Trees are majestic, help biodiversity and can reduce climate change.

樹木很壯麗、幫助生物多樣性及減輕氣候變遷。

But we're cutting them down at an alarming rate.

但我們正以驚人的速度砍伐它們。

Since the start of human civilisation, its estimated that we've cut down almost half the trees on Earth.

自從人類文明起源，估計我們已經砍掉地表上將近一半的樹木。

So, what would happen if all of us—and that's all 7.7 billion of us—planted a tree?

所以，如果我們所有人，所有 77 億人，一人種下一棵樹會怎麼樣呢？

Well, there might be 7.7 billion of us, but it's estimated there are currently over three trillion trees on the planet.

雖然我們有 77 億人，但是地球上估計有超過 3 兆棵樹木。

7.7 billion more trees would be a valuable step forward.

種下 77 億棵樹會是幫助環境很珍貴的一步。

But we'd need to go further to make a really substantial difference to the environment.

但我們必須做出更多事情才能為環境帶來永續的改變。

But we could.

但我們是可以做到的。

In fact, according to one estimate, if we planted 1.2 trillion trees, we'd cancel out a decade's worth of CO2 emissions by the time the forests mature.

實際上，根據預估，如果我們種下 1.2 兆棵樹，在森林成熟時可以消掉 10 年的二氧化碳排放量。

So that's more like 160 trees per person.

而換算下來約是一人種下 160 棵樹。

Trees take carbon dioxide out of the air and release oxygen, making them a natural source of carbon capture.

樹木吸收大氣裡的二氧化碳並釋出氧氣，使得它們成為一個天然的固碳來源。

Planting 1.2 trillion more trees could capture up to 100 gigatons of CO2, on top of the 400 gigatons captured by all our existing trees.

種植 1.2 兆多棵樹可以固定住達 100 兆噸的二氧化碳，而全部樹木加起來最多可以固定住 400 兆的二氧化碳。

Trees planted near the equator can be especially beneficial, as they grow much faster in the warm, wet, and humid environment.

在赤道附近植樹尤其有效，因為樹木在溫暖潮濕的環境中生長較快。

Let's imagine that happened.

讓我們想像一下這一切的發生。

In as little as 20 or 30 years, entire woodlands and forests would be established.

只要 20 或 30 年，林地和森林都會成型。

And in 100 years, these trees would grow and mature, safeguarding habitats that otherwise get cut down.

然後 100 年後，這些樹木會生長成熟，保護了原本將被砍伐殆盡的棲地。

We'd also see a rise in biodiversity as trees get older and start to decompose, because they, along with dead trees, offer a habitat to all kinds of fungi and insects.

當樹木老去並開始腐爛的同時也會見證生物多樣性的成長，因為這些枯木提供了各種菌類及昆蟲的棲地。

On top of this, we could see a positive impact to our mental health, as studies have shown trees can lower stress and make people happier.

更重要的是，我們可以看到林木對於我們心理健康所帶來的正面影響，有研究顯示樹木可以降低壓力、使人更快樂。

In Japan, they have a term for it, "forest bathing."

在日本，他們對此有一個用法，「森林浴」。

But despite how much trees offer us, we're getting rid of them at an alarming rate.

但儘管樹木對我們提供了很多幫助，我們正以令人擔憂的速度將他們砍伐殆盡。

Currently, it's estimated that 15 percent of all greenhouse gas emissions are the result of deforestation, because when we cut down trees they emit carbon instead of absorbing it.

近期估計有百分之十五的溫室氣體排放是因為去森林化所導致，因為當我們砍樹時，它們會排出碳而不是吸收碳。

And we're cutting down 15 billion trees a year, that's almost 500 trees a second, 29,000 a minute, 1.7 million an hour, 41 million a day.

而我們一年要砍掉 150 億棵樹，換算下來幾乎是每秒 500 棵、一分鐘 29000 棵、每小時 170 萬棵、每天 4100 萬棵。

So, although tree planting is a valuable part of tackling climate change, it won't be effective unless we reduce the number we cut down in the first place and make big changes to the way we live.

所以，雖然種樹是對抗氣候變遷很重要的一部分，但除非我們先減少砍伐量與改變生活習慣，不然一切都是枉然。

So, if everyone on the planet planted a single tree, it would be a powerful symbolic act.

所以，如果地球上所有人都種下一棵樹，將會是一個強而有力的象徵性行為。

And if we kept on planting them and stopped cutting them down, it could go a long way to protecting and safeguarding our world.

而且如果我們持續種樹和停止砍伐，將能長久地守護我們的世界。

Thanks for watching.

謝謝收看。

Don't forget to subscribe and click the bell to receive notifications for new videos.

不要記得按下訂閱及小鈴鐺來接收任何新影片的資訊。

See you again soon!

我們下次再見！