Assisted Migration Conservation托福听力原文翻译及问题答案

Assisted Migration Conservation托福听力原文翻译及问题答案

一、Assisted Migration Conservation托福听力原文：

NARRATOR:Listen to part of a lecture in a conservation biology class.FEMALE PROFESSOR:One consequence of global warming is extinction...there's compelling evidence that global warming will be a significant driver of many plant and animal extinctions in this century.So,we're considering various strategies to help some threatened species survive this unprecedented,this warming trend,which,as you know,is caused mainly by greenhouse gases produced by the burning of fossil fuels.

Um,the most radical strategy being debated among conservation biologists is"assisted migration."Assisted migration means picking up members of a species—or members of a group of interdependent species—and physically moving,or translocating them......um,translocating threatened species to a cooler place,to higher latitudes or higher elevations,for example.Now,migration's a natural survival strategy.Over the past two million years,colder glacial periods have alternated with warmer interglacial periods,and so...um,in-in response to these gradual climatic swings,some species have shifted their ranges hundreds of kilometers.

So,perhaps you're wondering:Why not let nature take its course now?Well,we can't.The main problem is today's fragmented habitats.During previous interglacial periods,when glaciers retreated,they left behind open land in their wakes.Today,human development has paved over much of the natural world.Ecosystems are fragmented.

Housing developments,highways,and cities have replaced or sliced through forests and prairies.There're few corridors left for species to migrate through—without help.So,conservationists are trying to save as many species as possible.

Now,assisted migration could become a viable part of our rescue strategy,but there are a number of uncertainties and risks.Without more research,we can't predict if assisted migration will work for any given species.A translocated species could die out from lack of food,for example.At the other extreme,we might successfully translocate a species,but within five or ten years,that species could proliferate and become an invasive species.

Like a nonnative plant that chokes out native plants by hogging the nutrients in the soil.Translocated animals can become invasive,too.It happened in Australia.The cane toad was introduced back in 1935 to control an insect pest that was destroying Australia's sugarcane plantations.But the cane toad itself became a pest and has destroyed much of the wildlife on that continent.Also,many species are interdependent,intimately connected to one another.Like animals that eat a certain plant and that plant relies on a certain fungus to help it get nutrients from soil and on a certain insect for pollination.We probably have to translocate entire networks of species and it's hard to know where to draw the line.

And in addition to all that,it is not even clear that assisted migration or any migration for that matter,will help at least for some species.Earth was already in one of its warm interglacial periods when we started burning fossil fuels.And in the twenty-first century,global temperatures are expected to rise two to six degrees.That rate of heating is far greater than during the last glacial retreat some 12,000 years ago.

Um...whether to use Assisted Migration,this debate is mostly within the biology community right now.But the ultimate decision-makers,in the United States at least,will be the government agencies that manage natural resources.Assisted Migration really needs this level of oversight,and soon.Currently there's no public policy on using assisted migration to help species survive climate change.

People aren't even required to seek permits to move plants or invertebrate animals around as long as they are not classified as pests.In one case,a group of conservationists has already taken it upon itself to try on their own to save an endangered tree,the Florida Torreya tree,through Assisted Migration.

There's only about a thousand individual Florida Torrey as left.And global warming is expected to significantly reduce or eliminate this tree's habitat.So this conservation group wants to translocate seedlings,Florida Torreya seedlings,500 kilometers north in order to expand the species'range.The group believed its effort is justified,but I and many other biologists will be watching very closely how this maverick group makes out,because,like I said,there could be unintended consequences.

二、Assisted Migration Conservation托福听力中文翻译：

旁白：听一节保护生物学课上的部分讲座。女教授：全球变暖的一个后果是灭绝……有令人信服的证据表明，全球变暖将是本世纪许多动植物灭绝的重要驱动力。因此，我们正在考虑各种策略，以帮助一些受威胁的物种在这种前所未有的变暖趋势下生存，正如你所知，这主要是由化石燃料燃烧产生的温室气体造成的。

嗯，保护生物学家正在讨论的最激进的策略是“协助迁移”。协助迁移意味着捡起一个物种的成员或一组相互依存的物种的成员，并实际移动或转移它们……嗯，将受威胁的物种转移到较冷的地方，例如，更高纬度或更高海拔地区。现在，移民是一种自然的生存策略。在过去的两百万年中，较冷的冰期与较暖的间冰期交替出现，因此…嗯，为了应对这些逐渐变化的气候，一些物种已经将活动范围移动了数百公里。

所以，也许你在想：为什么不让大自然顺其自然呢？嗯，我们不能。主要问题是今天的栖息地支离破碎。在前一次间冰期，当冰川退缩时，它们会留下开阔的土地。今天，人类发展已经覆盖了大部分自然世界。生态系统支离破碎。

住房开发、高速公路和城市已经取代或割断了森林和草原。在没有帮助的情况下，物种迁徙的通道已所剩无几。因此，自然资源保护主义者正试图拯救尽可能多的物种。

现在，协助移民可能成为我们救援战略的一个可行部分，但也存在一些不确定性和风险。如果没有更多的研究，我们无法预测辅助迁移是否适用于任何特定物种。例如，易位物种可能因缺乏食物而灭绝。在另一个极端，我们可能成功地转移一个物种，但在五年或十年内，该物种可能会繁殖并成为入侵物种。

就像一种非本土植物，它通过吞噬土壤中的营养物质来扼杀本土植物。易位的动物也会变得具有侵略性。它发生在澳大利亚。甘蔗蟾蜍早在1935年就被引进，用来控制一种正在破坏澳大利亚甘蔗种植园的害虫。但甘蔗蟾蜍本身就成了一种害虫，破坏了该大陆的许多野生动物。此外，许多物种相互依存，彼此密切相关。就像吃某种植物的动物一样，这种植物依靠某种真菌从土壤中获取养分，依靠某种昆虫授粉。我们可能不得不转移整个物种网络，很难知道在哪里划清界限。

除此之外，目前还不清楚辅助迁移或任何相关迁移是否至少对某些物种有帮助。当我们开始燃烧化石燃料时，地球已经处于温暖的间冰期。在二十一世纪，全球气温预计将上升2至6度。这一升温速率远大于12000年前的最后一次冰川消退。

嗯…是否使用辅助迁移，这场辩论目前主要在生物学界。但最终的决策者，至少在美国，将是管理自然资源的政府机构。援助移民确实需要这种程度的监督，而且很快就会实现。目前，没有关于利用协助迁徙帮助物种在气候变化中生存的公共政策。

人们甚至不需要申请许可证来移动植物或无脊椎动物，只要它们不被归类为害虫。在一个案例中，一群自然资源保护者已经主动尝试通过协助迁徙来拯救一棵濒临灭绝的树——佛罗里达香榧树。

剩下的佛罗里达托瑞只有一千只。预计全球变暖将显著减少或消除这棵树的栖息地。因此，这个保护组织想将树苗，佛罗里达香榧树苗转移到北部500公里处，以扩大该物种的范围。该小组认为其努力是合理的，但我和许多其他生物学家将密切关注这个特立独行的小组的进展，因为正如我所说的，可能会出现意想不到的后果。

三、Assisted Migration Conservation托福听力问题：

Q1:1.What is the main purpose of the lecture?

A.To explain the government’s role in the regulating assisted migration

B.To discuss ways in which plants and animals adapt to climate change

C.To discuss a controversial approach to conserving plant and animal species

D.To describe a recently discovered consequence of global warming

Q2:2.According to the professor,what problem is assisted migration intended to overcome?

A.To diminishing amount of undeveloped land that species can migrate through

B.The relative lack of nutrients available in cooler latitudes and higher elevations

C.The increase in alternations between cool and warm periods

D.Competition from other species in certain native habitats

Q3:3.What point does the professor make when she discusses the cane toad?

A.Translocated species sometimes die out from lack of food.

B.Translocated species may spread too quickly in their new environment.

C.Several techniques are available to achieve assisted migration.

D.Animal species are often easier to translocate than plant species are.

Q4:4.What does the professor imply when she mentions translocating networking of species?

A.There are aspects of species interdependency that are unknown.

B.Some species evolve in ways that help them survive in new habitats.

C.It is difficult to know how far to move a network of species from its native habitat.

D.Many assisted-migration plans should involve the translocation of just one species.

Q5:5.What does the professor imply about the government’s role in regulating assisted migration in the United States?

A.The government should continue to encourage assisted migration.

B.The government has created policies that have proved unhelpful.

C.The government should follow the example set by other countries.

D.The government needs to increase its involvement in the issue.

Q6:6.What is the professor’s attitude toward the effort to save the Florida torreya?

A.She is glad that some conservationists are willing to take a chance on assisted migration.

B.She is concerned because it may have unintended consequences.

C.She is surprised because other species are more endangered than Florida torreya is.

D.She expects the effort will have to be repeated several times before it succeeds.

四、Assisted Migration Conservation托福听力答案：

A1:正确答案：C

A2:正确答案：A

A3:正确答案：B

A4:正确答案：A

A5:正确答案：D

A6:正确答案：B