英语听力：自然百科 佛罗里达州的温泉（二）

 The divers¹ started in the ocean, but they are now within solid bedrock, 150 feet beneath someone's living room. They are now swimming in the water supply for the town above. Here they find, as they had hoped, life in the pitch darkness. These are hydroids, small filter-feeding organisms, a species entirely² new to science. Around the hydroids are mussels. Neither of them are found in the springs above. Both are anchored to the rock and live on food that drifts by. But there is no apparent sign of food and no energy to create it. In almost every living system, the sun provides fuel for all life. But there is no sunlight here, how these organisms kept alive?

 

With such exciting discoveries, the team decides to press on, but time and air are finite. Their air is consumed quickly at this depth and each minute they stay will increase the time they must spend decompressing before they can leave the water. The slightest turbulence³ stirs up sediment⁴ which can render visibility from hundreds of feet to nearly zero. Then, 3,000 feet into the springs, they make an extraordinary discovery--a strange layer of water.

 

The layer below is saltwater but clear, fresh water flows above. Where the layers meet, there is a thin, cloudy substance that they have never seen before. Later analysis reveals it to be bacteria. It lives on a microscopic⁵ horizon between fresh and saltwater. It is this bateria which provides the basis for all life in the cave. The bacteria metabolizes sulfur⁶ from the water and multiplies. In turn, the bacteria becomes food for the mussels and hydroids downstream. In this cave, lowly bacteria takes the place of sunlight and starts the chain of life.

 

The divers christen the cave of their discovery "the dragon's lair⁷" in honor of its unique smoky resident. It's a shock to realize that there is so much life within the town's water supply. But it's probably an indicator⁸ of healthy water. If the life here vanishes, maybe then we should worry about the quality of our drinking water.

1 divers   

adj.不同的；种种的

参考例句：

• He chose divers of them,who were asked to accompany him.他选择他们当中的几个人，要他们和他作伴。
• Two divers work together while a standby diver remains on the surface.两名潜水员协同工作，同时有一名候补潜水员留在水面上。

2 entirely   

ad.全部地，完整地；完全地，彻底地

参考例句：

• The fire was entirely caused by their neglect of duty. 那场火灾完全是由于他们失职而引起的。
• His life was entirely given up to the educational work. 他的一生统统献给了教育工作。

3 turbulence   

n.喧嚣，狂暴，骚乱，湍流

参考例句：

• The turbulence caused the plane to turn over.空气的激流导致飞机翻转。
• The world advances amidst turbulence.世界在动荡中前进。

4 sediment   

n.沉淀，沉渣，沉积(物)

参考例句：

• The sediment settled and the water was clear.杂质沉淀后，水变清了。
• Sediment begins to choke the channel's opening.沉积物开始淤塞河道口。

5 microscopic   

adj.微小的，细微的，极小的，显微的

参考例句：

• It's impossible to read his microscopic handwriting.不可能看清他那极小的书写字迹。
• A plant's lungs are the microscopic pores in its leaves.植物的肺就是其叶片上微细的气孔。

6 sulfur   

n.硫，硫磺（=sulphur）

参考例句：

• Sulfur emissions from steel mills become acid rain.炼钢厂排放出的硫形成了酸雨。
• Burning may produce sulfur oxides.燃烧可能会产生硫氧化物。

7 lair   

n.野兽的巢穴；躲藏处

参考例句：

• How can you catch tiger cubs without entering the tiger's lair?不入虎穴，焉得虎子？
• I retired to my lair,and wrote some letters.我回到自己的躲藏处，写了几封信。

8 indicator   

n.指标；指示物，指示者；指示器

参考例句：

• Gold prices are often seen as an indicator of inflation.黃金价格常常被看作是通货膨胀的指标。
• His left-hand indicator is flashing.他左手边的转向灯正在闪亮。