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
2024-03-13
16
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、It can cause flooding
B、It can carry diseases that affect animals.
C、It can introduce too much salt into the soil.
D、It can divert water from important crops.
答案
C
解析
细节题。根据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可知灌溉含盐的水,且没有引流,也会导致土地沙漠化。因此,正确答案是C。
转载请注明原文地址:https://tihaiku.com/zcyy/3529762.html
相关试题推荐
[originaltext]Whenwethinkofgames,thereareallkindsofthings.Maybeyou’
[originaltext]Whenwethinkofgames,thereareallkindsofthings.Maybeyou’
[originaltext]MyfellowSingaporeans:Whatwereyourmostmemorablemoments
[originaltext]MyfellowSingaporeans:Whatwereyourmostmemorablemoments
[originaltext]AbeetleinvasionintheUnitedStateshaskilledatleasttwenty
[originaltext]AbeetleinvasionintheUnitedStateshaskilledatleasttwenty
[originaltext]AbeetleinvasionintheUnitedStateshaskilledatleasttwenty
[originaltext][12]Intoday’spersonalitystakes,nothingismorehighlyvalued
[originaltext]Pianosarenormallyfoundinbuildingforobviousreasons.Howeve
[originaltext]W:Hello.M:Hello,isthatthereferencelibrary?W:Yes.CanI
随机试题
A.patrollingB.permissionC.accusationD.insufficientE.nightmareF
WhathappenedinAlgeriaTuesday?_____[br]Howmanypeoplewerekilledinthe
[originaltext]AtsixteenHenryVincentwasseparatedfromhisfamilyasar
光阴的故事 春天的花开秋天的风以及冬天的落阳 忧郁的青春年少的我曾经无知地那
浮充电为将充电电路和储能元件的供电电路并联接到负载上,充电电路在向负载供电的同时
对税收的内涵理解正确的有( )。A.国家征税的目的是满足社会成员获得公共产品的
化脓性关节炎的早期表现中,错误的是:A.关节处疼痛,轻微活动即引起剧痛 B.
患者,男,46岁,因足底刺伤后出现全身肌肉强直性收缩,阵发性痉挛,诊断为破伤风。
下列个人转让住房行为中,免征个人所得税的是( )。A.转让已购公有住房 B.
下列参数中,不属于风机性能参数的是()。A.风量 B.风速 C.全风压
最新回复
(
0
)