Question

    Tiny microbes(微生物) are at the heart of a new agricultural technique to manage harmful greenhouse gas. Scientists have discovered how microbes can be used to turn carbon dioxide into soil-enriching limestone(石灰石), with the help of a type of tree that grows in tropical areas, such as West Africa.

Researchers have found that when the Iroko tree is grown in dry, acidic soil and treated with a combination of natural fungi(霉菌) and other bacteria, not only does the tree grow well, it also produces the mineral limestone in the soil around its root.

The Iroko tree makes a mineral by combining Ca from the earth with CO₂ from the atmosphere. The bacteria then create the conditions under which this mineral turns into limestone. The discovery offers a new way to lock carbon into the soil, keeping it out of the atmosphere. In addition to storing carbon in the trees’ leaves and in the form of limestone, the mineral in the soil makes it more suitable for agriculture.

The discovery could lead to reforestation(重新造林) projects in tropical countries, and help reduce carbon dioxide in the atmosphere in the developing world. It has already been used in West Africa and is being tested in Bolivia, Haiti and India.

The findings were made in a three-year project involving researchers from the Universities of Edinburgh, Granada, Lausanne and Delft University of Technology. The project examined several microbiological methods of locking CO₂ as limestone, and the Iroko-bacteria way showed best results. Work was funded by the European Commission under the Future&Emerging Technologies(FET) scheme.

Dr Bryne Ngwenya of the University of Edinburgh’s School of GeoSciences, who led the research, said:“By taking advantage of this natural limestone-producing process, we have a low-tech, safe, readily employed and easily operating way to lock carbon out of the atmosphere, while improving farming conditions in tropical countries.”

1.The passage is mainly introducing        .

A. some useful natural fungi and bacteria

B. a new way to deal with greenhouse gas

C. a newly-found tree in West Africa

D. the soil-enriching limestone created by scientists

2.Which of the following is True about tiny microbes?

A. Most tiny microbes like living in dry, acidic soil.

B. CO₂ can be broken down by natural fungi and bacteria.

C. The more greenhouse gas is, the more active tiny microbes become.

D. Tiny microbes get along well with the Iroko tree in special soil.

3.What does the underlined word “it” in paragraph 3 probably refer to?

A. Carbon dioxide.

B. Carbon.

C. Soil.

D. Limestone.

4.According to the passage, what can we infer?

A. The action of the tiny microbes can increase the oxygen in the earth.

B. Researchers have done the experiment on trees in Africa for three years.

C. Researchers tend to use natural power to solve their problem.

D. West Africa is one of the most polluted areas all over the world.

5.According to the passage, the Iroko-bacteria method        .

A. can be used to improve the farming land

B. can save a lot of seriously destroyed woods

C. has been popularized in Bolivia, Haiti and India

D. should be spread all around the world in the future

Answer

1.B

2.D

3.C

4.C

5.A

【解析】

本文是一篇说明文，介绍了科学家发现在艾罗科树的帮助下，微生物可以用来将二氧化碳转化为石灰石，这种方法可以用来处理温室气体。

1.主旨大意题。根据第一段中的“Tiny microbes(微生物) are at the heart of a new agricultural technique to manage harmful greenhouse gas.”可知，微生物是管理有害温室气体的农业新技术的核心，本文介绍的就是利用这种新技术处理温室气体的方法，故B项正确。

2.细节理解题。根据第二段内容可知，当艾罗科树生长在干燥、酸性的土壤中并经过天然真菌和其他细菌的组合处理后，它不仅生长良好，还会在根部周围的土壤中产生矿物质石灰石，由此可知，在某种特殊的土壤中，艾罗科树能够和微生物相处得很好，故D项正确。

3.词义猜测题。根据画线前的“In addition to storing carbon in the trees’ leaves and in the form of limestone, the mineral in the soil makes”可知，除了在树叶和石灰石中储存碳外，土壤中的矿物质使土壤更适合农业生产，由此可知it指代的就是前面提到的“土壤”，故C项正确。

4.推理判断题。根据倒数第二段中的“The project examined several microbiological methods of locking CO2 as limestone, and the Iroko-bacteria way showed best results.”可知，该项目研究了多种将二氧化碳锁定为石灰石的微生物方法，其中艾罗科树和微生物的方法效果最好，再结合最后一段内容可知，研究人员倾向于使用自然力量来解决温室气体的问题，故C项正确。

5.细节理解题。根据最后一段中的“By taking advantage of this natural limestone-producing process, we have a low-tech, safe, readily employed and easily operating way to lock carbon out of the atmosphere, while improving farming conditions in tropical countries.”可知，通过利用这种天然的石灰石生产过程，我们有了一种低技术、安全、易于操作的方法锁定大气中的碳，同时改善热带国家的农业条件，由此可知，这种方法能够用于改善耕地，故A项正确。