首页
登录
职称英语
[originaltext] Today, I’d like to talk about some of the changes land can un
[originaltext] Today, I’d like to talk about some of the changes land can un
游客
2023-08-16
39
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/2930910.html
相关试题推荐
[originaltext]Manyareasaroundtheworldsufferfromfrequentlossofelec
[originaltext]Manyareasaroundtheworldsufferfromfrequentlossofelec
[originaltext]W:Asinglecigarettesoldonastreetcornermaynotcostalot;
[originaltext]IfyouareinterestedinstudyingatanAmericanuniversity,
[originaltext]IfyouareinterestedinstudyingatanAmericanuniversity,
[originaltext]Cleanairisimportanttogoodhealth.Iftheaircontainsim
[originaltext][9]VisitorstoBritainaresometimessurprisedtolearnthat
[originaltext][9]VisitorstoBritainaresometimessurprisedtolearnthat
[originaltext]W:[5]ProfessorSmith,Iwonderifyoucanfillmeinonyourlec
[originaltext]W:[5]ProfessorSmith,Iwonderifyoucanfillmeinonyourlec
随机试题
HowmanyofficersdoestheHongKongPolicedepartmentroughlyhaveaccordingto
函数不可导点的个数是().A.3 B.2 C.1 D.0
利润中心一般用一张()来呈现其业绩。A.资产负债表 B.现金流量表 C.内部
确定空调房间围护结构的传热系数时,需要考虑的因素有()。A.室内外温差、恒温
下列关于建筑材料分类说法错误的是()。A.按照化学成分来分类,水泥混凝土属
秦始皇统一中国的时间是( )。A.公元前230年 B.公元前228年 C.公
写字楼物业的市场营销,不宜采取的操作方式是()。A:围绕物业的交通便利性展开市场
基金合同是约定基金管理人、基金托管人和基金份额持有人权利义务关系的重要法律文件,
下列化合物属于黄酮醇的是A.大豆素 B.葛根素 C.橙皮苷 D.山奈酚
路基处理方法中:重锤夯实、机械碾压、振动压实、强夯的方法属于( )。A.换土垫层
最新回复
(
0
)