国家地理-2008-07-28 温室效应导致花种减少

In the Rocky Mountains of Central Colorado, the forces of nature create a landscape of alpine¹ lakes, high-altitude ponds teeming² with life and mountain meadows bursting with wild flowers. It is amidst these beautiful wildflower fields that one scientist has already found alarming evidence about the potential impact of global warming. John Hart, a professor of Environmental Science at the University of California, Berkley, runs an experiment to determine what would happen if the temperature was just three degrees warmer here year around, like the forecasted effect of global warming.

 “That heating effect will induce dramatic effects on these subalpine meadows, causing loss of plant seed we especially value here, the flowering plants.”

 John Hart has come here each summer since the 1970s, examining factors affecting life in this fragile ecosystem³.

 “This heating is actually quite subtle. We are not heating a lot. It’s only a few degrees, but it’s causing the flowering plants to produce fewer flowers and to grow less abundantly.”

 His setup is relatively⁴ simple. Low-power electric heaters suspended above a mountain meadow heat the ground and the plant life beneath, three degrees warmer than the surrounding area. The heaters are automatically and precisely⁵ controlled, they have been on constantly, day and night, winter, spring, summer and fall since 1991. In his global warming experiment, he suspended heaters in a grid⁶ pattern to create heated plots, then unheated plots, back and forth⁷, so he can judge the effects side by side. The difference, three degrees of separation makes in flowers and sagebrush, is easy to see.

 “They suck juices out of the plant.”

In the unheated natural area, sagebrush is a source of moisture for an army of thirsty insects. They keep sagebrush under control.

 “So they have little mouthpieces that can suck away at the nutrient⁸.”

 But just a few feet away, sagebrush under the heater grows far better with fewer bugs⁹.

 “...much more rapidly, we found that the heating is causing profuse¹⁰ growth of the sagebrush.”

 While that’s good for the sagebrush; it’s not good for its plant neighbors. Flowers feel the effect too. In natural areas, flowers grow thick as they always do here, but a few feet away, where it’s three degrees warmer, flowers are not as abundant.

 “The meadows, instead of looking lush and strewn with flowers, are now actually rather arid¹¹.”

 If global warming, or long-term climate change, does increase the year-around temperature here just a few degrees, John Hart predicts, in decades to come, flowers could be crowded out by sagebrush.

 “Global warming is more than just an ecological¹² catastrophe¹³; it would be a human catastrophe in all of its dimensions.”

1 alpine   

adj.高山的；n.高山植物

参考例句：

• Alpine flowers are abundant there.那里有很多高山地带的花。
• Its main attractions are alpine lakes and waterfalls .它以高山湖泊和瀑布群为主要特色。

2 teeming   

adj.丰富的v.充满( teem的现在分词 )；到处都是；（指水、雨等）暴降；倾注

参考例句：

• The rain was teeming down. 大雨倾盆而下。
• the teeming streets of the city 熙熙攘攘的城市街道

3 ecosystem   

n.生态系统

参考例句：

• This destroyed the ecosystem of the island.这样破坏了岛上的生态系统。
• We all have an interest in maintaining the integrity of the ecosystem.维持生态系统的完整是我们共同的利益。

4 relatively   

adv.比较...地，相对地

参考例句：

• The rabbit is a relatively recent introduction in Australia.兔子是相对较新引入澳大利亚的物种。
• The operation was relatively painless.手术相对来说不痛。

5 precisely   

adv.恰好，正好，精确地，细致地

参考例句：

• It's precisely that sort of slick sales-talk that I mistrust.我不相信的正是那种油腔滑调的推销宣传。
• The man adjusted very precisely.那个人调得很准。

6 grid   

n.高压输电线路网；地图坐标方格；格栅

参考例句：

• In this application,the carrier is used to encapsulate the grid.在这种情况下，要用载体把格栅密封起来。
• Modern gauges consist of metal foil in the form of a grid.现代应变仪则由网格形式的金属片组成。

7 forth   

adv.向前；向外，往外

参考例句：

• The wind moved the trees gently back and forth.风吹得树轻轻地来回摇晃。
• He gave forth a series of works in rapid succession.他很快连续发表了一系列的作品。

8 nutrient   

adj.营养的，滋养的；n.营养物，营养品

参考例句：

• Magnesium is the nutrient element in plant growth.镁是植物生长的营养要素。
• The roots transmit moisture and nutrient to the trunk and branches.根将水分和养料输送到干和枝。

9 bugs   

adj.疯狂的，发疯的n.窃听器( bug的名词复数 )；病菌；虫子；[计算机]（制作软件程序所产生的意料不到的）错误

参考例句：

• All programs have bugs and need endless refinement. 所有的程序都有漏洞，都需要不断改进。 来自《简明英汉词典》
• The sacks of rice were swarming with bugs. 一袋袋的米里长满了虫子。 来自《简明英汉词典》

10 profuse   

adj.很多的，大量的，极其丰富的

参考例句：

• The hostess is profuse in her hospitality.女主人招待得十分周到。
• There was a profuse crop of hair impending over the top of his face.一大绺头发垂在他额头上。

11 arid   

adj.干旱的；(土地)贫瘠的

参考例句：

• These trees will shield off arid winds and protect the fields.这些树能挡住旱风,保护农田。
• There are serious problems of land degradation in some arid zones.在一些干旱地带存在严重的土地退化问题。

12 ecological   

adj.生态的，生态学的

参考例句：

• The region has been declared an ecological disaster zone.这个地区已经宣布为生态灾难区。
• Each animal has its ecological niche.每种动物都有自己的生态位.

13 catastrophe   

n.大灾难，大祸

参考例句：

• I owe it to you that I survived the catastrophe.亏得你我才大难不死。
• This is a catastrophe beyond human control.这是一场人类无法控制的灾难。