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
2024-08-18
34
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/3725287.html
相关试题推荐
ScientistssaytherehasbeenaseveredecreaseintheamountofwaterinLa
ScientistssaytherehasbeenaseveredecreaseintheamountofwaterinLa
ScientistssaytherehasbeenaseveredecreaseintheamountofwaterinLa
Theconceptoftelevision,______imagesoverdistances,hadintriguedscientists
Scientistshavedevelopedapioneeringtechnologythatallowschildrenwith
Scientistshavedevelopedapioneeringtechnologythatallowschildrenwith
Scientistsknowthattherearetwobasicapproachestoprolongingforlife.
Scientistsknowthattherearetwobasicapproachestoprolongingforlife.
Scientistsknowthattherearetwobasicapproachestoprolongingforlife.
Scientistsknowthattherearetwobasicapproachestoprolongingforlife.
随机试题
PASSAGEONEToenhanceanimals’mentalhealth.由题干中的traditionalenrichingmeasures定
WritingBasedonKnowledgeandExperienceDirections:Forthistask,
Afour-yearstudybysociologistsatTheUniversityofManchesterhasfound
希格拉德拉塞丽娜镇像是西班牙危机的一个缩影。由于很多耗资巨大的工程超支,很多小镇都面临和西班牙国家和地区政府同样的问题。【T1】但是由于当地的居民在政府支
《秦王点兵》动作结构的来源是()。A.奥迪西 B.僧舞 C.芭蕾 D.华
治疗正疟,应首选( )。A.柴胡截疟饮 B.白虎加桂枝汤 C.柴胡桂枝干姜
某窗口只有张、王、李、赵、宋5个同学站成一列在排队,已知: (1)王和李两人紧
企业在制定自己的工资政策、确定企业工资水平时,必须要对()有正确的了解。A.货
根据《国家发展改革委委托咨询评估管理办法》,咨询评估机构的下列情形中,可能导致其
复杂分解爆炸类可爆物的危险性较简单分解爆炸物稍低,其爆炸时伴有燃烧现象,燃烧所需
最新回复
(
0
)