Off Australia’s east coast, you will find the Blue Outback, the world’s biggest structure built by living creatures – the Great Barrier Reef. But it’s surrounded by climate change and warming waters that have twice bleached (漂白) its wonderfully colored corals white.
“It really looked like Christmas, like someone had just come across and put snow over everything, ” said Perry Jones, who saw the mass bleachings firsthand in 1998 and 2002 .
The Great Barrier Reef is designated by UNESCO as a World Heritage Site. It draws millions of visitors each year. But an increase in water temperature as little as 2 degrees for just four weeks can bleach the corals, killing the algae (海藻) that give them their breathtaking colors. Worse, if the reef died, thousands of species would die out with it . since 1980, an estimated 20 percent of the world’s coral reefs have been destroyed, and the UN climate change team warns that many wonderful fish and corals could be lost as soon as 2020 if the water continues to warm.
But warmer waters aren’t the only challenge. For decades, the reef waters’ fish stocks have been used up by commercial fishing operations. And the rivers of northeastern Australia carry pollution that is swept into the reef during tropical storms.
Already, the reef authority has observed mass kills of seabirds. As warmer waters drive food fish to cooler waters, the birds have to fly farther to find food. Many don’t make it back home, and many of those do find that their chicks have died of starvation.
Higher water temperatures also affect turtle hatchlings – the higher the temperatures, the fewer males. And they threaten the habitat used by whales, for migration, calving and feeding.
Marshall, the authority’s climate change manager, said there was still time to save the Great Barrier Reef. But not much.

68. from the first paragraph, we know _________.
A. all the corals are white
B. the corals are colorful
C. the corals have no color
D. the corals are all blue
69. In Paragraph 2, Perry Jones intends to tell us that _______.
A. the corals are very beautiful
B. Christmas is drawing near
C. The pollution is too serious
D. It often snows heavily there
70. Which of the following does the greatest damage to corals?
A. fishing B. Warming waters.
C. Too many visitors. D. Not mentioned.
71. Which of the following may eventually lead to fewer male turtles ?
A. Commercial fishing operations.
B. The mass bleaching of the reefs.
C. The death of too many corals.
D. Higher water temperatures.

在澳大利亚东海岸外，你会发现一片寥无人迹的蓝色海域，那里有这个世界上最大的由活体生物构成的建筑——大堡礁。但是，变幻的气候和上升的水温将它裹胁，使它无以伦比的彩色珊瑚被两度漂白。（译注：珊瑚漂白是因为大量珊瑚死亡、骨质显露出来造成的。）

“那景象看上去就好像圣诞节一般，仿佛有人过来把雪覆盖在一切事物上面。”佩里·琼斯说道，他曾有1998年和2002年亲眼目睹大范围的珊瑚漂白。

大堡礁被联合国教科文组织确定为世界遗产，每年都吸引数百万的游人。但是，只要水温上升两度并持续四周，就能漂白珊瑚、杀死海藻，让一切变成摄人心魄的白色。更糟糕的是，如果珊瑚礁死亡，数千种生物也将随之灭绝。自1980年以来，世界上估计有20%的珊瑚礁已被破坏。联合国气候变化（研究）小组警告说，如果水温持续上升，至迟到2020年，许多奇异的鱼类和珊瑚就可能灭绝。

但上升的水温不是唯一的威胁。数十年来，珊瑚礁水域的鱼类资源被商业捕捞消耗殆尽。在热带风暴期间，澳大利亚东北部的河流会将污水排入珊瑚礁群。

珊瑚礁管理当局已经观察到海鸟的大规模死亡。升高的水温将鱼类赶入较凉的水域，鸟儿们不得不飞得更远以便捕食，许多鸟儿无力返航，还有许多鸟儿会发现它们的幼儿已经死于饥饿。

升高的水温也影响到海龟的孵化——水温越高，雄性海龟的数量就越少，并且也威胁到鲸类在迁徙、繁育和捕食等方面的生存环境。

珊瑚礁管理当局的气候变化项目经理马歇尔表示，拯救大堡礁虽然还有时间，但所剩无多。

68、从第一段，我们了解到_____。
　　A、所有的珊瑚都是白色的。
　　B、珊瑚有各种颜色。
　　C、珊瑚有无色的。
　　D、珊瑚都是蓝色的。
　　选择：B。

69、在第二段，佩里·琼斯想告诉我们_____。
　　A、珊瑚非常漂亮。
　　B、圣诞节快到了。
　　C、污染太严重了。
　　D、那里经常下雪。
　　选择：C。

70、下面哪个对珊瑚造成了最大的破坏？
　　A、捕鱼
　　B、水温上升
　　C、游客太多
　　D、文中未提及
　　选择：B。

71、下面哪个因素可能最终造成雄性海龟数量减少？
　　A、商业捕鱼行为
　　B、珊瑚礁的大量漂白
　　C、珊瑚的大量死亡
　　D、水温升高
　　选择：D。