首页
登录
职称英语
[originaltext] Today, I’d like to talk about some of the changes land can und
[originaltext] Today, I’d like to talk about some of the changes land can und
游客
2024-04-02
17
管理
问题
Today, I’d like to talk about some of the changes land can undergo, specifically desertification, that’s the process through which land becomes part of a desert. Now a desert is defined as a place that receives a certain maximum amount of rainfall. But you may not know that it usually takes more than just a lack of water to turn productive land into a desert. There are several specific human activities that when combined with a lack of rainfall encourages desertification. For example, over cultivation, growing more crops than soil can support. The soil loses its nutrients, so it needs either to be fertilized or to be left unused for at least a season. But if neither of these things happens, if these nutrients in the soil don’ t get replaced, the damaged soil stops producing. Another cause of desertification is overgrazing. That’s when the grasses and trees and shrubs of an area are expected to feed more animals than they reasonably can. Too many animals eating in the same area will kill the vegetation. And because it’s the roots of this vegetation that hold much of the soil together, when too much of the vegetation dies, the soil erodes. But maybe the most ironic example of human behavior that can lead to desertification is irrigation. It may seem to run counter to common sense to say that introducing water into an area can cause it to become more like a desert But there are plenty of bad irrigation practices that do just that Bringing in too much salty water and then not providing adequate drainage for it will fill the soil with salt, and turn the area into a desert.
Now listen to the following recording and answer questions 16 to 19.
16. How is the soil damaged by over cultivation?
17. What is overgrazing?
18. How does overgrazing damage soil?
19. According to the speaker, what is the main problem with irrigation?
选项
A、The animals overfertilize the soil.
B、Dead plant roots can’t hold the soil together.
C、The wrong types of plants are left standing.
D、There is a buildup of plant and animal matter.
答案
B
解析
细节题。根据Too many animals eating in the same area will kill the vegetation.And because it’s the roots of this vegetation that hold much of the soil together, when too much of the vegetation dies, the soil erodes.可知,过度放牧会严重破坏植被,而这些植被的根能够凝沙固土,一旦植被被破坏,土地就会退化。因此,正确答案是B。
转载请注明原文地址:https://tihaiku.com/zcyy/3537465.html
相关试题推荐
Amassivepoolofwarmoceanwateriscausingchangesintheatmospherethat
Amassivepoolofwarmoceanwateriscausingchangesintheatmospherethat
[originaltext]M:[23]Somedecadesagomymotherwasreplacedbyacomputer.Her
[originaltext]M:[23]Somedecadesagomymotherwasreplacedbyacomputer.Her
[originaltext][19]Iamhonoredtobewithyoutodayatyourcommencementf
[originaltext][19]Iamhonoredtobewithyoutodayatyourcommencementf
[originaltext][19]Iamhonoredtobewithyoutodayatyourcommencementf
[originaltext][16]LeonardBernsteinsaidthattoachievegreatthings,you
[originaltext]Theworld’ssmartestadolescentsinmathematicsandsciencea
[originaltext]Weallscreamforwaterwhenthirsty.[9]Butdoyouknowinv
随机试题
ThemadnessexhibitedduringtheChristmaswas______oftheovercommercializat
WhichisNOTmentionedasthereasonwhywomenarepooratpublicspeaking?[ori
A.solidB.madeupofC.equalD.fillsE.describingF.vaporG.there
采用IE浏览器访问清华大学校园网主页时,正确的地址格式为( )。A.smtp:
2013年3月,人身险的三个险种保费收入环比增速排序正确的是:A.人身意
在合同成立前,投保人和保险人分别承担( )。 A.告知义务,告知义务
银行承兑汇票的承兑银行,应当按照票面金额向出票人收取()的手续费。A:千分之一
(2017年真题)根据《标准施工合同》,合同协议书中除明确规定合同组成文件外,双
某酒店综合改造工程,需要从2层顶板布设工字钢梁用于搭设悬挑式钢管扣件脚手架,施工
对青春期功血的治疗不包括以不哪项 A.全身支持疗法 B.促排卵治疗 C.
最新回复
(
0
)