首页
登录
职称英语
Scientists say there has been a severe decrease in the amount of water in La
Scientists say there has been a severe decrease in the amount of water in La
游客
2023-10-19
79
管理
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. 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. [br] The change in the size of Lake Chad is caused by the climate, ______ and ______.
选项
答案
irrigation, increased population
解析
转载请注明原文地址:https://tihaiku.com/zcyy/3110717.html
相关试题推荐
(1)Therehasbeenafairamountinthenewslatelyaboutapologies,particu
(1)Therehasbeenafairamountinthenewslatelyaboutapologies,particu
Agreatamountofworkhasgoneinto________theCathedraltoitsprevioussplend
Usuallythereisa________increaseintheamountofmailduringtheChristmasse
Withage,themineralcontentofhumanbonesdecreases,________themmorefragil
Therehavealwaysbeenreputableandcompetentscientistswhohavedisagreedwit
________thatthepilotcouldn’tflythroughit.A、ThestormsoseverewasB、Sose
Scientistshaveknownhowtoharnessthelimitlesspowerofthesun.Theunderli
Theworld’sleadingclimatescientistshavesetoutindetailforthefirst
ScientistssaytherehasbeenaseveredecreaseintheamountofwaterinLa
随机试题
HowtoAssessaGraduateSchoolGeneralcriteriatofollowincho
[originaltext]W:Oh,whatanuisance!M:Hey,Julia.What’sthematter?Youdon
Theriseofmultinationalcorporations(跨国公司),globalmarketing,newcommuni
未决赔款准备金是指保险人对在保险有效期内发生的未决赔款从当期保费收入中提存的资金
下列医德基本原则不包括:A.尊重原则 B.不伤害原则 C.有利原则 D.公
引起白蛋白/球蛋白(A/G)降低的疾病是()A.肾上腺皮质功能减退症
按照现行规定,工程建设过程中建设单位扣留每期工程进度款的( )作为工程质量保证金
4个杯子上各写著一句话,第一个杯子:每个杯子中都是酸性溶液,第二个杯子:本杯中是
()对出勤率没有苛刻的要求。A.推销员 B.门岗门卫 C.经理 D.后台
人在每一瞬间,将心理活动选择了某些对象而忽略了另一些对象。这一特点指的是注意的(
最新回复
(
0
)