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
46
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/2913501.html
相关试题推荐
[originaltext](9-1)ArecentInternationalLaborOrganizationreportsaysthe
[originaltext](9-1)ArecentInternationalLaborOrganizationreportsaysthe
[originaltext](9-1)ArecentInternationalLaborOrganizationreportsaysthe
[originaltext]ResearchershavefoundnotjustadiversityprobleminHollywo
[originaltext]ResearchershavefoundnotjustadiversityprobleminHollywo
[originaltext]Areportonsleepandnutritionreleasedthismonthfoundthat
[originaltext]Areportonsleepandnutritionreleasedthismonthfoundthat
[originaltext]ResearchershavefoundnotjustadiversityprobleminHollywo
[originaltext]ResearchershavefoundnotjustadiversityprobleminHollywo
[originaltext]M:(5)Yousayyourshophasbeendoingwell.Couldyougivemesom
随机试题
[originaltext]M:Hi,Cindy.W:Hello,John.M:DidyouenjoyBob’spartytheot
下列关于施工过程质量验收不合格处理描述错误的是()。A.在检验批验收时,发现存
我国推行的“四、二、一”保健制度是指A.生后第1年保健4次,第2年保健2次,第3
绝大多数鼻咽癌属于A.低分化腺癌 B.高分化腺癌 C.高分化鳞癌 D.低分
男,50岁,右肾下极多发结石,左输尿管上段结石直径1.5cm。IVP示右肾下极重
佛教三方佛(横三世佛)指的是()A.药师佛 B.释迦牟尼佛 C.燃灯佛 D
不是固体废弃物的主要处置方法的是()。 A填埋 B生物降解 C向他
在质量检验中,当采取查验原始质量凭证的方式时,要在()方面进行确认。 A.实
图所示的框架为某框架—剪力墙结构中的一榀边框架,其抗震等级为二级,底部一、二层顶
(2016年真题)关于钻孔灌注桩水下混凝土灌注的说法,正确的有()。A.灌注
最新回复
(
0
)