首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
专升本
The forest from which Man takes his timber is the tallest and most impressive plant community on Earth. In terms of Man’s brief
The forest from which Man takes his timber is the tallest and most impressive plant community on Earth. In terms of Man’s brief
admin
2016-03-05
23
问题
The forest from which Man takes his timber is the tallest and most impressive plant community on Earth. In terms of Man’s brief life it appears permanent and unchanging, save for the seasonal growth and fall of the leaves, but to forester it represents the climax of a long succession of events.
No wooded landscape we see today has been forest for all time. Plants have minimum requirements of temperature and moisture and, in ages past, virtually every part of Earth’s surface has at some time been either too dry or too cold for plants to survive.
However, as soon as climatic conditions change in favour of plant life, a fascinating sequence of changes occurs, called a
primary succession
. First to colonize the barren land are the lowly lichens(地衣), surviving on bare rock. Slowly, the acids produced by these organisms crack the rock surface, plant debris accumulates, and mosses(苔藓)establish a shallow root-hold. Ferns(蕨类植物)may follow and, with short grasses and shrubs, gradually form a covering of plant life. Roots probe even deeper into the developing soil and eventually large shrubs give way to the first trees. These grow rapidly, cutting off sunlight from the smaller plants, and soon establish complete domination—closing their ranks and forming a climax community which may endure for thousands of years.
Yet even this community is not everlasting. Fire may destroy it outright and settlers may cut it down to gain land for pasture or cultivation. If the land is then abandoned, a
secondary succession
will take over, developing much faster on the more hospitable soil. Shrubs and trees are among the early invaders, their seeds carried by the wind, by birds and coats of mammals.
For as long as it stands and thrives, the forest is a vast machine, storing energy and many elements essential for life.
In a "primary succession" , what makes it possible for mosses to take root?
选项
A、The type of rock.
B、The amount of sunlight.
C、The amount of moisture.
D、The effect of lichens.
答案
D
解析
“在‘初级演替’中,什么使苔藓生根成为可能?”本题为一般阅读理解题,第三段的第二句话中,作者提到了首先能在岩石上生存的植物是lichen(地衣),然后在地衣生长之后,由于地衣的影响才能使moss(苔藓)的生长成为可能。
转载请注明原文地址:https://kaotiyun.com/show/JTHC777K
本试题收录于:
英语题库普高专升本分类
0
英语
普高专升本
相关试题推荐
Aweddingiscelebratedwithsomekindofceremonyalmosteverywhereintheworld.Theceremonyisdifferentamongdifferentnat
Everysporthasitsgreatlegends:soccerhasPele,andbasketballhasMichaelJordan.Isthereone【B1】______whompeopleconside
Mysonhasstartedtohangoutwiththewrongtypeofboys.HeisfifteenyearsoldanduntilrecentlyIhadalwaysbeengratefu
Mysonhasstartedtohangoutwiththewrongtypeofboys.HeisfifteenyearsoldanduntilrecentlyIhadalwaysbeengratefu
—HI,Mary,Iheardyougetaheavyheadache.Howareyoufeelingtoday?—Thanks!【D1】______—Youshouldhaveagoodrest.—【D2
—I’msorryforhavingtroubledyouwithsomanyquestions.—______
A、taughtB、caughtC、daughterD、laughD
Mostyoungpeopleenjoyphysicalactivities,walking,cycling,football,ormountaineering.Thesewhohaveapassion【C1】____
Forthispart,youareallowed30minutestowriteanessayentitledShouldCollegeGraduatesGetPaidMorethanNon-grads?You
It’sagreatpitythatthegirl______halfwayanddroppedoutofthecompetition.
随机试题
在文件系统中,文件的不同物理结构有不同的优缺点。在下列文件的物理组织结构中,不具有直接读写文件任意一个记录的能力的结构是()。
通过应聘者对某些问题的回答,测试其思维能力、记忆能力、应变能力和观察分析复杂问题的能力是______。
《土地法》规定“(),可以依法确定给单位或者个人使用。使用土地的单位和个人,有保护、管理和合理利用土地的义务”。
设备监理目标的( )是指对于任何一个具体的设备工程项目,尽管需要协调各个目标之间的关系,但往往是以某一目标为主要目标的。
对当事人作出罚款决定的,当事人到期不缴纳罚款,作出行政处罚的通信主管部门可以依法从到期之次日起,每日按罚款数额的()加处罚款。
聊斋志异:蒲松龄
债权人领取提存物的期限是自提存之日起()
在中美两国政府的共同支持下,美国的学校开始在语言教学大纲巾增设汉语——这个世界上使用人数多但同时也是最难学的语言之一。在2400所学校表示有兴趣之后,将于明年开始在全国范围内的中学开设汉语高级分级课程。因此全美国范围内的汉语语言课程,包括小学到成人教育,在
Anotherculturalaspectofnonverbalcommunicationisonethatyoumightnotthinkabout:space.Everyperson【B1】______himself
A、Hecanofferamuchcheaperpriceforthiscar.B、Hisannualsavingsarequiteenoughtobuythiscar.C、Thiscarneedslessp
最新回复
(
0
)