Take away trees, and there's less transpiration.

树木变少了，蒸腾作用就会减少。

This is so that they don't lose too much water through transpiration.

这样它们就不会因为蒸腾作用而损失太多水分。

The trees in the Amazon rain forest recycle precipitation through a process called transpiration.

亚马逊雨林里的树木通过蒸腾作用来进行降水再循环。

Eventually, evaporation and plant transpiration release water back into the atmosphere where it becomes precipitation again.

最，蒸发和植物蒸腾作用会将水分释放到大气中，再次成为降水。

This evaporation, called transpiration, creates negative pressure in the xylem, pulling watery xylem sap up the tree.

这种蒸发，叫作蒸腾作用，在木质中产生一种负压，把液体的木质树液往树上方拉。

To understand this, first, you need to know about a process called transpiration, sometimes called the evapotranspiration.

要理解这一点，首先，你需要了解一个叫做蒸腾作用的过程，有时也叫蒸散作用。

To accomplish this herculean task, the xylem relies on three forces: transpiration, capillary action, and root pressure.

要完成这样艰巨的任务，木质要依赖于三种力量：蒸腾作用，毛细作用和根压。

Transpiration is just sweating, so let's just say sweat.

蒸腾作用就是出汗, 所以就说出汗吧。

After absorbing rain through their roots, they release water vapor into the air through their leaves in a process called transpiration.

在根部吸收雨水后，它们会在一个叫蒸腾作用的过程中通过树叶把水蒸气释放进空气中。

Look, here's a picture of part of the Amazon rainforest, you'll notice you can barely see anything through the layer of numerous small clouds created by transpiration.

看，这是一张亚马逊雨林一角的照片，你会注意到透过由蒸腾作用产生的无数小云层，你几乎看不到任何东西。