Narrator: Listen to part of a lecture in an earth science class.

旁白：听一段地球科学的演讲。

The professor is discussing an area of the United States called the Copper Basin.

教授讨论的是美国一个叫做铜盆地的地方。

Professor: Now, you may not have heard of the Copper Basin.

教授：现在，你们可能没有听说过铜盆地。

It’s in the Eastern United States, in the Tennessee River Valley.

它位于美国东部，在田纳西河山谷。

It got its name because settlers discovered copper there in 1843.

它有这个名字是因为在1843年,在那里的定居者发现了铜。

And soon afterwards, it supported one of the largest metal mining operations in America.

在这后的不就，它就支撑了美国最大的金属矿开采作业之一。

At one time, four mining companies employed 2500 workers in the Copper Basin.

曾经，四个开采公司在铜盆地雇佣了2500个工人。

For that time period, it was a huge operation.

在那个时候，这是一个巨大的工程。

Well, this mining operation turned the Copper Basin into a desert.

这个工程将铜盆地变成了沙漠。

In the 1840s, when mining operations started, it was a dense green forest.

在1840s，当开采工程开始的时候，这里还是一个茂密的绿色森林。

But in the 1940s, 100 years later, it was as barren as the moon.

但是在1940s,100年以后，它像月亮一样贫瘠。

Efforts to reclaim the land and restore the basin to the fertile valley it once was…well, actually, those efforts are still ongoing.

回收这些土地并将这个盆地恢复到它从前那样肥沃的山谷，这样的努力到现在还在进行着。

It’s been a long and tedious process.

这是一个又长又沉闷的过程。

In fact, it was many years before any results were seen.

事实上，在有任何成果之前，需要很多年的时间去修复。

Copper mining had gone on there for more than 90 years!

铜开采在那里持续了超过90年。

The damage couldn’t be reversed overnight.

损坏是不可能在一夜之间被逆转的。

Although I should mention that by 1996, the water in one of the rivers flowing through the basin was clean enough that it was the site of the Olympic white water kayaking competition.

尽管如此，我还是要提一下到1996年为止，一条穿过盆地的河流已经足以干净到成为奥林匹克白色水域独木舟竞赛的场所。

And that river is still used now for recreation.

并且这条河仍然在消遣活动中被使用。

But…anyway…let’s analyze the problem.

但是，不管怎样，让我们来分析一下问题。

It wasn’t the mining itself that caused such massive destruction.

并不是开采本身造成了这么大的毁坏。

It was what happened after the copper ore was extracted from the mines.

毁坏发生在铜矿被提取出来以后。

It was a process called heap roasting.

这个过程被叫做堆烤。

Copper ore contains sulfur.

铜矿含有硫磺。

And heap roasting was a way to burn away the sulfur in the copper, so they’d be left with something closer to pure copper.

而堆烤就是用来将铜当中的硫磺燃烧掉的方法，这样剩下的东西就很接近纯铜。

Well, in the process, large vats of raw copper ore are burned slowly, for two or three months actually, to lower the sulfur content.

在这个过程中，大的铜矿烧的比较慢，事实上要花2-3个月去降低硫磺的成分。

And this burning, well…let’s look at the results.

这样的燃烧，好的，让我们来看一下结果会怎么样。

First, the mines were fairly remote, so there was no way to bring coal or other fuel to keep the fires going.

首先，矿山一般都比较远，所以没有方法去把煤或者其他一些燃料带来，去保持火一直燃烧。

So they cut down local trees for fuel.

因此，他们砍了当地的树木当做燃料。

And like I said, the fires burned for months.

就想我说过的，这样的火要持续数月。

Uh…that’s a lot of fires and a lot of trees.

那就意味着很多火和很多棵树。

Deforestation was occurring at a rapid rate.

森林采伐快速地增长。

And it was accelerated by the smoke from the burning ore.

焚烧矿石的烟雾也加速了这个过程。

Big clouds of sulfuric smoke, which was toxic to the trees, formed over the areas.

对树木有毒的硫磺烟雾云团在这个地方形成。

Trees that hadn’t been cut for fuel were killed by the fumes.

还未被砍伐用作燃料的树木被这个烟气所毒死。

The sulfur also mixed with the air and created sulfur dioxide.

硫磺也会和空气混合，形成二氧化硫。

And the sulfur dioxide settled in the clouds fell to the land in droplets of rain and sank into the soil.

然后在云团中的二氧化硫在雨滴中降落到地面上，并渗透到土壤中。

This is what we now call acid rain.

现在我们称为酸雨。

You’ve probably heard of it.

你可能听过它。

But no one used the term back then.

当时没有人这样称呼它。

Anyway…the acid rain created highly acidic soil.

不管怎样……酸雨造成了强酸性的土地。

Well, soon the soil became so acidic that nothing could grow, nothing at all.

很快的这土地就变得酸性太强，以至于没有什么可以在上面生长。

Vegetation and wild life disappeared.

植被和野生动物都消失了。

And it wasn’t just the land and the air, it was the water too.

但是这样的破坏不仅仅发生在土地或者空气中，水也受到了破坏。

What do you think happen to the rivers?

你觉得河流发生了什么？

Well, there are no trees to absorb the rain, and there was a lot of rain.

没有树木可以吸收雨水，那么就有大量的雨水。

So the rain eroded the soil and swept it into the rivers.

所以雨水侵蚀了土壤，并且将它冲刷到河流里去。

This is called silting, when soil particles are washed into the rivers.

当土壤颗粒被冲到河流里面去，就被称作为淤积。

And the silting continued at an alarming rate.

并且这样的淤积以惊人的速度持续着。

But this was toxic soil and toxic runoff, the acid and metals in the soil made the once clear rivers flow bright orange.

但是这是有毒的土壤和径流，在土壤中的酸和金属使得一度清澈的河流变得橙黄。

So it was really that one step in the process of producing copper…the problems just built up and up until there was a desert where a beautiful forest used to be.

所以，这真的是在制铜过程中的一步……问题越来越严重直到原来美丽的森林变成沙漠。

OK. Now let’s look at reforestation and land reclamation efforts.

好的。现在我们来看一下重造森林和土地开垦的努力。