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Now listen to a part of the lecture on the topic you just read about.
现在来听一段有关你刚刚读到的话题的演讲。
You've just read about three ways to save Torreya taxifolia.
你们刚刚读到了三种拯救佛罗里达榧的方法。
Unfortunately, none of these three options provides a satisfactory solution.
很遗憾，这三个选择里没有一种是令人满意的方法。
About the first solution, reestablishing Torreya in the same location.
关于第一个方法，在相同位置恢复香榧树。
That's unlikely to be successful, because of what's happening to the coolest, dampest areas within Torreya's microclimate.
这不可能会成功，因为香榧树微环境里最冷最潮湿的地方正在发生着什么。
These areas are being strongly affected by changes in the climate of the larger region.
这些地方被大区域里的气候变化大大地影响了。
This could be because global warming has contributed to an increasing overall temperatures in the region or because wetlands throughout Florida have been drained.
这可能是因为全球变暖导致了该地区整体温度的上升，也可能是因为整个佛罗里达地区的湿地都被抽干。
Either way, many areas across the region are becoming drier.
无论是那种原因，该区域的很多地方都变得很更干燥。
So it's unlikely that Torreya would have the conditions it needs to survive anywhere within its original Florida microclimate.
所以在它原始微环境的任何地方，香榧树都不太可能会有它生存所需要的条件。
Now, about the second solution, relocating Torreya far from where it currently grows?
现在，关于第二个解决方案，把香榧迁移到远离它目前生长的地方。
Well, let's look at what happened when humans helped another tree, the black locust tree, move north to a new environment.
恩，让我们看看人类帮助另一种树--刺槐树，把它北移到一个新的环境的时候发生了什么。
When they did this, the black locust tree spread so quickly that it killed off many plants and trees in the new environment,
当他们这样做的时候，刺槐树蔓延得太快，以至于它消灭了新环境里的许多植物和树木，
and some of these plants and trees were themselves already in danger of becoming extinct.
并且这些植物和树木中的一些它们自己已经处于绝种的危险中。
So assisted migration can have unpredicted outcomes for the new environment.
所以，协助迁移对新环境来说会有无法预料的结果。
Third, research centers are probably not a solution either.
第三，试验中心也可能不是一个解决方法。
That's because the population of the Torreya trees, that can be kept in the centers will probably not be able to resist diseases.
因为能被放在研究中心的香榧树数量也许不能抵御疾病。
For a population of trees to survive a disease, it needs to be relatively large and it needs to be genetically diverse.
一种树木想要在疾病中生存，它的数量需要相对大一点，并且需要基因上是多样的。
Tree populations in the wild usually satisfy those criteria.
在野外的树木种群通常能满足这些要求。
But research centers would simply not have enough capacity to keep a large and diverse population of Torreya trees.
但是研究中心没有足够的容量来容纳大量且多样的香榧树。
So trees in such centers will not be capable of surviving diseases in the long term.
所以，长远来说，在那些中心里的树不能在疾病中幸存。
