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
30
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 receives more nutrients than it can absorb.
B、It becomes oversaturated with water.
C、It loses the ability to support insect life.
D、It loses nutrients that aren ’t replaced.
答案
D
解析
细节题。根据For example,over cultivation, growing more crops than soil can support.The soil loses its nutrients可知,过度耕种也就是超过土地承载力种植过多的植物,会导致土地营养流失。因此,正确答案是D。
转载请注明原文地址:https://tihaiku.com/zcyy/3529759.html
相关试题推荐
[originaltext]Whenwethinkofgames,thereareallkindsofthings.Maybeyou’
[originaltext]MyfellowSingaporeans:Whatwereyourmostmemorablemoments
[originaltext]AbeetleinvasionintheUnitedStateshaskilledatleasttwenty
[originaltext][12]Intoday’spersonalitystakes,nothingismorehighlyvalued
[originaltext][12]Intoday’spersonalitystakes,nothingismorehighlyvalued
[originaltext]Pianosarenormallyfoundinbuildingforobviousreasons.Howeve
[originaltext]Pianosarenormallyfoundinbuildingforobviousreasons.Howeve
[originaltext]W:Hello.M:Hello,isthatthereferencelibrary?W:Yes.CanI
[originaltext]W:Hello.M:Hello,isthatthereferencelibrary?W:Yes.CanI
[originaltext]W:Hello.M:Hello,isthatthereferencelibrary?W:Yes.CanI
随机试题
Itwas(luck)_______indeedforMr.Foxtohavechangedhisflightandarrived
[img]2017m2x/ct_ehbm_ehbreadf_0269_201702[/img][br]LearnItteammemberswill
Theconceptofpersonalchoiceinrelationtohealthbehaviorsisanimport
1.2millionroaddeathsworldwideoccureachyear,plusafurther50million
某信息化工程中,建设单位要求承建单位只备份上次完全备份后系统中变化过的数据信息,
某软件项目的活动图如下图所示,其中顶点表示项目里程碑,连接顶点的边表示包含的活动
藿香正气散组成中含有的药物是A.白术,陈皮 B.苍术,半夏 C.大腹皮
朱砂的炮制方法是A.米炒 B.清水煮 C.酒炙 D.煅法 E.水飞
哲学的基本问题是人们认识世界的出发点,它是指( ) A.人与自然的关系问题
转录的不对称性表现在( )。A.DNA的两条链均作为模板,转录方向相反 B.
最新回复
(
0
)