【TED ED 中英双语】 P40
Attack of the killer algae
藻类杀手的攻击

We've all seen the movies where a monster,
created by a scientist in a laboratory,
escapes to wreak havoc on the outside world.
But what if the monster was not some giant rampaging beast,
destroying a city, but just a tiny amount of seaweed
with the potential to disrupt entire coastal ecosystems?

我们都在电影中看到过
由科学家在实验室创造出来的某个怪兽,
出逃并蹂躏了我们的世界。
但是,如果这个毁灭城市的生物不是 某些巨大狂暴的怪兽,
而仅仅是一小簇
有着破坏整个沿海生态系统的能力的海藻呢?

This is the story of Caulerpa taxifolia,
originally a naturally occurring seaweed
native to tropical waters.
In the 1980s, one strain was found to thrive in colder environments.
This trait, combined with its beautiful, bright green color
and ability to grow quickly without maintenance
made it ideal for aquariums, which it helped keep clean
by consuming nutrients and chemicals in the water.
Further selective breeding made it even heartier,
and soon it was used in aquariums around the world.

这便是杉叶蕨藻的故事,
追溯其源,它来源于热带水域,
是一种自然生长的原生海藻。
在八十年代,发现了一簇生长在寒冷环境中的海藻。
他们还有着美丽的、亮绿色外表,
并且无需养护,迅速生长
是水族箱中的理想的清道夫,
因为它们可以吸收水中的养料和一些化学物质,
精选培育的品种就更贴心了。
很快,便广泛用于世界各地的水族馆中了。

But it was not long before a sample of this
aquarium-developed super algae
turned up in the Mediterranean Sea
near the famed Oceanographic Museum of Monaco.
The marine biologist who found it believed that
the museum had accidentally realeased it into the ocean
along with aquarium waters,
while museum directors claimed
it had be carried into the area by ocean currents.

但不久,
在地中海区域
发现了这种为了适应水族馆 特别培育的超级海藻,
就在著名的摩纳哥海洋博物馆附近。
发现海藻的海洋生物学家相信
这是海洋博物馆在倾倒水族箱中的水时
无意将海藻也一同倒入了海洋之中,
然而博物馆负责人坚称
它们是随着洋流飘落到这里的。

Regardless of how it ended up there,
the non-native Caulerpa multiplied rapidly,
having no natural predators
due to releasing a toxin that keeps fish away.
And like some mythical monster, even a tiny piece that broke off
could grow into a whole new colony.
Through water currents and contact with boat anchors and fishing lines,
it fragmented and spread throughout Mediterranean coastal cities
covering coral reefs.

不究其源,
这种外来杉叶海藻迅速繁殖,
没有自然天敌,
因为它们释放出一种毒素以驱赶鱼群
像某种神秘怪兽,即使掉落的一小片海藻
都能长成一个新的完整海藻群落
通过水流作用,或者携挂在船锚和钓鱼线上,
海藻在整个地中海海岸城市传播生长开来。
覆盖在珊瑚礁上。

So what was the result of this invasion?
Well, it depends on who you ask.
Many scientists warned that the spread of Caulerpa
reduces biodiversity by crowding out native species of seaweed
that are eaten by fish,
with the biologist who first discovered its presence dubbing it
Killer Algae.
Other studies instead claim
that the algae actually had a beneficial effect
by consuming chemical pollutants --
one reason the aquariums strain was developed.

这样的入侵,会导致怎样的结果呢?
这取决于对于谁人而言。
很多科学家警告说,杉叶海藻的蔓延
会侵占本地海草物种的生存地, 导致生物多样性锐减,
而本地海草是鱼类的食物。
因此最先发现海藻存在的 生物学家称呼它们为
海藻杀手
另一些研究却声称
这些海藻实际上是有益的
它们能吸收一些化学污染物--
正是如此,才培育了水族馆专用海藻。

But the disruption of a natural ecosystem
by an introduced foreign species
can have unpredictable and uncontrollable effects
that may not be immediately visible.
So when Culerpa taxifolia was discovered
at Carlsbad's Agua Hedionda Lagoon,
near San Diego in the year 2000,
having most likely come from the dumping
of home aquarium water into a connecting storm drain,
it was decided to stop it before it spread.

但是通过引入外来物种
对自然生态系统的破坏
有着不可预见,亦不可控制的结果,
也许在短期内无法察觉到这些破坏。
所以在2000年,杉叶海藻被发现
出现在圣地亚哥附近的
卡尔斯巴德的黑迪翁达礁湖中,
它们可能是,家庭水族箱在倾倒废水时
通过连接的排水管道传播的,
人们决定采取措施控制其蔓延。

Tarps were placed over the Culerpa colonies
and chlorine injected inside.
Although this method killed
all other marine life trapped under the tarps,
it did succeed in eradicating the algae
and native eelgrass was able to emerge in its place.
By responding quickly, authorities in California
were able to prevent Culerpa from propagating.
But another occurrence of the strain,
in the coastal wetlands of southeast Australia,
was left unchecked and allowed to spread.
And unfortunately, a tarp cannot cover the Mediterranean Sea
or the Australian coast.

防水布被铺放在海藻群上
并注入了氯气
虽然这项举措
杀死了所有防水布之下的海洋生物,
但是,根除海藻行动的确成功了
而且使得本地的鳗草在此地生存。
加州当局反应迅速,
海藻的疯长得以控制。
但是海藻的另一股势力
在澳洲西南部的海岸湿地处
迅速蔓延,无法控制。
而不幸的是,一块防水布 无法覆盖整个地中海,
或者是澳洲海岸。

Invasive species are not a new problem,
and can indeed occur naturally.
But when such species are the results of
human directed selective breeding or genetic modification
and then released into the natural environment,
their effect on ecosystems
can be far more radical and irreversible.

物种入侵并不是一个新难题。
在大自然中时有发生。
但是当这一入侵物种
经过人工挑选培育或者基因优化后
之后被投放回大自然,
他们对生态系统的影响
将是更彻底而又无法挽回的。

With the proliferation of new technologies
and multiple threats to the environment,
it is more important than ever for scientists
to monitor and evaluate the risks and dangers,
and for the rest of us to remember
that what starts in our backyard
can effect ecosystems half a world away.

随着新技术不断衍生,
对自然环境出现了越来越多的威胁,
比以往任何时候更重要的是
科学家应当关注考量所有的风险危害。
对于我们来说应当牢记
那些种植在后院的植物
或许会影响到另外一个半球的生态系统。