at a conference dedicated to things not seen,

這似乎有些好笑

and present my proposal to build

在會議上談論肉眼看不到的東西

a 6,000-kilometer-long wall

並提出我的建議

across the entire African continent.

建立一條6000公里長的牆

About the size of the Great Wall of China,

橫跨全非洲大陸

this would hardly be an invisible structure.

大約像中國長城的規模

And yet it's made from parts that are invisible, or near-invisible, to the naked eye:

這會是個你很難不看到的結構

bacteria and grains of sand.

雖然它的組成來自於幾乎看不見，或接近肉眼看不見的程度

Now, as architects we're trained to solve problems.

也就是細菌和沙粒

But I don't really believe in architectural problems;

身為建築師我們 被訓練來解決問題

I only believe in opportunities.

但我並不相信建築上的問題

Which is why I'll show you a threat,

我只相信機會

and an architectural response.

這就是為什麼我將向你們說明這個威脅

The threat is desertification.

以及一個建築上的因應措施

My response is a sandstone wall

所謂的威脅是沙漠化

made from bacteria and solidified sand,

我的因應措施是建一座砂岩牆

stretching across the desert.

由細菌和固化沙組成

Now, sand is a magical material

延伸橫跨沙漠

of beautiful contradictions.

沙是一種神奇的物質

It is simple and complex.

美麗又矛盾

It is peaceful and violent.

簡單又複雜

It is always the same, never the same,

和平又狂暴

endlessly fascinating.

它看來永遠一個樣，卻又那麼不同

One billion grains of sand

無窮的迷人特質

come into existence in the world each second.

這世界每秒鐘

That's a cyclical process.

有10億粒沙形成

As rocks and mountains die,

這是一個循環過程

grains of sand are born.

當岩石和山脈消逝

Some of those grains may then cement naturally into sandstone.

沙粒則形成

And as the sandstone weathers, new grains break free.

有些沙粒之後可能自然地凝固為砂岩

Some of those grains may then accumulate

當砂岩受到風化，新的沙就會脫離

on a massive scale,

有些沙粒

into a sand dune.

則大規模累積

In a way, the static, stone mountain

形成沙丘

becomes a moving mountain of sand.

在某種情況下，靜止的岩山

But, moving mountains can be dangerous. Let me try and explain why.

會變成一座移動的沙山

Dry areas cover more than one third of the Earth's land surfaces.

但移動的山很危險，讓我試著解釋原因

Some are already deserts;

超過1/3的地球表面覆蓋著乾燥的區域

others are being seriously degraded by the sand.

有一些已成為沙漠

Just south of the Sahara we find the Sahel.

其他的則是正嚴重地受到沙的侵蝕

The name means "edge of the desert."

我們發現撒哈拉沙漠南方的薩赫耳

And this is the region most closely associated with desertification.

薩赫耳意謂「沙漠的邊緣」。

It was here in the late '60s and early '70s

這區域是最近乎於沙漠化的地方

that major droughts brought three million people

在60年代末期及70年代初期，嚴重的乾旱

to become dependent upon emergency food aid,

造成三百萬人急需

with about up to 250,000 dying.

仰賴緊急食物救援

This is a catastrophe waiting to happen again.

而將近有25萬人死亡

And it's one that gets very little attention.

這是一場即將再次發生的災難

In our accelerated media culture,

而這個災難卻沒獲得多少注意

desertification is simply too slow

在我們的快速媒體文化當中

to reach the headlines.

由於沙漠化的緩慢

It's nothing like a tsunami or a Katrina:

使它從未登上頭版，不受媒體重視

too few crying children and smashed up houses.

它不像海嘯或是卡崔那颶風

And yet desertification

看不到什麼哭泣的兒童及毀壞的房屋

is a major threat on all continents,

然而，沙漠化

affecting some 110 countries

在所有陸地上都是重大威脅

and about 70 percent of the world's agricultural drylands.

它影響110個國家

It seriously threatens the livelihoods

以及世界上約 70%的農作陸地

of millions of people,

它嚴重威脅

and especially in Africa and China.

數千萬人的生活

And it is largely an issue that we've created for ourselves

特別是非洲及中國

through unsustainable use of scarce resources.

這主要也是由於我們

So, we get climate change.

濫用珍貴資源所導致的問題

We get droughts,

所以我們面臨著氣候異常

increased desertification,

乾旱

crashing food systems, water scarcity,

沙漠化擴大

famine, forced migration,

崩潰的食物系統、水荒

political instability, warfare, crisis.

飢荒、被迫遷徙

That's a potential scenario

政治不穩定、戰爭、危機

if we fail to take this seriously.

這些將是潛在的情況

But, how far away is it?

如果我們不認真看待這個問題的話

I went to Sokoto in northern Nigeria

但是，這個威脅離我們有多遠呢？

to try and find out how far away it is.

我去了奈吉利亞北部的索科托（Sokoto）

The dunes here move southward at a pace of around 600 meters a year.

試圖瞭解它離我們有多遠

That's the Sahara eating up almost [two meters] a day of the arable land,

這裏的沙丘南移速度約是一年600公尺

physically pushing people away from their homes.

這等於是撒哈拉每天侵吞下一公尺的耕作用地

Here I am -- I'm the second person on the left --

完全將人們趕離他們的家園

(Laughter)

我在這裡—我是左邊數過來第二個

with the elders in Gidan-Kara,

（笑聲）

a tiny village outside of Sokoto.

與一些長者

They had to move this village in 1987

在索科托近郊的小村落Gidan-Kara

as a huge dune threatened to swallow it.

他們必須於1997年遷移這個村莊

So, they moved the entire village, hut by hut.

因當時遭受一個巨大沙丘吞沒的威脅

This is where the village used to be.

於是將整個村莊的一間間小屋陸續遷移

It took us about 10 minutes to climb up to the top of that dune,

這是村莊之前所在處

which goes to show why they had to move to a safer location.

我們花了約 10 分鐘爬上沙丘頂端

That's the kind of forced migration

可以看出他們為什麼必須遷移到安全地點

that desertification can lead to.

這是一種強迫性的遷徙

If you happen to live close to the desert border,

沙漠化會導致這種後果

you can pretty much calculate how long it will be

如果你碰巧住在靠近沙漠邊緣

before you have to carry your kids away,

你幾乎可以計算出在這之前還剩多少時間

and abandon your home and your life as you know it.

你得帶著你的孩子離開

Now, sand dunes cover only about one fifth of our deserts.

放棄你的家庭和生活，當你知道會發生這種狀況時

And still, those extreme environments are very good places

目前沙丘只覆蓋我們的沙漠約1/5

if we want to stop the shifting sands.

儘管如此，這些極端環境依然是很好的地方

Four years ago, 23 African countries

如果我們阻止沙的移動

came together to create the Great Green Wall Sahara.

四年前，23個非洲國家

A fantastic project, the initial plan

聚首提議建立「撒哈拉綠色長城」

called for a shelter belt of trees to be planted

這是一個了不起的計畫，初步的規劃

right across the African continent,

是種植防護林帶

from Mauritania in the west, all the way to Djibouti in the east.

橫越整個非洲大陸

If you want to stop a sand dune from moving,

從西部的茅利塔尼亞一直到東部的吉布地

what you need to make sure to do is to stop the grains

如果想阻止沙丘移動

from avalanching over its crest.

你必須確保能阻止沙粒

And a good way of doing that, the most efficient way,

從沙丘頂端崩塌

is to use some kind of sand catcher.

有個好方法，也是最有效的方法

Trees or cacti are good for this.

是使用某種能捕捉沙粒的東西

But, one of the problems with planting trees is that

樹木或仙人掌很有用

the people in these regions are so poor

但是，種樹木的問題之一是

that they chop them down for firewood.

這裡的居民很貧窮

Now there is an alternative to just planting trees

他們把樹木砍來當柴燒

and hoping that they won't get chopped down.

現在有個替代方案 能取代只是種植樹木

This sandstone wall that I'm proposing essentially does three things.

並希望它們不會被砍伐

It adds roughness to the dune's surface,

我建議的這個砂岩牆主要可達成三項任務

to the texture of the dune's surface, binding the grains.

添加粗糙物到沙丘表面

It provides a physical support structure for the trees,

為沙丘表面紋理增添粗糙面，黏住沙粒

and it creates physical spaces,

它為樹木提供自然的支撐結構

habitable spaces inside of the sand dunes.

並建立了實際空間

If people live inside of the green barrier

就是沙丘中的可居住空間

they can help support the trees, protect them from humans,

如果人們生活在綠色壁壘中

and from some of the forces of nature.

他們可以協助支撐樹木，保護樹木

Inside of the dunes we find shade.

不受人類及其他自然破壞力的侵害

We can start harvesting condensation,

沙丘中我們有蔭涼處

and start greening the desert from within.

我們可以取得冷凝水

Sand dunes are almost like ready-made buildings in a way.

而開始從內部綠化沙漠

All we need to do is solidify the parts that we need to be solid,

沙丘有點像是現成的建築物

and then excavate the sand,

我們所要做的是固化我們所需的部份

and we have our architecture.

然後將沙挖掘出來

We can either excavate it by hand

這就是我們的建築物

or we can have the wind excavate it for us.

我們可以徒手挖掘

So, the wind carries the sand onto the site

讓風來幫我們代勞

and then it carries the redundant sand away from the structure for us.

所以風將沙吹到當地

But, by now, you're probably asking,

又幫我們將多餘的沙從結構中吹走

how am I planning to solidify a sand dune?

現在你們可能要問我

How do we glue those grains of sand together?

如何固化沙丘？

And the answer is, perhaps, that you use these guys,

我們要如何將沙粒黏合在一起

Bacillus pasteurii,

或許答案就是，你該用這東西

a micro-organism that is readily available in wetlands

巴氏芽孢桿菌

and marshes, and does precisely that.

一種在濕地和沼澤中

It takes a pile of loose sand

都可以找到的微生物

and it creates sandstone out of it.

它需要一堆鬆散的沙子

These images from the American Society for Microbiology show us the process.

並由此創造出砂岩

What happens is, you pour Bacillus pasteurii onto a pile of sand,

這些美國微生物學會的影像，展示出固化的過程

and it starts filling up the voids in between the grains.

所發生的就是，你將巴氏芽孢桿菌倒入一堆沙中

A chemical process produces calcite,

這些菌開始填滿沙粒間的空隙

which is a kind of natural cement

經過化學過程，產生方解石

that binds the grains together.

這是一種天然的水泥

The whole cementation process takes about 24 hours.

可使沙粒結合在一起

I learned about this from a professor at U.C. Davis called Jason DeJong.

整個膠結過程約需24小時

He managed to do it in a mere 1,400 minutes.

我跟加州大學戴維斯分校Jason DeJong副教授學到這個方法

Here I am, playing the part of the mad scientist,

他僅在1400分鐘內就能成功做到這一點

working with the bugs at UCL in London,

這是我，就像一位瘋狂的科學家

trying to solidify them.

在倫敦 UCL 裏操作這些桿菌

So, how much would this cost?

試圖使它們固化

I'm not an economist, very much not,

這需要多少費用？

but I did, quite literally, a back of the envelope calculation --

我不是經濟學家，差遠了

(Laughter)

但我毫不誇張地 粗步估算一下

-- and it seems that for a cubic meter of concrete

（笑聲）

we would have to pay in the region of 90 dollars.

1立方公尺的水泥

And, after an initial cost of 60 bucks to buy the bacteria,

我們大約要支付90美元

which you'll never have to pay again,

第一次購買這些細菌的60美元後

one cubic meter of bacterial sand

你就不需要再買細菌

would be about 11 dollars.

1立方公尺的細菌沙

How do we construct something like this?

約11美元

Well, I'll quickly show you two options.

究竟我們要如何建造這樣的建築？

The first is to create a kind of balloon structure,

我很快的提供你兩個選項

fill it with bacteria, then allow the sand to wash over the balloon,

第一個是建造一種似氣球的結構

pop the balloon, as it were, disseminating the bacteria into the sand and solidifying it.

用細菌填滿它，然後讓沙浸過氣球

Then, a few years afterwards,

打破氣球，可以這麼說，將細菌散入沙中使它固化

using permacultural strategies,

然後，數年後

we green that part of the desert.

使用永續策略

The second alternative would be to use injection piles.

我們綠化了那部分的沙漠

So, we pushed the piles down through the dune,

第二種選項是使用灌樁

and we create an initial bacterial surface.

我們將樁打入沙丘

We then pull the piles up through the dune

創造出一個初始化的細菌表面

and we're able to create almost any conceivable shape inside of the sand

然後將樁抽離沙丘

with the sand acting as a mold as we go up.

如此我們能夠在沙丘內創造出任何想要的形狀

So, we have a way of turning sand into sandstone,

在搭建起來時把沙當成模

and then creating these habitable spaces inside of the desert dunes.

我們就有將沙轉換為沙岩的方式

But, what should they look like?

而且在沙丘裡創造出可居住的空間

Well, I was inspired, for my architectural form, by tafoni,

但是，這些建築會長成什麼樣子呢？

which look a little bit like this, this is a model representation of it.

對於建築外型的靈感源於風化穴

These are cavernous rock structures that I found on the site in Sokoto.

長得有點像這個，這是模型的示意

And I realized that if I scaled them up, they would provide me

這些是有我在Sokoto找到的洞穴狀岩石結構

with good spatial qualities,

然後我發覺，若我將規模拉大

for ventilation, for thermal comfort, and for other things.

它們可以提供我

Now, part of the formal control over this structure

通風、保溫及其他方面良好且特別的品質

would be lost to nature, obviously,

這架構的形式控制一部份

as the bacteria do their work.

將隨大自然消逝，想當然爾地

And I think this creates a kind of boundless beauty actually.

因為細菌有所作用

I think there is really something in that articulation

我覺得 這實際上創造出一種無限的美感

that is quite nice.

認為由這個所表現出的

We see the result, the traces, if you like,

確實有某些相當不錯的理念

of the Bacillus pasteurii being harnessed to sculpt the desert

我們看到其結果和進程，若你願意，

into these habitable environments.

就是利用巴氏芽孢桿菌

Some people believe that

將沙漠雕塑成這些居住環境

this would spread uncontrollably,

有些人相信

and that the bacteria would kill everything in its way.

這方式會一發不可收拾

That's not true at all.

細菌會在運作的過程中侵蝕每一件事物

It's a natural process. It goes on in nature today,

這完全不正確

and the bacteria die as soon as we stop feeding them.

這是個自然的過程，到今日都在自然界發生

So, there it is --

只要我們停止餵食細菌，細菌就會死亡

architectural anti-desertification structures

這就是

made from the desert itself.

由沙漠所製成的

Sand-stopping devices, made from sand.

反沙漠化建築結構

The world is likely to lose one third of its arable land

擋沙裝置是由沙所製成

by the end of the century.

在本世紀末　地球很可能

In a period of unprecedented population growth

減少三分之一的耕地

and increased food demands, this could prove disastrous.

在這史無前例的人口爆炸年代

And quite frankly, we're putting our heads in the sand.

食物需求激增 這些都代表著災難

If nothing else, I would like for this scheme to initiate a discussion.

老實說我們仍是鴕鳥心態

But, if I had something like a TED wish,

若沒有其他資源，我希望這個計畫可以引發討論

it would be to actually get it built,

但是若我有像TED的願景

to start building this habitable wall,

那將是能夠真正將它實現

this very, very long, but very narrow city in the desert,

開始建造這種可居住的牆

built into the dunescape itself.

這將是沙漠中非常長　且狹窄的城市

It's not only something that supports trees,

內建在沙丘結構本身

but something that connects people and countries together.

它不只可以支撐樹木

I would like to conclude by showing you an animation of the structure,

也可以將人們及國家串連在一起

and leave you with a sentence by Jorge Luis Borges.

我想以一段結構的動畫影片作為總結

Borges said that "nothing is built on stone,

並附上波赫士所說的一句話

everything is built on sand,

波赫士說：「沒有建物是建築在岩石上的

but we must build as if the sand were stone."

所有的建物都是建在沙上

Now, there are many details left to explore in this scheme --

但我們必須視沙猶如岩石般來建立一切

political, practical, ethical, financial.

現在這個計畫仍有許多細節有待探索

My design, as it takes you down the rabbit hole,

如政治、實際操作、道德、財務等面向

is fraught with many challenges

如同帶你仙境一遊般

and difficulties in the real world.

我的設計在現實生活中

But, it's a beginning, it's a vision.

是充滿許多挑戰及困難

As Borges would have it, it's the sand.

不過這是個開端，是個願景

And I think now is really the time

如同波赫士所言　它是沙

to turn it into stone. Thank you.

我認為現在

(Applause)

是將它們變成石頭的時候了　謝謝