首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Scientists say there has been a severe decrease in the amount of water in Lake Chad in northern Africa in the last thirty years.
Scientists say there has been a severe decrease in the amount of water in Lake Chad in northern Africa in the last thirty years.
admin
2007-01-12
37
问题
Scientists say there has been a severe decrease in the amount of water in Lake Chad in northern Africa in the last thirty years. They reported that nature and humans share equal blame for this loss.
In 1963, the fresh-water lake covered 25, 000 square kilometers. Now the lake is only about five percent of that size. It measures only about 1, 300 square kilometers in the dry season.
Four nations surround Lake Chad. People in Niger, Nigeria, Chad, and Cameroon use it for water, fish and plant life.
Michael Coe and Jonathan Foley, water experts at the University of Wisconsin in Madison, reported on Lake Chad in a science journal. They say the area has 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 systems further decrease the amount of lake water.
Mr. 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 provide a healthy environment for fish and plant life.
The researchers used a computer to study what caused the water loss. Their computer study estimated the climate and amount of water in the area. The estimate started with written records from the early 1960s. Then the researchers compared the estimates 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 1980s. At the time, the lake got smaller much faster than the computer research had estimated.
The researchers say that major irrigation systems were built in the 1980s. 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 that the increased irrigation reduced the flow in the two rivers. Climate changes also were responsible for the reduction. The flow of the two rivers was reduced by almost seventy-five percent.
Scientists say the problem is expected to worsen in the coming years as the population and demand for water continued to increase.
The amount of water in Lake Chad is______.
选项
答案
decreasing
解析
(文章第一段开头指出Scientists say there has been a severe decrease in the amount of water in Lake Chad.“科学家说乍得湖的水位严重下降”。)
转载请注明原文地址:https://kaotiyun.com/show/wukK777K
本试题收录于:
D类竞赛(专科)题库大学生英语竞赛(NECCS)分类
0
D类竞赛(专科)
大学生英语竞赛(NECCS)
相关试题推荐
VideoGameAddiction1.AglobalandseriousproblemAddictionoccurmorelikelyat【T1】【T1】______【T2】ofvideogamersaddicted【T
Thefinancialproblemaswellasotherissues______goingtobediscussedwhenthecongressisinsessionagainnextspring.
Yourwaystosolvethisproblem,_______,seemprettyeffective.
It’squitelatenowandMr.White_____hasn’tlefthisoffice.
Thereisanunquestionablelinkbetweenjoblossesand______services.
Areenvironmentalproblemstoobigforindividualstosolve?Thismatterhasbeenintenselydiscussedforyears.Thefollowinga
Sleep1.Howmuchsleepdoweneed■Recommendedamountforadults:【T1】______hours【T1】______2.Waysforabetterni
Lucy______goingbacktoschoolsinceshesavedenoughmoney,butshehasn’tdecidedyet.
On-campusHousingHousingpoliciesdifferfromschooltoschoolinAmericanuniversities./Someschoolshavelimitedhou
Themethodofwritingcalled"streamofconsciousness"isusedtodescribethe________ofthoughtspassingthroughthemind.
随机试题
常用的准直器的结构是
某一放大电路在负载开路时的输出电压为6V,当接人2kΩ的负载后,输出电压为4V,该放大电路的输出电阻是()kΩ。
埋地输油气管道与其他管道交叉敷设时,二者净空间距应不小于()m,且后建工程应从先建工程下方穿过。
排列图法是利用排列图寻找影响质量主次因素的一种有效方法。实际应用中,通常按累计频率划分为三部分,与其对应的影响因素分别为A、B、C三类,其中A类是指()。
2012年2月1日,新世纪以来指导“三农”工作的第9个中央一号文件()由新华社授权发布。
一、注意事项1.本次申论考试分题本和答题纸两部分。题本提供有关资料及问题,答题纸供你作答时使用。2.考生姓名、准考证号务必填写在答题纸密封线内指定位置,答题纸上不准做与答题无关的标记符号。注意:所有作答都必须填写在答题纸指定位置上,否则无效。3.用蓝
数据字典是对数据定义信息的集合,它所定义的对象都包含于______。
LookatthestatementsbelowandthefiveextractsfromnewspaperarticlesaboutChineseCPIfiguresinfivemonthsontheoppos
______heworkshard,Idon’tfindwhenhefinishestheexperiment.
Duringrecentyearswehaveheardmuchabout"race":howthisracedoescertainthingsandthatracebelievescertainthingsand
最新回复
(
0
)