英语听力：自然百科 大堡礁 堡礁内外(24)

This bleaching¹ occurs because corals can only live in a narrow temperature range.

这种漂白现象之所以发生是因为珊瑚虫只能在很窄的气温范围内存活。

Healthy corals get their colour from microscopic² algae³ living in their tissues.

健康的珊瑚虫颜色来自于生活它们组织里的海藻。

These manufacture food for the corals by photosynthesis⁴ but when the temperature rises just two degrees above the normal summer maximum, the algal cells are expelled because they no longer benefit the coral.

这些海藻通过光合作用为珊瑚虫生产食物，但是当气温上升，仅仅比夏天正常的最高气温高两度海藻细胞就会被排出，因为它们不在对珊瑚有用处。

The bleaching effect is the white chalky skeleton showing through the coral's transparent⁵ tissues.

漂白效应是珊瑚白色的骨骼，透过透明的组织显露出来。

But they're not dead. Not yet.

但是它们没有死亡。

They can survive in this bleached⁶ state for several weeks.

它们能在这种漂白状态下生存几个星期。

If the temperature drops,the corals acquire new algae from plankton⁷ floating by.

如果气温下降，珊瑚从游过的浮游生物获得新的海藻。

But, if the warm water persists, the coral dies.

但是如果水温继续保持下去，珊瑚就会死亡。

Coral bleaching hadn't been seen on the Great Barrier Reef before the 1980s.

在大堡礁珊瑚礁变白现象在19世纪80年代之前，没有被看到过。

Due to global warming, bleaching's now more common and cyclones⁸ are likely to be more frequent too.

由于全球变暖，珊瑚礁变白变得更普遍，飓风也变得更频繁了。

And there's something even more insidious⁹.

有一些事情有着更严重的潜在危险。

Temperatures are rising because more and more carbon dioxide from human activity enters the atmosphere.

气温上升是由于人类活动导致越来越多的，二氧化碳进入到大气。

This dissolves in seawater turning it weakly acidic,which can stop coral growth.

它们溶解到海水中导致海水轻微变酸，这能导致珊瑚礁停止生长。

If they can't build their chalky skeletons,reefs will start to crumble¹⁰.

如果它们不能建造它们的骨骼，珊瑚礁将会开始慢慢垮掉。

1 bleaching   

漂白法，漂白

参考例句：

• Moderately weathered rock showed more intense bleaching and fissuring in the feldspars. 中等风化岩石则是指长石有更为强烈的变白现象和裂纹现象。
• Bleaching effects are very strong and show on air photos. 退色效应非常强烈，并且反映在航空象片上。

2 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。

3 algae   

n.水藻，海藻

参考例句：

• Most algae live in water.多数藻类生长在水中。
• Algae grow and spread quickly in the lake.湖中水藻滋蔓。

4 photosynthesis   

n.光合作用

参考例句：

• In apple trees photosynthesis occurs almost exclusively in the leaves.苹果树的光合作用几乎只发生在叶内。
• Chloroplasts are the structures in which photosynthesis happens.叶绿体就是光合作用发生的地方。

5 transparent   

adj.明显的，无疑的；透明的

参考例句：

• The water is so transparent that we can see the fishes swimming.水清澈透明，可以看到鱼儿游来游去。
• The window glass is transparent.窗玻璃是透明的。

6 bleached   

漂白的，晒白的，颜色变浅的

参考例句：

• His hair was bleached by the sun . 他的头发被太阳晒得发白。
• The sun has bleached her yellow skirt. 阳光把她的黄裙子晒得褪色了。

7 plankton   

n.浮游生物

参考例句：

• Plankton is at the bottom of the marine food chain.浮游生物处于海洋食物链的最底层。
• The plankton in the sea feeds many kinds of animals. 海的浮游生物成为很多种动物的食物。

8 cyclones   

n.气旋( cyclone的名词复数 )；旋风；飓风；暴风

参考例句：

• The pricipal objective in designing cyclones is to create a vortex. 设计旋风除尘器的主要目的在于造成涡旋运动。 来自辞典例句
• Middle-latitude cyclones originate at the popar front. 中纬度地区的气旋发源于极锋。 来自辞典例句

9 insidious   

adj.阴险的，隐匿的，暗中为害的，（疾病）不知不觉之间加剧

参考例句：

• That insidious man bad-mouthed me to almost everyone else.那个阴险的家伙几乎见人便说我的坏话。
• Organized crime has an insidious influence on all who come into contact with it.所有和集团犯罪有关的人都会不知不觉地受坏影响。

10 crumble   

vi.碎裂，崩溃；vt.弄碎，摧毁

参考例句：

• Opposition more or less crumbled away.反对势力差不多都瓦解了。
• Even if the seas go dry and rocks crumble,my will will remain firm.纵然海枯石烂，意志永不动摇。