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
2023-08-10
32
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/2913499.html
相关试题推荐
Amassivepoolofwarmoceanwateriscausingchangesintheatmospherethat
Amassivepoolofwarmoceanwateriscausingchangesintheatmospherethat
[originaltext]M:[23]Somedecadesagomymotherwasreplacedbyacomputer.Her
[originaltext][19]Iamhonoredtobewithyoutodayatyourcommencementf
[originaltext][19]Iamhonoredtobewithyoutodayatyourcommencementf
[originaltext][19]Iamhonoredtobewithyoutodayatyourcommencementf
[originaltext][16]LeonardBernsteinsaidthattoachievegreatthings,you
[originaltext][16]LeonardBernsteinsaidthattoachievegreatthings,you
[originaltext]Theworld’ssmartestadolescentsinmathematicsandsciencea
[originaltext]Theworld’ssmartestadolescentsinmathematicsandsciencea
随机试题
[originaltext]Theestimatedone-fifthofchildreninLondon’sschoolswhoc
关于锥隐窝描述有误的是()A.以上均对 B.位于后鼓室 C.在锥
A.枳实B.川楝子C.青皮D.香附E.木香善治胃肠积滞,脏器下垂的药是
选择器官移植受者的首位标准是()A.移植的禁忌证与适应证 B.受者未
晚期产后出血多发生在产后A:24小时 B:48小时 C:1~2周 D:2~
绩效考核方法中,把评级量表法与关键事件记录法结合起来,取二者之所长的方法是(
参与式培训方法使培训者与培训对象双方互动学习,具体包括()。A.案例研究法
某部件加工时,设计尺寸(单位为mm)为Tu=35.000,Tl=34.990。通
张某在某手机店购得手机,手机店承诺手机七天无理由退货。张某将手机借给朋友许某使用
患者男,41岁。上腹疼痛7小时。伴发热,体温38.5℃,频繁呕吐。查体发现上腹部
最新回复
(
0
)