I'm guessing you're thinking of a collection of trees,

我猜你們一定在想一叢叢樹，

what we foresters call a stand,

我們林務員把那叫作林分，

with their rugged stems and their beautiful crowns.

帶有堅挺的樹幹和美麗的樹冠。

Yes, trees are the foundation of forests,

是的，樹木是森林的基礎，

but a forest is much more than what you see,

但是一片森林遠不止你見到的那樣，

and today I want to change the way you think about forests.

今天我想要改變你們對森林的看法。

You see, underground there is this other world,

你們看，在地下有這樣一個另外的世界，

a world of infinite biological pathways

一個有著無限生物路徑

that connect trees and allow them to communicate

聯繫著樹木，允許它們交流，

and allow the forest to behave as though it's a single organism.

允許這片森林像一個有機體一樣運作的世界。

It might remind you of a sort of intelligence.

它可能讓你想到一種智能。

How do I know this?

我是怎麼知道這種智能的呢？

Here's my story.

這就是我的經歷。

I grew up in the forests of British Columbia.

我在不列顛哥倫比亞省的森林中長大。

I used to lay on the forest floor and stare up at the tree crowns.

我過去常常躺在森林覆被上，向上注視著樹冠。

They were giants.

它們像是巨人。

My grandfather was a giant, too.

我的祖父也是個巨人。

He was a horse logger,

他是一位以馬作為運輸工具的伐木工人，

and he used to selectively cut cedar poles from the inland rainforest.

他過去常常在內陸的熱帶雨林裡有選擇性地砍伐雪松樹。

Grandpa taught me about the quiet and cohesive ways of the woods,

祖父教會了我森林安靜而又協調一致的生活方式，

and how my family was knit into it.

以及我的家庭是如何融合在其中的。

So I followed in grandpa's footsteps.

所以我繼承了我祖父的事業。

He and I had this curiosity about forests,

我和他對森林有著好奇心，

and my first big "aha" moment

而且我第一個恍然大悟的時刻

was at the outhouse by our lake.

是在我們湖邊的外圍建築那裡。

Our poor dog Jigs had slipped and fallen into the pit.

我們可憐的小狗Jigs滑倒然後掉進了一個深坑裡。

So grandpa ran up with his shovel to rescue the poor dog.

所以我的祖父帶著他的鐵鏟跑去救那隻可憐的小狗。

He was down there, swimming in the muck.

他在下面那裡，浸泡在污物中。

But as grandpa dug through that forest floor,

但是當我的祖父翻鬆森林覆被的時候，

I became fascinated with the roots,

我被那些樹根吸引了，

and under that, what I learned later was the white mycelium

在森林覆被下面，我後來得知，是白色菌絲，

and under that the red and yellow mineral horizons.

在菌絲下面，是紅色和黃色的礦質層。

Eventually, grandpa and I rescued the poor dog,

最終，我和我的祖父救了那隻可憐的小狗，

but it was at that moment that I realized

但是正是在那一刻，我意識到

that that palette of roots and soil

樹根和土壤的融合

was really the foundation of the forest.

才真正是森林的基礎。

And I wanted to know more.

而且我想更深入地了解。

So I studied forestry.

所以我攻讀了林學。

But soon I found myself working alongside the powerful people

但是很快我發現自己和有權人士一起工作

in charge of the commercial harvest.

掌管商業收割

The extent of the clear-cutting

清場式伐木的程度

was alarming,

令人擔憂，

and I soon found myself conflicted by my part in it.

而且我很快發現我因為自己在其中扮演的角色而內心鬥爭。

Not only that, the spraying and hacking of the aspens and birches

不僅如此，噴灑藥物以及砍伐山楊樹和樺樹

to make way for the more commercially valuable planted pines and firs

以便栽種具有更高商業價值的松樹和冷杉

was astounding.

令人吃驚。

It seemed that nothing could stop this relentless industrial machine.

似乎沒什麼可以阻止這個無休止的工業機器。

So I went back to school,

所以我回到了學校，

and I studied my other world.

我開始研究我的另一個世界。

You see, scientists had just discovered in the laboratory in vitro

要知道，科學家剛剛在實驗室裡在生物體外發現了

that one pine seedling root

一條松樹苗根

could transmit carbon to another pine seedling root.

可以把碳傳送到另一條松樹苗根那裡。

But this was in the laboratory,

但這是在實驗室裡，

and I wondered, could this happen in real forests?

我想知道，這能在真實的森林裡發生嗎？

I thought yes.

我想是可以的。

Trees in real forests might also share information below ground.

在真實的森林裡的樹木也許也可以在地下分享信息。

But this was really controversial,

但是這真的很有爭議，

and some people thought I was crazy,

一些人認為我發瘋了，

and I had a really hard time getting research funding.

我的確很難得到研究經費。

But I persevered,

但是我堅持不懈，

and I eventually conducted some experiments deep in the forest,

最後我在森林深處進行了一些實驗，

25 years ago.

在25年前。

I grew 80 replicates of three species:

我種植了80棵三類樹種的複本：

paper birch, Douglas fir, and western red cedar.

紙皮樺，黃杉和美西紅側柏。

I figured the birch and the fir would be connected in a belowground web,

我發現樺樹和杉樹會在地下網中聯繫在一起，

but not the cedar.

但是柏樹不行。

It was in its own other world.

它在自己的另外的世界裡。

And I gathered my apparatus,

然後我準備好我的設備，

and I had no money, so I had to do it on the cheap.

因為我沒有錢，所以我必須以低成本的方式完成實驗。

So I went to Canadian Tire --

所以我去了加拿大輪胎公司 －

(Laughter)

（笑聲）

and I bought some plastic bags and duct tape and shade cloth,

我買了一些塑膠袋，膠帶，遮光布，

a timer, a paper suit, a respirator.

一個計時器，一套紙質服裝，和一個防護面罩。

And then I borrowed some high-tech stuff from my university:

然後我從我的大學借了一些高科技設備：

a Geiger counter, a scintillation counter, a mass spectrometer, microscopes.

一個蓋勒計數器，一個閃爍探測器，一個質譜儀器，和顯微鏡。

And then I got some really dangerous stuff:

然後我拿到了一些很危險的東西：

syringes full of radioactive carbon-14 carbon dioxide gas

充滿放射性碳14二氧化碳氣體的注射器

and some high pressure bottles

和一些高壓瓶子

of the stable isotope carbon-13 carbon dioxide gas.

裝有穩定的同位素碳13二氧化碳氣體。

But I was legally permitted.

但是我是合法的。

(Laughter)

（笑聲）

Oh, and I forgot some stuff,

哦，我忘了一些東西，

important stuff: the bug spray,

很重要的東西：殺蟲劑，

the bear spray, the filters for my respirator.

防熊噴霧，和我的防護面罩的過濾器。

Oh well.

好吧。

The first day of the experiment, we got out to our plot

實驗的第一天，我們去了屬於我們的一小塊地，

and a grizzly bear and her cub chased us off.

一隻棕熊和她的小熊在後面追趕我們。

And I had no bear spray.

我沒有防熊噴霧。

But you know, this is how forest research in Canada goes.

但是你們知道的，在加拿大的森林裡做研究就是這樣的。

(Laughter)

（笑聲）

So I came back the next day,

所以第二天，我又來了，

and mama grizzly and her cub were gone.

棕熊媽媽和她的小熊已經不在那裡了。

So this time, we really got started,

所以這次，我們可以真正開始了，

and I pulled on my white paper suit,

我穿上了白色的紙質套裝，

I put on my respirator,

我戴上了防護面罩，

and then

然後

I put the plastic bags over my trees.

我用塑膠袋包住樹。

I got my giant syringes,

我拿出巨大的注射器，

and I injected the bags

然後我向袋子中注射

with my tracer isotope carbon dioxide gases,

示蹤同位素二氧化碳氣體，

first the birch.

先注射到樺樹上。

I injected carbon-14, the radioactive gas,

我把碳14，放射性氣體，注射到

into the bag of birch.

樺樹的袋子裡。

And then for fir,

然後是杉樹，

I injected the stable isotope carbon-13 carbon dioxide gas.

我給它注射了穩定的同位素碳13二氧化碳氣體。

I used two isotopes,

我用了兩種同位素，

because I was wondering

因為我在想

whether there was two-way communication going on between these species.

在這兩類樹種之間是否有雙向的交流。

I got to the final bag,

我進行到最後一個袋子，

the 80th replicate,

第80棵樹木複本，

and all of a sudden mama grizzly showed up again.

突然，棕熊媽媽又出現了。

And she started to chase me,

她開始在後面追我，

and I had my syringes above my head,

我把注射器舉過頭頂，

and I was swatting the mosquitos, and I jumped into the truck,

我拍打著蚊子，然後跳入了卡車，

and I thought,

我想，

"This is why people do lab studies."

“這就是為什麼人們做實驗室研究。”

(Laughter)

（笑聲）

I waited an hour.

我等了一個小時。

I figured it would take this long

我想樹木應該需要這麼久的時間

for the trees to suck up the CO2 through photosynthesis,

通過光合作用吸收二氧化碳，

turn it into sugars, send it down into their roots,

把它變成糖類，輸送到它們的根部，

and maybe, I hypothesized,

也許，我猜想，

shuttle that carbon belowground to their neighbors.

還會在地下把碳輸送給它們的鄰居。

After the hour was up,

一小時過去了，

I rolled down my window,

我把車窗搖下來，

and I checked for mama grizzly.

我看看棕熊媽媽在哪裡。

Oh good, she's over there eating her huckleberries.

哦，太好了，她在那邊吃她的黑漿果。

So I got out of the truck and I got to work.

然後我從卡車裡出來，開始工作。

I went to my first bag with the birch. I pulled the bag off.

我走到第一個樺樹袋子那裡。我把袋子拿下來。

I ran my Geiger counter over its leaves.

我用我的蓋勒計數器檢測它的葉子。

Kkhh!

咔！

Perfect.

完美。

The birch had taken up the radioactive gas.

樺樹已經吸收了放射性氣體。

Then the moment of truth.

然後是檢驗真理的時刻。

I went over to the fir tree.

我走到杉樹那裡。

I pulled off its bag.

我拿下它的袋子。

I ran the Geiger counter up its needles,

我用蓋勒計數器檢測它的針狀葉子，

and I heard the most beautiful sound.

我聽到了最美的聲音。

Kkhh!

咔！

It was the sound of birch talking to fir,

那是樺樹和杉樹交談的聲音，

and birch was saying, "Hey, can I help you?"

樺樹在說：“嘿，我可以幫你嗎？”

And fir was saying, "Yeah, can you send me some of your carbon?

杉樹回答說：“可以，你能給我一些碳嗎？

Because somebody threw a shade cloth over me."

因為有人用一塊遮光布罩住了我。”

I went up to cedar, and I ran the Geiger counter over its leaves,

我走到柏樹那裡，我用蓋勒計數器檢測它的葉子，

and as I suspected,

正如我猜測的那樣，

silence.

毫無聲音。

Cedar was in its own world.

柏樹在它自己的世界裡。

It was not connected into the web interlinking birch and fir.

它沒有和聯繫著樺樹和杉樹的網絡聯繫在一起。

I was so excited,

我非常激動，

I ran from plot to plot and I checked all 80 replicates.

我從一塊地跑到另一塊地，我檢查了所有的80顆樹木複本。

The evidence was clear.

證據很明顯。

The C-13 and C-14 was showing me

碳13和碳14向我證明

that paper birch and Douglas fir were in a lively two-way conversation.

紙皮樺和黃杉進行著熱鬧的雙向的對話。

It turns out at that time of the year,

實際上，在那年的那個時候，

in the summer,

在夏天，

that birch was sending more carbon to fir than fir was sending back to birch,

樺樹給杉樹輸送的碳比杉樹輸送給樺樹的要多，

especially when the fir was shaded.

尤其是當杉樹被遮住的時候。

And then in later experiments, we found the opposite,

在以後的實驗中，我們發現了相反的結果，

that fir was sending more carbon to birch than birch was sending to fir,

杉樹給樺樹輸送的碳比樺樹輸送給杉樹的多，

and this was because the fir was still growing while the birch was leafless.

這是因為杉樹仍然在成長然而樺樹已經凋零了。

So it turns out the two species were interdependent,

這證明了這兩種樹是相互依靠的，

like yin and yang.

像陰和陽一樣。

And at that moment, everything came into focus for me.

在那一刻，一切對我而言都清晰了。

I knew I had found something big,

我知道我有了重大發現，

something that would change the way we look at how trees interact in forests,

一些會改變我們看待樹木在森林中互動方式的發現，

from not just competitors

從不僅僅是競爭者，

but to cooperators.

到合作者。

And I had found solid evidence

我找到了可靠的證據

of this massive belowground communications network,

證明這龐大的地下交流系統，

the other world.

另一個世界。

Now, I truly hoped and believed

此刻，我真心希望並相信

that my discovery would change how we practice forestry,

我的發現會改變我們實踐林學的方式，

from clear-cutting and herbiciding

從清場式伐木和大量使用除草劑，

to more holistic and sustainable methods,

到更全面，可持續的方法，

methods that were less expensive and more practical.

更廉價但是更實用的方法。

What was I thinking?

我那時在想什麼？

I'll come back to that.

我等一下會進行說明。

So how do we do science in complex systems like forests?

我們如何在像森林一樣複雜的系統中做科研？

Well, as forest scientists, we have to do our research in the forests,

嗯，作為森林科學家，我們必須在森林裡做研究，

and that's really tough, as I've shown you.

那非常艱難，正如我給你們展示的一樣。

And we have to be really good at running from bears.

我們必須非常擅長逃離熊的追趕。

But mostly, we have to persevere

但是大部分時間，我們必須堅持不懈，

in spite of all the stuff stacked against us.

即使所有的事情都對我們不利。

And we have to follow our intuition and our experiences

而且我們要跟隨我們的直覺和經驗

and ask really good questions.

問一些有價值的問題。

And then we've got to gather our data and then go verify.

然後我們需要收集數據，證實它們。

For me, I've conducted and published hundreds of experiments in the forest.

對我來說，我已經在樹林裡進行並發表了數以百計的實驗。

Some of my oldest experimental plantations are now over 30 years old.

一些我的最老的實驗基地現在已經超過30年了。

You can check them out.

你們可以去看看。

That's how forest science works.

那就是森林科學如何進展的。

So now I want to talk about the science.

現在我想談論一下科學。

How were paper birch and Douglas fir communicating?

紙皮樺和黃杉是怎樣交流的呢？

Well, it turns out they were conversing not only in the language of carbon

實際上，它們不僅僅用碳作為媒介來交流，

but also nitrogen and phosphorus

而且還用氮和磷

and water and defense signals and allele chemicals and hormones --

還有水，防禦信號，等位基因化學物質和激素 －

information.

信息。

And you know, I have to tell you, before me, scientists had thought

你們知道，我必須告訴你們，在我之前，科學家們認為

that this belowground mutualistic symbiosis called a mycorrhiza

這種地下的互惠共生，被稱作菌根，

was involved.

介入其中。

Mycorrhiza literally means "fungus root."

菌根從字面上理解是“菌類的根”。

You see their reproductive organs when you walk through the forest.

你可以看見它們的繁殖器官當你穿過森林的時候。

They're the mushrooms.

它們是蘑菇。

The mushrooms, though, are just the tip of the iceberg,

然而蘑菇只是冰山一角，

because coming out of those stems are fungal threads that form a mycelium,

因為從那些梗中長出來的是形成菌絲體的真菌絲，

and that mycelium infects and colonizes the roots

那個菌絲體會影響並且侵蝕

of all the trees and plants.

所有樹木和植物的根部。

And where the fungal cells interact with the root cells,

在真菌細胞和根細胞相互作用的地方，

there's a trade of carbon for nutrients,

會有碳和養份的交換，

and that fungus gets those nutrients by growing through the soil

而且真菌得到那些養份，通過在土壤中生長

and coating every soil particle.

並且覆蓋住每一個土壤顆粒。

The web is so dense that there can be hundreds of kilometers of mycelium

那個網絡非常密集以至於可以有長達幾百千米的菌絲體

under a single footstep.

在一個單一的足跡下面。

And not only that, that mycelium connects different individuals in the forest,

而且不僅僅是那樣，菌絲體連接著森林中不同的個體，

individuals not only of the same species but between species, like birch and fir,

不僅是同一物種的個體，還有不同物種的個體，比如樺樹和杉樹，

and it works kind of like the Internet.

它工作起來像互聯網一樣。

You see, like all networks,

要知道，像所有的網絡一樣，

mycorrhizal networks have nodes and links.

菌根網絡有節點和連結線。

We made this map by examining the short sequences of DNA

我們做了這個遺傳圖，通過研究

of every tree and every fungal individual in a patch of Douglas fir forest.

一片黃杉森林裡的每棵樹的和每個真菌體的DNA的短序列。

In this picture, the circles represent the Douglas fir, or the nodes,

在這個圖中，圓圈，或者是節點，代表黃杉，

and the lines represent the interlinking fungal highways, or the links.

直線，或者是連接線，代表相互連結的真菌幹線。

The biggest, darkest nodes are the busiest nodes.

最大的，顏色最深的節點是最繁忙的節點。

We call those hub trees,

我們把那些稱作樞紐樹，

or more fondly, mother trees,

或者更深情地叫作母親樹，

because it turns out that those hub trees nurture their young,

因為事實證明那些樞紐樹哺育它們的小樹，

the ones growing in the understory.

那些長在林下葉層的小樹。

And if you can see those yellow dots,

如果你們可以看到那些黃色的小點，

those are the young seedlings that have established within the network

那些就是在網絡中形成的幼苗，

of the old mother trees.

年邁的母親樹的網絡。

In a single forest, a mother tree can be connected to hundreds of other trees.

在一片單獨的森林中，一顆母親樹可以聯繫數以百計的其它的樹，

And using our isotope tracers,

用我們的同位素示蹤器，

we have found that mother trees

我們發現母親樹

will send their excess carbon through the mycorrhizal network

會通過真菌菌根網把它們多餘的碳送到

to the understory seedlings,

林下葉層的幼苗那裡，

and we've associated this with increased seedling survival

我們把這個行為和更高的幼苗存活率聯繫在一起，

by four times.

高達四倍的存活率。

Now, we know we all favor our own children,

現在，我們知道我們都偏向我們自己的孩子，

and I wondered, could Douglas fir recognize its own kin,

我想知道，黃杉能認出它自己的幼苗嗎，

like mama grizzly and her cub?