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
2024-04-09
51
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/3547168.html
相关试题推荐
[originaltext]Thosewhousesolarenergyhelpussaveourpreciousfuel.As
[originaltext]Thosewhousesolarenergyhelpussaveourpreciousfuel.As
[originaltext]Thosewhousesolarenergyhelpussaveourpreciousfuel.As
[originaltext]Formostpeople,readinganewspaperhasbecomeahabitpasse
[originaltext]Formostpeople,readinganewspaperhasbecomeahabitpasse
[originaltext]Theadvantagesanddisadvantagesofalargepopulationhavel
[originaltext]Theadvantagesanddisadvantagesofalargepopulationhavel
[originaltext]W:Iwasworkingonapaperaboutthedifferencesbetweenwomena
[originaltext]W:Areyougoingtothedinnerforyoungteacherstomorrownight?
[originaltext]W:Areyougoingtothedinnerforyoungteacherstomorrownight?
随机试题
FromNeolithicpotterytothe20thcenturyposters,theextantvarietiesofarts
Youmustinsistthatstudentsgiveatruthfulanswer_____withtherealityoft
高密度脂蛋白胆固醇测定的参考方法是A.肝素-Mn2+沉淀法B.磷钨酸钠一Mg2+
下列测试指标中,属于光纤指标的是(请作答此空),仪器()可在光纤的一端测得光纤
重庆市航道总里程达到()千米,“一干两支”、通江达海的航道体系基本建成。A.4
《义务教育语文课程标准)(2011版)对语法修辞知识教学有哪些实施建议
图示结构在C点作用一水平力P,其大小等于300kN。设AC杆与铅直线的夹角为α,
企业进行薪酬调整的依据一般包括()A.员工的绩效改善 B.生活成本变动 C.
函数在x点的导数是:
企业报核时,应提交哪些材料( )A.企业合同核销申请表 B.加工贸易手册 C
最新回复
(
0
)