Pedodiversity Plant托福聽(tīng)力原文翻譯及問(wèn)題答案

Pedodiversity Plant托福聽(tīng)力原文翻譯及問(wèn)題答案

一、Pedodiversity Plant托福聽(tīng)力原文：

NARRATOR:Listen to part of a lecture in a plant ecology class.FEMALE PROFESSOR:So far we have covered biodiversity in the hard wood forest here in the upper peninsula of Michigan from a number of angles.We've looked at everything from how biodiversity relates to species stability,to competition for forests resources and more.

But now I want to discuss what's called pedodiversity.Pedodiversity is basically soil diversity.When we analyze pedodiversity within an area,we are measuring how much variability there is in soil properties and how many different types of soil there are in a particular area.

So we look at soil chemistry.For example,how much nitrogen or magnesium there's in the soil in one spot.And we compare it with the chemistry of the soil a short distance away.Until recently,there hasn't been a whole lot of attention paid to pedodiversity.But that's changing rapidly.More and more studies are being done in these fields.There's a link between biodiversity and pedodiversity,an obvious relationship between soils and flora and fauna,which is why pedodiversity really should be considered in forest management.A high degree of soil variability in a small area is common,particularly within forests.If you compare soils from a forest with soils that don't come from a forest,the amount of variability will most likely be greater in the forest's soil.It generally has more diversity.Um,OK.There are three main causes of pedodiversity within old-growth forest here in our region of Michigan.One is tree species.Different species have different influences on soil formation and soil properties.For example,pine trees drop pine needles.And those needles add a lot of acid to the soil.The organic litter of another tree species might add less acid but more of something else.A lot of different types of trees in an area might mean more pedodiversity.Another cause?Gaps created when trees fall.You see,where there are gaps—open areas—in the forest,the soil there changes.Um,for instance,without a tree to absorb radiation from the Sun,to offer shade,the full intensity of that radiation reaches the ground.The soil where the tree used to be heats up.And without a tree to soak up moisture from the ground,the soil remains wetter than in the surrounding forest.With a higher temperature and more moist conditions,the process of organic matter decomposition speeds up.In other words,organic matter gets broken down and added into the soil more quickly in these gaps than in the surrounding forest.OK.And the third cause:trees being uprooted.When a tree is uprooted,it might fall into some other trees on its way down,thus falling only partway over.Or it might crash all the way down to the forest floor.Either way,if its roots are pulled up from out of the ground as the tree topples over,then there's usually a big hole—a pit—left in the ground where the roots used to be.

And there's still a lot of soil attached to the roots,clinging to the roots.As that soil is eventually shed from the roots by rain and wind and the movement of squirrels climbing around,things like that.Um...as the soil is shed,it drops down and forms a little hill of dirt—a mound.Pits and mounds have significantly different soil properties than other areas in the forest.You get a redistribution and mixing of soil as deep roots are ripped up from the ground.Rock fragments can be pulled up too,if they've gotten entangled with the roots over the years.So rock fragments from the subsoil can end up concentrated on the surface.There are forests management implications I want to point out.Forests management impacts soil quality.And when we better understand pedodiversity,we will be better able to predict the impact of forest management on soil.But in general,for positive impact,forest management practices should mimic natural forest processes.And the goal should be to promote pedodiversity,and through this,biodiversity in general.I have a handout,an article on pedodiversity in a section of forests near here.I want you to read it,because it makes a point that I've only touched on.From what I have been saying about the causes of pedodiversity,you might assume that the relationship between forest dynamics,what happens to the trees,and pedodiversity is a one-way street.As the article explains,forest dynamics affects pedodiversity.But pedodiversity also affects forest dynamics.It's worth bearing in mind.

二、Pedodiversity Plant托福聽(tīng)力中文翻譯：

旁白：在植物生態(tài)學(xué)課上聽(tīng)一部分講座。女教授：到目前為止，我們已經(jīng)從多個(gè)角度涵蓋了密歇根州上半島的硬木森林的生物多樣性。我們研究了從生物多樣性與物種穩(wěn)定性的關(guān)系到森林資源的競(jìng)爭(zhēng)等等。

但現(xiàn)在我想討論什么叫兒童多樣性。土壤多樣性基本上是土壤多樣性。當(dāng)我們分析一個(gè)區(qū)域內(nèi)的土壤多樣性時(shí)，我們測(cè)量的是土壤性質(zhì)的變異程度，以及特定區(qū)域內(nèi)有多少不同類(lèi)型的土壤。

所以我們來(lái)看看土壤化學(xué)。例如，一個(gè)地點(diǎn)的土壤中有多少氮或鎂。我們將其與不遠(yuǎn)處土壤的化學(xué)性質(zhì)進(jìn)行比較。直到最近，對(duì)兒童多樣性的關(guān)注還不多。但這種情況正在迅速變化。在這些領(lǐng)域正在進(jìn)行越來(lái)越多的研究。生物多樣性和土壤多樣性之間有聯(lián)系，土壤和動(dòng)植物之間有明顯的關(guān)系，這就是為什么在森林管理中應(yīng)該考慮土壤多樣性。小面積的土壤變異性很高，特別是在森林中。如果將森林土壤與非森林土壤進(jìn)行比較，則森林土壤的變異性可能更大。它通常具有更多的多樣性。嗯，好的。在我們密歇根州的老森林中，有三個(gè)主要原因?qū)е铝送寥蓝鄻有?。一是?shù)種。不同物種對(duì)土壤形成和土壤性質(zhì)的影響不同。例如，松樹(shù)掉落松針。這些針頭給土壤添加了大量的酸。其他樹(shù)種的有機(jī)垃圾可能會(huì)添加更少的酸，但會(huì)添加更多的其他物質(zhì)。一個(gè)地區(qū)有許多不同類(lèi)型的樹(shù)木可能意味著更多的土壤多樣性。另一個(gè)原因？樹(shù)木倒下時(shí)會(huì)產(chǎn)生空隙。你看，在森林中有空隙的地方，土壤會(huì)發(fā)生變化。嗯，比如說(shuō)，如果沒(méi)有一棵樹(shù)來(lái)吸收來(lái)自太陽(yáng)的輻射，提供陰涼，輻射的全部強(qiáng)度就會(huì)到達(dá)地面。這棵樹(shù)以前生長(zhǎng)的地方的土壤變熱了。如果沒(méi)有一棵樹(shù)從地面吸收水分，土壤比周?chē)纳指鼭駶?rùn)。隨著溫度和濕度的升高，有機(jī)物的分解過(guò)程加快。換句話說(shuō)，有機(jī)物質(zhì)在這些空隙中分解和添加到土壤中的速度比在周?chē)种懈?。好的。第三個(gè)原因：樹(shù)木被連根拔起。當(dāng)一棵樹(shù)被連根拔起時(shí)，它可能會(huì)在倒下的過(guò)程中掉到其他樹(shù)上，因此只會(huì)掉到一半?；蛘咚赡芤宦穳嬄涞缴值孛?。不管是哪種情況，如果樹(shù)倒下時(shí)，它的根被拔出地面，那么通常會(huì)有一個(gè)大洞-一個(gè)坑，在地面上留下根。

還有很多土壤附著在根部，附著在根部。由于雨水和風(fēng)以及松鼠四處攀爬的運(yùn)動(dòng)，土壤最終會(huì)從根部脫落。嗯…當(dāng)土壤脫落時(shí)，它會(huì)落下來(lái)形成一個(gè)小土丘-一個(gè)土丘?？雍屯燎鸬耐寥捞匦耘c森林中的其他區(qū)域明顯不同。當(dāng)深根從地上被撕開(kāi)時(shí)，土壤會(huì)重新分布和混合。巖石碎片也可以被拉起，如果這些年來(lái)它們與樹(shù)根糾纏在一起。因此，來(lái)自底土的巖石碎片最終會(huì)集中在地表。我想指出森林管理的影響。森林管理影響土壤質(zhì)量。當(dāng)我們更好地理解土壤多樣性時(shí)，我們將能夠更好地預(yù)測(cè)森林管理對(duì)土壤的影響。但總的來(lái)說(shuō)，為了產(chǎn)生積極影響，森林管理做法應(yīng)模仿自然森林過(guò)程。目標(biāo)應(yīng)該是促進(jìn)土壤多樣性，并通過(guò)這一點(diǎn)，促進(jìn)總體生物多樣性。我有一份講義，一篇關(guān)于附近一片森林中的土壤多樣性的文章。我想讓你們讀這篇文章，因?yàn)樗岢隽艘粋€(gè)我剛剛提到的觀點(diǎn)。從我所說(shuō)的土壤多樣性的原因來(lái)看，你可能會(huì)認(rèn)為森林動(dòng)態(tài)、樹(shù)木的變化和土壤多樣性之間的關(guān)系是單向的。正如本文所解釋的，森林動(dòng)態(tài)影響土壤多樣性。但土壤多樣性也影響森林動(dòng)態(tài)。這是值得銘記的。

三、Pedodiversity Plant托福聽(tīng)力問(wèn)題：

Q1:1.What does the professor mainly discuss?

A.Causes of soil diversity in old-growth forests

B.The results of a recent research study in a Michigan forest

C.The impact of pedodiversity on forest growth

D.How forest management affects soil diversity

Q2:2.According to the professor,in what way is the soil in forested areas generally different from soil in other areas?

A.In forested areas,the soil tends to be warmer and moister.

B.In forested areas,the chemistry of the soil changes more rapidly.

C.In forested areas,there is usually more variability in soil types.

D.In forested areas,there is generally more acid in the soil.

Q3:3.What does the professor suggest are the three main causes of pedodiversity in the old-growth hardwood forests she discusses?[Click on 3 answers.]

A.The uprooting of trees

B.The existence of gaps

C.Current forest-management practices

D.Diversity of tree species

E.Changes in climatic conditions

Q4:4.Why does the professor mention radiation from the Sun?

A.To point out why pits and mounds have soil with unusual properties

B.To indicate the reason some tree species thrive in Michigan while others do not

C.To give an example of a factor that cannot be reproduced in forest management

D.To help explain the effects of forest gaps on soil

Q5:5.Why does the professor consider pedodiversity an important field of research?

A.It has challenged fundamental ideas about plant ecology.

B.It has led to significant discoveries in other fields.

C.It has implications for forest management.

D.It is an area of study that is often misunderstood.

Q6:6.Why does the professor give the students an article to read?

A.To help them understand the relationship between forest dynamics and pedodiversity

B.To help them understand how to approach an assignment

C.To provide them with more information on pits and mounds

D.To provide them with more exposure to a controversial aspect of pedodiversity

四、Pedodiversity Plant托福聽(tīng)力答案：

A1:正確答案：A

A2:正確答案：C

A3:正確答案：ABD

A4:正確答案：D

A5:正確答案：C

A6:正確答案：A

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