VOA常速英语2007年-Scientists Fear Amazon May Face Early Destructi

By Trish Anderton
Bali, Indonesia
12 December 2007

Researchers in the Amazon, attending the United Nations Conference on Climate Change in Bali, say a vicious cycle of climate change and deforestation could destroy the world's largest tropical rain forest more quickly than expected. Trish Anderton explains, in a background report.

Researcher Dan Nepstad calls it a "perfect storm" of deforestation: as fire and ranching¹ destroy the Amazon forest in Brazil, the remaining trees release less moisture, producing a dryer² climate that kills more trees. It adds up to a vicious cycle of destruction.

A World Bank-funded study released early this year predicted the Amazon could become a grassy³ savannah by the end of the century.

Nepstad produced a report for the World Wildlife Fund or WWF that was released at the Bali climate change conference. He says substantial destruction could come much sooner than that.

"If we add these processes up, we see that by 2030 - not by the end of the century but in the next two and a half decades - given current trends, 55 percent of the forests of the Amazon will have been cleared or impoverished⁴ through some combination of logging, drought and fire," said Nepstad.

Living trees absorb carbon, and many scientists believe the release of carbon into the atmosphere is warming the planet and fueling global climate change.

Nepstad says a widespread death of trees in the Amazon of the scale he is predicting would release up to 26 billion tons of carbon, or as much as the whole planet produces in about two and a half years.

Antonio Nobre of Brazil's National Institute for Research in the Amazon says signs of a destructive climate cycle are already detectable⁵.

"What we are seeing already in southern Brazil, which is in the wake of the river of water vapor⁶ coming from the Amazon, is already a drying up. We have analyzed⁷ just ten years but you see clearly a tendency of drying," said Nobre.

Christiane Ehringhaus, who studies the Amazon for the Center for International Forestry⁸ Research, says she would not be surprised if the Amazon's future is bleaker⁹ than previously¹⁰ expected. She says the cycle of drying may have contributed to, and been intensified¹¹ by, widespread forest fires in 2005.

"You saw fires in areas of the Amazon that hadn't been detected even as flammable in previous models. So you saw forest fires that are undetectable from space that do tremendous damage and dry up the forest for subsequent fires," said Ehringhaus.

The WWF report says much of the destruction results from burning of the forest to clear land, which is then used to meet the global demand for soybeans, beef and biofuel. It says one way to help preserve the forest is to strengthen existing government land-use policies and programs.

Nepstad praises recent efforts by Brazil to create conservation areas.

"We see enormous successes the Brazilian government has made in creating protected areas in the pathway of the expanding agro-industrial frontier - 23 million hectares of new areas protected in the two-year period beginning in early 2004," he said.

Even so, the report says the prediction of substantial damage by 2030 is conservative. It urges a reforesting of cleared areas and promotion¹² of reduced-impact logging and sustainable agriculture, to slow or reverse damage to the rain forest.

Eduardo Bandeira de Mello of the Brazilian Development Bank says his bank is trying to fund such efforts.

"We can finance the states of the Amazon region in order to have institutional strengthening to be more proactive in fighting against deforestation, and we can finance alternative projects in the deforestation belt," said de Mello.

Besides absorbing heat from sunlight and converting it into cooling water vapor, the Amazon provides as much as one-fifth of the earth's river water. It is one of the world's most biologically diverse regions.

1 ranching   

adj.放牧的

参考例句：

• They cleared large tracts of forest for farming, logging and ranching. 他们清除了大片的森林以经营农耕、采伐与畜牧。
• This is a trade center in a ranching and oil-producing region. 这是一个牧场与产油区的贸易中心。

2 dryer   

n.干衣机，干燥剂

参考例句：

• He bought a dryer yesterday.他昨天买了一台干燥机。
• There is a washer and a dryer in the basement.地下室里有洗衣机和烘干机。

3 grassy   

adj.盖满草的；长满草的

参考例句：

• They sat and had their lunch on a grassy hillside.他们坐在长满草的山坡上吃午饭。
• Cattle move freely across the grassy plain.牛群自由自在地走过草原。

4 impoverished   

adj.穷困的，无力的，用尽了的v.使（某人）贫穷( impoverish的过去式和过去分词 )；使（某物）贫瘠或恶化

参考例句：

• the impoverished areas of the city 这个城市的贫民区
• They were impoverished by a prolonged spell of unemployment. 他们因长期失业而一贫如洗。 来自《简明英汉词典》

5 detectable   

adj.可发觉的；可查明的

参考例句：

• The noise is barely detectable by the human ear.人的耳朵几乎是察觉不到这种噪音的。
• The inflection point at this PH is barely detectable.在此PH值下，拐点不易发现。

6 vapor   

n.蒸汽，雾气

参考例句：

• The cold wind condenses vapor into rain.冷风使水蒸气凝结成雨。
• This new machine sometimes transpires a lot of hot vapor.这部机器有时排出大量的热气。

7 analyzed   

v.分析( analyze的过去式和过去分词 )；分解；解释；对…进行心理分析

参考例句：

• The doctors analyzed the blood sample for anemia. 医生们分析了贫血的血样。 来自《简明英汉词典》
• The young man did not analyze the process of his captivation and enrapturement, for love to him was a mystery and could not be analyzed. 这年轻人没有分析自己蛊惑著迷的过程，因为对他来说，爱是个不可分析的迷。 来自《简明英汉词典》

8 forestry   

n.森林学；林业

参考例句：

• At present, the Chinese forestry is being at a significant transforming period. 当前, 我国的林业正处于一个重大的转折时期。
• Anhua is one of the key forestry counties in Hunan province. 安化县是湖南省重点林区县之一。

9 bleaker   

阴冷的( bleak的比较级 )； （状况）无望的； 没有希望的； 光秃的

参考例句：

• Horoscopes are merely harmless escapism from an ever-bleaker world. 占星术只不过是让人逃避越发令人沮丧的世界的无害消遣罢了。
• On the ground the mood is bleaker. 具体形势更加严峻。

10 previously   

adv.以前，先前（地）

参考例句：

• The bicycle tyre blew out at a previously damaged point.自行车胎在以前损坏过的地方又爆开了。
• Let me digress for a moment and explain what had happened previously.让我岔开一会儿，解释原先发生了什么。

11 intensified   

v.（使）增强， （使）加剧( intensify的过去式和过去分词 )

参考例句：

• Violence intensified during the night. 在夜间暴力活动加剧了。
• The drought has intensified. 旱情加剧了。 来自《简明英汉词典》

12 promotion   

n.提升，晋级；促销，宣传

参考例句：

• The teacher conferred with the principal about Dick's promotion.教师与校长商谈了迪克的升级问题。
• The clerk was given a promotion and an increase in salary.那个职员升了级，加了薪。