PTE考生目前最大的问题之一就是练习题缺乏。除了有限的基本官方书（PLUS，Testbuilder, OG）之外就没有题了。很多英语基础不是很扎实的同学很难找到练习材料。悉尼文波雅思PTE培训学校专门为澳洲，尤其是悉尼、墨尔本的PTE考生准备了适合PTE听力阅读练习的科学60秒。各位PTE同学可以练习PTE听力中的summarise spoken text和PTE口语中的retell lecture，PTE听力口语-科学60秒-Frosty Moss练习记笔记技巧和复述。废话少说，下面开始：
60秒科学:Do Rainforests Create Rain?
Rainforests exist because it rains a lot and that makes the forests grow, right? Well, not so fast. What if it’s not the rain that makes the forests—what if it’s the forests that actually generate the rain? That’s the contention of a paper in BioScience Magazine called How Forests Attract Rain.
The article discusses a mostly overlooked hypothesis that, if right, would explain how big rainforests—like the Amazon—actually drive the entire global water cycle.
Here’s the idea. Forests pull in large amounts of water vapor from surrounding regions and from nearby bodies of water. As the vapor condenses into rain, the local atmospheric pressure drops. Which sucks in more water vapor from outside the forest. Which repeats the process. Creating a positive feedback loop. The whole rainforest-water vapor system is called a biotic pump, because the living forest matter is what’s moving the water.
If proven, the biotic-pump hypothesis could explain how big rainforests far from oceans stay so moist. The info would help climate models. And highlight the potential dangers of deforesting large parts of the pump.
—Steve Mirsky
