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
How deserts are formed A. A desert refers to a barren section of land, mainly in arid and semi-arid areas, where there is al
How deserts are formed A. A desert refers to a barren section of land, mainly in arid and semi-arid areas, where there is al
admin
2022-01-29
67
问题
How deserts are formed
A. A desert refers to a barren section of land, mainly in arid and semi-arid areas, where there is almost no precipitation, and the environment is hostile for any creature to inhabit. Deserts have been classified in a number of ways, generally combining total precipitation, how many days the rainfall occurs, temperature, humidity, and sometimes additional factors. In some places, deserts have clear boundaries marked by rivers, mountains or other landforms, while in other places, there are no clear-cut borders between desert and other landscape features.
B. In arid areas where there is not any covering of vegetation protecting the land, sand and dust storms will frequently take place. This phenomenon often occurs along the desert margins instead of within the deserts, where there are already no finer materials left. When a steady wind starts to blow, fine particles on the open ground will begin vibrating. As the wind picks up, some of the particles are lifted into the air. When they fall onto the ground, they hit other particles which will then be jerked into the air in their turn, initiating a chain reaction.
C. There has been a tremendous deal of publicity on how severe desertification can be, but the academic circle has never agreed on the causes of desertification. A common misunderstanding is that a shortage of precipitation causes the desertification—even the land in some barren areas will soon recover after the rain falls. In fact, more often than not, human activities are responsible for desertification. It might be true that the explosion in world population, especially in developing countries, is the primary cause of soil degradation and desertification. Since the population has become denser, the cultivation of crops has gone into progressively drier areas. It’s especially possible for these regions to go through periods of severe drought, which explains why crop failures are common. The raising of most crops requires the natural vegetation cover to be removed first; when crop failures occur, extensive tracts of land are devoid of a plant cover and thus susceptible to wind and water erosion. All through the 1990s, dryland areas went through a population growth of 18.5 per cent, mostly in severely impoverished developing countries.
D. Livestock farming in semi-arid areas accelerates the erosion of soil and becomes one of the reasons for advancing desertification. In such areas where the vegetation is dominated by grasses, the breeding of livestock is a major economic activity. Grasses are necessary for anchoring barren topsoil in a dryland area. When a specific field is used to graze an excessive herd, it will experience a loss in vegetation coverage, and the soil will be trampled as well as be pulverised, leaving the topsoil exposed to destructive erosion elements such as winds and unexpected thunderstorms. For centuries, nomads have grazed their flocks and herds to any place where pasture can be found, and oases have offered chances for a more settled way of living. For some nomads, wherever they move to, the desert follows.
E. Trees are of great importance when it comes to maintaining topsoil and slowing down the wind speed. In many Asian countries, firewood is the chief fuel used for cooking and heating, which has caused uncontrolled clear-cutting of forests in dryland ecosystems. When too many trees are cut down, windstorms and dust storms tend to occur.
F. What’s worse, even political conflicts and wars can also contribute to desertification. To escape from the invading enemies, the refugees will move altogether into some of the most vulnerable ecosystems on the planet. They bring along their cultivation traditions, which might not be the right kind of practice for their new settlement.
G. In the 20th century, one of the states of America had a large section of farmland that had turned into desert. Since then, actions have been enforced so that such a phenomenon of desertification will not happen again. To avoid the reoccurring of desertification, people shall find other livelihoods which do not rely on traditional land uses, are not as demanding on local land and natural resource, but can still generate viable income. Such livelihoods include but are not limited to dryland aquaculture for the raising of fish, crustaceans and industrial compounds derived from microalgae, greenhouse agriculture, and activities that are related to tourism. Another way to prevent the reoccurring of desertification is bringing about economic prospects in the city centres of drylands and places outside drylands. Changing the general economic and institutional structures that generate new chances for people to support themselves would alleviate the current pressures accompanying the desertification processes.
H. In nowadays society, new technologies are serving as a method to resolve the problems brought by desertification. Satellites have been utilised to investigate the influence that people and livestock have on our planet Earth. Nevertheless, it doesn’t mean that alternative technologies are not needed to help with the problems and process of desertification.
Reading Passage has eight paragraphs, A-H.
Which paragraph contains the following information?
Write the correct letter, A-H, in boxes on your answer sheet.
NB You may use any letter more than once.
lack of agreement among the scientists about the causes of desertification
选项
答案
C
解析
科学家们对沙漠化的成因缺乏一致意见。关键词causes of desertification、scientists、 lack of agreement。C段开头第1句先是说沙漠化的严重性已经得到了大量宣传,紧接着but转折后的内容为该句的主要意思,即学术界就沙漠化的成因从未达成一致意见。其中本题题干的关键词causes of desertification原文重现,原文the academic circle has never agreed对应题干lack of agreement among the scientists。因此,本题的正确答案为C。
转载请注明原文地址:https://kaotiyun.com/show/TBAO777K
本试题收录于:
雅思阅读题库雅思(IELTS)分类
0
雅思阅读
雅思(IELTS)
相关试题推荐
Althoughthescientist’srecommendationsmayhavebeen______,thestudentshadtroublefollowinghis______presentationandw
ThispassageisadaptedfromTheAmericanRepublic:Constitution,Tendencies,andDestinybyO.A.Brownson,1866.Thean
ThepolarlightsknownasaurorasareproducedwhenchargedsubatomicLineparticles,suchasprotonsandelectronsflowingfro
Educatorswhostudytheinfluencesofgeographicaldifferencesoneducationalsuccesshaveconcludedthatenvironmentisnot___
Ashasalwaysbeenthecasewhentragedyhasstruckourcommunity,thepeopleofourtownfeeltheobligation,andrightlyso,t
WhetherthelanguagesoftheancientAmericanpeopleswereusedforexpressingabstractuniversalconceptscanbeclearlyanswer
Thispassageisadaptedfrommaterialpublishedin2001.FrederickDouglasswasunquestionablythemostfamousAfricanAmerican
PopularinterestinmusicperformedbyfolksingerJeanRitchieactedasa(i)______becauseit(ii)______awiderinterestinth
Scientistsreportedlastmonthonasignofrelativesolar_______:thesolarwind,arushofchargedparticlescontinuallyspewe
Anypopulationincreasebeyondacertainlevelnecessitatesgreater(i)________vegetablefoods;thus,theabilityofasociety
随机试题
下列做法中,能够提高财政自身管理和运营效率的有()。
民事诉讼中,当事人不服地方人民法院第一审裁定的,有权在裁定书送达之日起()向上一级人民法院提起上诉。
实验室检查证实单纯疱疹病毒性角膜炎的金标准是
下列有关系统性硬化症的说法,哪一项是错误的
目标评价的常用分析方法包括目标树法、层次分析法等,国际上通常采用()。
案例五:张鹏和李平是同在北京工作的好友,两家居住在同一个居民楼。目前两家都打算额外购置一处房产,价格在50万元左右。张鹏夫妇皆为公务员,每月都按时缴纳住房公积金,张鹏的太太预计在退休年龄内可缴存住房公积金15万元,张鹏离法定退休年龄还剩30年,其名下现有的
为提高闲置资金的使用率,甲公司20×8年度进行了以下投资:(2009年)(1)1月1日,购入乙公司于当日归行且可上市交易的债券100万张,支付价款9500万元,另支付手续费90.12万元。该债券期限为5年,每张面值为100元,票面年利率为6%,于每年12
根据下面材料回答问题。2013年某省全部工业增加值13194.8亿元,比上年增长9.4%。规模以上工业增加值11711.1亿元,增长5.8%。在规模以上工业中,国有及国有控股企业增加值增长3.2%,集体企业下降0.2%.股份制企业增长11.2%,外商及港
FTP命令集因系统、版本而异,常用的命令如下。(54)有ASCII和二进制模式。(55)改变计算机的当前目录。(56)open建立同远程计算机的连接,close关闭连接。(57)put传送一个文件到远程计算机,put传送多个文件到远程计算机。(58)get
Mr.Smith,apassengeronthetranscontinentaltrain,appearedbeforethejudge.Apoliceofficerclaimedhehadattemptedto【
最新回复
(
0
)