone rivers carry most of the water that enters the lake. The study showed the increased irrigation reduced the flow in the two rivers. Climate changes also were responsible 9 for the reduction 10. Today the flow of the two rivers has been reduced by almost seventy-five (7) percent.
Scientists say the problem is expected to worsen in the coming years as the population and demand for water continue to increase.
This VOA Special English Science Report was written by Jerilyn Watson.
注释：
(1) severe[ si5viE ]a.严厉的,剧烈的, 严重的
(2) Nigeria[ nai5dViEriE ]n.尼日利亚(非洲中西部国家)
(3) suffer[ 5sQfE ]v.遭受, 经历, 忍受vi.受痛苦, 受损害
(4) provide[ prE5vaid ]v.供应, 供给, 准备, 预防, 规定
(5) estimate[ 5estimeit ]v.估计, 估价, 评估n.估计, 估价, 评估
(6) percent[pE5sent]n.百分比, 百分数
- She purposely made the dress larger to allow for shrinking when it was washed. 她故意把衣服做大一些，以防洗时缩水。
- I can't imagine why a dynamic young woman like her is marrying a shrinking violet like him. 我不能想像，像她这样一个充满活力的年轻女子为什么会嫁给他这样一个胆怯害羞的人。
- His death was a great loss to the country.他的逝世对这个国家是一大损失。
- Because of the continued loss,the factory closed down.由于连续亏损，工厂关闭了。
- He kept a journal during his visit to Japan.他在访问日本期间坚持记日记。
- He got a job as editor of a trade journal.他找到了一份当商业杂志编辑的工作。
- Irrigation is easy in the South because of the abundance of water.南方多水，利于灌溉。
- Irrigation is important for farming.灌溉对农业是非常重要的。
- Mister Smith is my good friend.史密斯先生是我的好朋友。
- He styled himself " Mister Clean ".他自称是“清廉先生”。
- We estimate the cost to be five thousand dollars.我们估计费用为5000美元。
- The lowest estimate would put the worth of the jewel at ＄200.按最低的评估这块宝石也值200美元。
- She estimated the breadth of the lake to be 500 metres. 她估计湖面大约有500米宽。
- The man estimated for the repair of the car. 那人估算了修理汽车的费用。
- Unofficial estimates put the figure at over two million. 非官方的估计数字为200万以上。
- We got estimates from three different contractors before accepting the lowest. 我们得到3个承包商的报价后，接受了最低的报价。 来自《简明英汉词典》
- He must be responsible to me for this matter.这件事他必须对我负责。
- The police are responsible for the preservation of law and order.警察负责维持法律与秩序。