Traditional scientific techniques couldn't parse environmental samples containing mixed genetic material from multiple species.

传统的技术无法解析环境的样本，如果样本混合了多种生物的遗传物质。

Mixed materials of this sort are hard to recycle, and therefore end up being dumped in landfill, or incinerated.

这种混合材料很难回收，因此最终会被扔到垃圾填埋场或者焚烧。

The ancient builders mixed materials like burnt limestone and volcanic sand with water and gravel, creating chemical reactions to tie everything together.

古代建筑者将烧焦的石灰岩和火山砂等材料与水和砾石混合，产生化学反应，从而将所有物质粘合在一起。

And so at the end, you'll see where it's darker and just more mixed material, but that's what ultimately becomes the compost.

最后，你会看到那里的颜色比较暗，混合的物质比较多，但这就是最终成为堆肥的东西。