福克斯新闻 地球上有3万亿棵树 比史前减少数万亿棵

There are now more than 3 trillion trees growing on Earth, which is seven times more than scientists previously¹ thought.

That said, there are also trillions fewer than there used to be.

The leafy findings are from a study published Wednesday in the journal Nature by Yale forestry² researcher Thomas Crowther.

Crowther and his colleagues used 429,775 ground based measurements with satellite measurements and computer models for the count.

But with people cutting down 15 billion trees a year, and only 5 billion replanted, Crowther says Earth's trees could be gone in about 300 years.

地球上目前生长着超过3万亿棵树木，是科学家们此前所认为的树木数量的7倍。

也就是说，这也比曾经的树木数量少了数万亿棵。

美国耶鲁大学的林业研究人员托马斯·克劳瑟在英国《自然》周刊发表的一项研究报告中得出了这样的结论。

克劳瑟和他的同事们利用陆基测量，卫星测量及计算机模型模拟演算得到了更为精确的数字，429,775。

但随着每年人们砍伐150亿棵树,只有50亿棵树重新种植, 克劳瑟表示地球上的树木可能在300年内消失。

1 previously   

adv.以前，先前（地）

参考例句：

• The bicycle tyre blew out at a previously damaged point.自行车胎在以前损坏过的地方又爆开了。
• Let me digress for a moment and explain what had happened previously.让我岔开一会儿，解释原先发生了什么。

2 forestry   

n.森林学；林业

参考例句：

• At present, the Chinese forestry is being at a significant transforming period. 当前, 我国的林业正处于一个重大的转折时期。
• Anhua is one of the key forestry counties in Hunan province. 安化县是湖南省重点林区县之一。