The Unexpected, Underwater Plant Fighting Climate Change | Carlos M. Duarte | TED Countdown

翻译人员: Han Lei 校对人员: Yan Li Xiao

I'm here to unveil a new carbon-removal technology,

我来这儿是为了 展示一种全新的，

one out of sight and uncelebrated.

并且不为人知的除碳技术。

Meet our champion: seagrass.

今天的主角就是海草。

A very unlikely champion,

可能出乎意料，

but yet a remarkable power of carbon removal.

但它的确是一股除碳的卓越势力。

Seagrasses occupy only 0.1 percent of the seafloor,

海草仅占据了海底面积的 0.1%，

but they remove one-third of all of the carbon

但它们却移除了每年

that gets sequestered in the seafloor annually.

封存于海底的碳的三分之一。

They are no ordinary seagrasses,

它们不是普通的海草，

and yet, we didn’t know much about them.

然而，我们对他们了解不多。

When I started my journey of research and science with seagrasses

大约四十年前，

当我开始探索和研究 海草的时候，

about four decades ago,

we knew that they were flowering plants

我们那时知道它是显花植物，

that had adapted to grow and colonize the ocean,

已经可以适应并在海洋里肆意生长，

but we didn’t know how amazing the adaptation [were] required

但是我们不知道它是如何适应

to [be to] achieve this feat.

这样的生存环境的。

In fact, only seven years ago,

实际上，我们仅在七年前

we published the first genome sequence of a seagrass,

才提出了海草的 第一个基因序列，

and we were mesmerized at the amazing adaptations that were required

我们被在海洋中大量繁殖

to be able to colonize the ocean.

所需要的惊人适应迷住了。

And now we understand why only 17 species

我们现在明白了

from among 300,000 or so species of flowering plants

为什么在生物圈中存在的

that are present in the biosphere

大约 30 万种显花植物里

have conquered the ocean.

只有 17 种征服了海洋。

Seagrasses grow by extending a rhizome --

海草成长的方式是向更深的地下

that is a subterranean stem

延长地下根茎，

that elongates at rates of about one centimeter

这些根茎每年

to about five meters per year,

会长长 1 厘米至 5 米，

and they branch and extend along the seafloor,

沿着海底分支延伸，

forming large clones.

复制繁殖巨大的克隆体。

We knew that clones can be quite large,

我们已经知道了克隆体的体积 可能会很大，

but we were surprised when, in the Mediterranean,

但是十年前我们在地中海看到

we found, 10 years ago,

a clone that occupied 15 kilometers;

一个占据 15 公里的克隆体 依旧十分惊讶，

that is the size of the island of Manhattan.

这相当于曼哈顿岛的面积。

And this is a very remarkable clone,

这是一个惊人的克隆体，

but we also calculated that the seed that gave rise to this clone

但我们也分析了 产生这个克隆体的种子

germinated in the seafloor 200,000 years ago.

是二十万年前在海底萌发的。

This is one of the oldest living things on the planet,

这是这个星球上最古老的生命之一，

and the meadow where this megaclone is growing

这个巨型克隆体成长的温床

is now recognized as a marine World Heritage site.

现在被认定为世界海洋遗产。

Off the island of Ibiza,

这块区域位于 伊维萨岛（Ibiza）外，

this meadow occupies about 800 square kilometers

占地 800 平方公里

and is now recognized as a protected area,

现在被列为保护区，

not just because of the long life span of the clones

不仅仅是因为克隆体的长寿，

but also because of the biodiversity it supports.

还因为它维持着当地的生物多样性。

But we also found that this meadow

但是我们也发现这块区域

is also the champion of carbon sequestration in the biosphere,

也是生物圈碳封存的

with one hectare of this seagrass sequestering as much carbon

一公顷的海草可以 和 15 公顷的原始亚马逊森林

as 15 hectares of pristine Amazonian forest.

吸收同样多的碳。

Finding [out] how this is possible was a path of discovery.

我们来探寻怎么会造就这样的情形。

First, the canopies of these plants are very large,

首先，这些植物的树冠非常大，

and they are among the most productive ecosystems on Earth,

它们是地球上最具生产力的生产者，

pumping carbon dioxide into organic matter at amazing rates,

将二氧化碳 以惊人的速度转化为有机物，

that produce a lot of carbon,

它们生产了很多的碳，

much of that being sequestered in the soils

其中的大部分被封存在土壤里

as rhizomes and roots that are very hard to decompose.

根茎和根是很难分解的。

The large canopies also form a web

巨大的树冠也形成了一张网

that dissipates energy and filters out particles from the flow

这就耗散了能量， 过滤掉了气流中的微粒，

that settle, then, in the seafloor, protected from being resuspended

那沉在海底的东西， 通过被树冠的保护层覆盖

by the protective cover of the canopy.

就不会再浮上来了。

And these particles in the seafloor decompose very slowly,

这些微粒在海底被分解的很慢，

because the seafloor and the soils of seagrasses

因为海床和土壤里的海草

are devoid of oxygen,

都缺乏氧气，

and that slows down microbial decomposition.

这就减缓了微生物的分解。

So this carbon accumulates and is preserved in the soils.

所以这些碳积累并保存在土壤中。

And there's one more reason

这里还有一个原因

why these seagrass meadows are so effective at sequestering carbon.

可以解释为什么这些海草 草地能如此有效地吸收碳。

And it’s that, unlike forests,

与森林不同的是，

where carbon in the soil gets emitted back to the atmosphere

通过森林大火，

with wild forest fires --

土壤中的碳在哪里被排放回大气—

which, unfortunately, are becoming more frequent with climate change --

不幸的是，随着气候变化， 这种情况正变得越来越频繁，

there are no fires underwater,

在水中不会有火焰，

so the carbon that settles in the soils of seagrass is safe

所以沉淀在海草土壤中的碳是安全的，

and accumulates over thousands of years, safely.

经过数千年的积累变得非常安全。

In fact, seagrasses not only grow along the seafloor --

事实上，海草不仅生长在海床上，

they also raise the seafloor upwards

它们也会 以每年 1 到 4 毫米的速度

at rates of one to four millimeters per year,

使海底向上隆起，

and they do so, over centennial timescales,

在 100 年的时间里，

to the point that these seagrasses form reefs,

这些海草形成了珊瑚礁，

such as this four-meter-tall reef of seagrass peat

比如这个四米高的海草泥炭礁

that is found in the Mediterranean.

它是在地中海被发现的。

And this is not the tallest seagrass reef that has been discovered.

这并不是目前发现的最高的海草礁。

My colleagues have dug out a seagrass reef

我的同事挖出了一个海草礁。

that is 12 meters tall, three times this size.

这个海草礁 13 英尺高， 是这个海草礁的三倍。

Just imagine the amazing amount of carbon

想象一下被封存在这些海草礁中的

that is being held in these seagrass reefs.

碳的数量有多惊人。

But it is not only carbon.

但是不仅有碳。

The seagrass reef protects the shorelines,

海草礁保护着海岸线，

protects our infrastructure,

保护着我们的基础设施，

protects our property and protects our lives.

保护着我们的财产 还保护着我们的生命。

And this protection becomes particularly important

在现在，这些保护在气候 变暖海平面上升

at a time when climate change is raising sea levels

变得尤为重要，

and is also leading to increasingly strong storms and cyclones.

也导致了越来越强的风暴和气旋。

So very often,

所以很多时候，

seagrasses form the first line of defense for the shorelines.

海草形成了海岸线的第一道防线。

So as we became aware of the important role of seagrass

所以当我们意识到海草土壤固碳

in carbon sequestration,

的重要作用时，

and also in defending our shorelines,

同时也在保卫在我们的海岸线上，

then we were almost too late to benefit from those protections,

那时我们几乎来不及 从这些保护措施中受益，

because, sadly, we had lost a lot of seagrass in the ocean.

因为我们在海洋中有着大量的海草。

In the 1930s,

在二十世纪三十年代，

disease wiped out seagrass along both sides of the Atlantic.

这种疾病消灭了大西洋两岸的海草。

And as they were starting to recover,

他们现在开始恢复这些海草，

sewage input and agricultural runoff

污水输入和农业径流

led to mortality of seagrass along the shores of all continents,

导致了各大洲沿岸海草的死亡，

and that was aggravated further with mechanical damage,

机械损伤使情况进一步恶化，

such as the dragging of this anchor from a megayacht in the Mediterranean

比如从地中海的 一艘巨型游艇上拖出这个锚

that is plowing away this millenary seagrass,

在耕耘这千年海草，

exposing the sediment and resuspending it

暴露沉淀物，重新悬吊，

so that it will be emitted back into the atmosphere as carbon dioxide.

这样它就会以二氧化碳 的形式被排放到大气中。

And that was compounded with dredging, trawling and coastal works

此外还有疏浚、拖网和沿海工程

that impacted seagrass.

同样也影响了海草。

So by the end of the 20th century,

到了 20 世纪末，

we calculated that one-third of the known seagrass areas in the ocean

我们计算了海洋中 三分之一的已知海草区域

had been lost.

已经消失了。

And yet efforts to protect them became urgent.

然而，保护它们的 努力变得迫在眉睫。

But we can only protect what we know,

但是我们只能保护 我们现在知道的种类，

and our knowledge of the distribution and area of seagrasses in the ocean

以及我们对海洋中 海草分布和面积的了解

is still very poor.

仍然非常匮乏。

Our estimates range between 150,000 square kilometers

我们估算了 在 15 万平方公里

to one million square kilometers.

到 1 百万平方公里之间。

And narrowing down this uncertainty is very, very challenging.

缩小这种不确定性 是非常非常具有挑战性的。

In fact, it can only be done by scuba divers,

事实上， 只有戴水肺的潜水员才能做到，

because seagrass meadows cannot be resolved from satellites

因为海草草地无法从卫星上分辨出来

or from airborne sensors,

或者从机载传感器，

because the deeper parts cannot be differentiated

因为更深的部分 从其他类型的地面和海底

from other types of grounds and seafloors.

无法区分。

So we are actually partnering with much better swimmers than we are,

所以实际上我们在 和比我们更好的游泳健将合作，

but that share our interest in seagrass meadows.

但它们和我们一样对海草甸感兴趣。

We are partnering with green sea turtles,

我们和绿海龟合作，

which are mostly feeding on seagrasses,

它们主要以海草为食，

so we track them with satellite devices

所以我们用卫星设备追踪他们

to find out where their feeding grounds are,

为了找到它们的觅食地，

and by doing this, we are finding and discovering

通过这样做，我们正在寻找和发现

new seagrass meadows in the Indian Ocean and the Red Sea,

印度洋和红海的新海草草地，

which were poorly studied.

这方面的研究很少。

And in the Bahamas,

在巴哈马群岛，

we are now partnering with tiger sharks,

我们现在和虎鲨合作，

because we found that in the Bahamas,

因为我们在巴哈马发现，

tiger sharks spend about 70 percent of their time

虎鲨大约 70% 的时间

cruising over seagrass meadows.

都在海草草地上巡航。

And we instrumented, last year, for the first time,

去年，我们第一次用仪器，

a tiger shark with 360-degree cameras,

在虎鲨身上装了 360 度的摄像机，

which are sitting on the fin of the shark

它们固定在鲨鱼的鳍上

so that when the cameras pop up to the surface,

所以当摄像机出现在水面上时，

then we retrieve the footage,

然后我们再取回录像，

and we can ascertain in which areas of the track there were seagrasses.

我们可以确定哪些地方长了海草。

So using tiger sharks as partners,

所以和虎鲨成为了合作伙伴，

we have now discovered that the Bahamas' banks --

我们现在发现巴哈马群岛的河床—

which a US astronaut, Scott Kelly,

美国宇航员斯科特·凯利，

deemed to be the most beautiful sight from space

当他分享这张他从太空拍的照片时，

when he shared this photo that he took from space --

他认为这是太空中最美的风景—

is actually the largest seagrass meadow in the ocean.

实际上是海洋中最大的海草草地。

And we are now growing policies to protect seagrasses

我们现在正在制定保护海草

and improve water quality

和改善水质的政策，

so that we can recover seagrasses.

这样我们就能恢复海草。

And I tell you what, these policies are working.

我如实说，这些政策正在起作用。

And over the last two decades,

在过去的二十年里，

we have seen a rebound of seagrasses

在经历了近一个 世纪的持续衰退之后，

following almost a century of sustained decline.

我们已经看到海草数量的回升。

Now seagrasses are starting to expand and recover

现在海草开始扩张和恢复

along the shores of Europe, North America, Japan, Australia and China.

沿着欧洲和北美海岸 日本，澳大利亚和中国。

And this is only the beginning,

而这仅仅是个开始，

because we can do more than just protect seagrasses

因为我们能做的不仅仅是保护海草

and wait for them to come back.

并等它恢复过来。

We can engage in active restoration,

我们可以进行积极的修复，

such as my colleagues in Virginia have done.

就像我在弗吉尼亚州 的同事所做的那样。

And in the early years of this century,

在本世纪初，

they released 7.5 million seeds of seagrasses in South Bay,

他们在南湾，在弗吉尼亚的沿海水域

in the coastal waters of Virginia.

释放了 750 万颗海草种子。

And 16 years later,

16 年后，

the seagrass has expanded to 20 square kilometers,

海草将扩展到 20 平方公里，

and by now it has covered, already 36 square kilometers.

到目前为止， 它已经覆盖了 36 平方公里。

The amount of carbon that this restored seagrass meadow has trapped

恢复的海草草地捕获的大量的碳

is so important that it has led the Commonwealth of Virginia,

是如此重要， 以至于它领导了

that owns these waters,

拥有这片水域的弗吉尼亚州，

to pass a bill that regulates how carbon grades

通过一项规范碳等级

from seagrass restoration

让海草恢复的法案

should be reinvested back in further restoration of seagrass,

应该重新投资于海草的进一步恢复，

and also in improving our understanding of seagrass ecology.

同时也增进了 我们对海草生态学的理解。

But seagrasses are more than just carbon.

但是海草不仅仅是碳。

They also have seeds,

它们也有种子，

and my friend and three-star Michelin chef, Ángel León,

还有我的朋友，三星 米其林大厨，Ángel León，

has released this year an important development,

公布了今年的一项重要进展，

which is that these seeds can be consumed by humans

那就是这些种子

as marine rice.

可以被人类作为海洋大米食用。

And this is a wonderful crop,

这是一种很棒的作物，

one that does not require arable land, fresh water,

一个不需要耕地，淡水，

neither fertilizers nor herbicides or pesticides.

不用化肥，不用除草剂， 也不用杀虫剂。

And because we only need to clip the flower and shoots where the seeds are,

因为我们只需要 剪下种子所在的花和嫩枝，

we don't need to harvest the plant,

我们不需要收割植物，

so the meadow continues to sequester carbon,

所以草地继续吸收碳，

promote biodiversity and defend our shorelines.

促进生物多样性， 保护我们的海岸线。

And these findings, in the past decade,

通过这些发现，在过去的十年里，

have made me believe that it's time to ditch the idea

让我相信是时候放弃

that seagrasses are the ugly ducklings of environmental conservation,

海草是环境保护的丑小鸭这个想法了，

as I nicknamed them 15 years ago,

这是我 15 年前给它们取的绰号，

frustrated, because at that point,

沮丧，因为那时，

not even conservation NGOs cared.

甚至连环保非政府组织都不在乎。

Now we know that seagrasses are beautiful swans --

现在我们知道海草是美丽的天鹅—

which actually eat seagrass leaves and rhizomes --

它们吃海草的叶子和根茎—

and healthy seagrass meadows are harbingers of a healthy ocean.

健康的海草草地是健康海洋的先兆。

And I am inspired by the tide change

我受到了

from a century of loss of seagrass

从一个世纪以来海草的损失，

to two decades of recovery

到用二十年来恢复，

to imagine that we can actually do better.

到想象我们能做得更好 之间潮汐变化的启发。

We can expand this success story to the rest of marine life,

我们可以把这个成功的故事 扩展到其他的海洋生物，

and last year, we published a paper in the journal "Nature,"

去年，我们在《自然》 杂志上发表了一篇论文，

where we pledged that it's possible to recover

我们保证过有可能恢复的地方

and rebuild the abundance of life in the ocean by 2050.

并在 2050 年前 重建丰富的海洋生物。

Just imagine that it is within our [grasp]

想象一下把一个健康的海洋

to hand over a healthy ocean to our children and grandchildren.

留给我们的子孙后代 就在我们的掌控之中。

And as we do so,

当我们这样做的时候，

we can also step up in our race to stabilize our climate.

我们也可以加快稳定气候的步伐。

Thank you.

谢谢。

(Cheers and applause)

（欢呼声和掌声）