2007年VOA标准英语-US Firm to Use Plankton to Combat Greenhouse Ga

By Brian Wagner
Miami
21 June 2007
 

Scientists are seeking new ways to reverse the buildup of carbon dioxide in the atmosphere that many believe is the cause of global warming. Today on Searching for Solutions, VOA's Brian Wagner reports that one project in the United States aimed at stimulating¹ plankton² growth in the oceans is raising some debate about its possible effectiveness.

Dumping tons of iron dust into the ocean may not appear to benefit the environment. But researchers with the U.S. firm Planktos say it is crucial to their efforts to stimulate³ plankton growth and remove carbon dioxide from the atmosphere.

Melodie Grubbs

Melodie Grubbs, a climate expert with the firm says, "Once we put that in, iron acts as a catalyst⁴ for photosynthesis⁵, which creates plankton. It's a missing nutrient⁶ in the ocean and from that sparks a natural plankton bloom."

Researchers say plankton organisms are struggling because less iron dust is being blown onto the ocean's surface by nutrient-rich winds. The Planktos team hopes to reverse the trend by seeding the waters off the Galapagos Islands and several other spots in the Pacific Ocean with a special form of iron dust.

"So we'll combine this with sea water first, concentrate it, then put it back in the ocean, and then do a zig-zag pattern to get the best coverage⁷ we can" says Grubbs describing the technique.

Like trees, plankton absorbs carbon dioxide and converts it into biomass, which can remain under water for centuries. Critics of the Planktos model, however, say it is nearly impossible to prove how much carbon dioxide is pulled from the atmosphere.

Frank Millero

Frank Millero is a professor of marine⁸ chemistry at the University of Miami. He helped pioneer research into iron fertilization in the 1990s. "The problem, if there is one, is if the carbon dioxide in the plant material does not sink to the deep waters and become oxidized there, then the net effect is not as large as you might hope for."

Millero says the team will have to continue dumping iron to trigger new plankton blooms, and he says that will be very costly⁹.

To support its efforts, Planktos hopes to get financing from major companies as a way to offset¹⁰ the greenhouse gases released through manufacturing or other activities.

The firm's Pacific project manager Michael Bailey says these carbon credits are generating new opportunities in environmental restoration. "We are part of the international carbon credit community, part of that marketing¹¹ plan, basically trying to find a way to make money by restoring the ocean's and the earth's atmosphere. So this is a beautiful business model."

Environmental experts may not agree on the best way to reverse decades of carbon dioxide emissions¹², but they do agree that more efforts are needed to remove the gas from the atmosphere.

1 stimulating   

adj.有启发性的，能激发人思考的

参考例句：

• shower gel containing plant extracts that have a stimulating effect on the skin 含有对皮肤有益的植物精华的沐浴凝胶
• This is a drug for stimulating nerves. 这是一种兴奋剂。

2 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。

3 stimulate   

vt.刺激，使兴奋；激励，使…振奋

参考例句：

• Your encouragement will stimulate me to further efforts.你的鼓励会激发我进一步努力。
• Success will stimulate the people for fresh efforts.成功能鼓舞人们去作新的努力。

4 catalyst   

n.催化剂，造成变化的人或事

参考例句：

• A catalyst is a substance which speeds up a chemical reaction.催化剂是一种能加速化学反应的物质。
• The workers'demand for better conditions was a catalyst for social change.工人们要求改善工作条件促进了社会变革。

5 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。

6 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。

7 coverage   

n.报导，保险范围，保险额，范围，覆盖

参考例句：

• There's little coverage of foreign news in the newspaper.报纸上几乎没有国外新闻报道。
• This is an insurance policy with extensive coverage.这是一项承保范围广泛的保险。

8 marine   

adj.海的；海生的；航海的；海事的；n.水兵

参考例句：

• Marine creatures are those which live in the sea. 海洋生物是生存在海里的生物。
• When the war broke out,he volunteered for the Marine Corps.战争爆发时，他自愿参加了海军陆战队。

9 costly   

adj.昂贵的，价值高的，豪华的

参考例句：

• It must be very costly to keep up a house like this.维修这么一幢房子一定很昂贵。
• This dictionary is very useful,only it is a bit costly.这本词典很有用，左不过贵了些。

10 offset   

n.分支，补偿；v.抵消，补偿

参考例句：

• Their wage increases would be offset by higher prices.他们增加的工资会被物价上涨所抵消。
• He put up his prices to offset the increased cost of materials.他提高了售价以补偿材料成本的增加。

11 marketing   

n.行销，在市场的买卖，买东西

参考例句：

• They are developing marketing network.他们正在发展销售网络。
• He often goes marketing.他经常去市场做生意。

12 emissions   

排放物( emission的名词复数 )； 散发物（尤指气体）

参考例句：

• Most scientists accept that climate change is linked to carbon emissions. 大多数科学家都相信气候变化与排放的含碳气体有关。
• Dangerous emissions radiate from plutonium. 危险的辐射物从钚放散出来。