Being highly connected to a strong social network has its benefits. Now a new study is showing the same goes for trees, thanks to their underground neighbors. The study is the first to show that the growth of adult trees is linked to their participation in fungal (真菌) networks living in the forest soil. Though past research has focused on young trees, these findings give new insight into the importance of fungal networks to older trees, which are more environmentally beneficial for functions like capturing carbon.
“Large trees make up the main part of the forest, so they drive what the forest is doing, ” said researcher Joseph Birch, who led the study. When they live in the forest soil, fungal net- works act as a sort of highway, allowing water, nutrients and compounds to flow back and forth among the trees. The network also helps nutrients flow to resource-limited trees like family units that support one another in times of stress.
Cores (核心) taken from 350 Douglas firs (花旗松) showed that annual tree ring growth was related to the extent of fungal connections a tree had with other trees. They had much higher growth than those that had only a few connections. The research also showed that trees with more connections to many unique fungi had much greater growth than those with only one or two connections. “If you have this network that is helping trees grow faster, that helps capture more carbon year after year. These networks may help trees grow more steadily even as conditions become more stressful, and could even help protect them against death. ” said Birch.
Birch hopes his findings lead to further studies in different kinds of forests in other geographical areas, because it’s likely that the connections among trees change from year to year. He said, “Knowing whether fungal networks are operating the same way in other tree species could inform how we reforest areas after harvesting them, and inform how we plant trees to preserve these networks. ”
1. In what way do the new findings differ from the previous ones?| A．They demonstrate a new way to capture carbon. |
| B．They confirm the benefits of fungal networks. |
| C．They clarify misunderstandings of fungal networks. |
| D．They reveal the value of fungal networks to adult trees. |
| A．By fighting against diseases. |
| B．By bettering forest soil conditions. |
| C．By acting as the center of family units. |
| D．By maintaining the balance of resources. |
| A．Tree rings. | B．Cores from firs. |
| C．Douglas firs. | D．Fungal networks. |
| A．The fungal networks support one another in times of stress. |
| B．The fungal networks enable us to know more about reforestation. |
| C．The findings can apply to different kinds of forests in other geographical areas. |
| D．The networks will help trees grow steadily if conditions become more stressful. |
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Most workers attend so-called happy hours to bond with colleagues, although 15 percent go to hear the latest office gossip and 13 percent go because they feel necessary, said the survey conducted for CareerBuilder. com, an online job site. As to what happens when the after-work drinks flow, 16 percent reported bad-mouthing a colleague, 10 percent shared a secret about a colleague and 8 percent said they drank too much and acted unprofessionally. Five percent said they had shared a secret about the company, and 4 percent confessed to singing karaoke. While 21 percent of those who attended said happy hours were good for networking, 85 percent said attending had not helped them get closer to someone higher up or get a better position. An equal number of men and women said they attended happy hours with co-workers, with younger workers aged 25 to 34 most likely and workers over 55 least likely to attend. Overall, 21 percent of workers attend happy hours with co-workers and; of those nearly a quarter go at least once a month.
The survey was conducted online by Harris Interactive on behalf of CareerBuilder. com among 6,987 full-time employees between February 11 and March 13. Harris Interactive said the results had a sampling error of plus or minus 1.2 percentage points.
1. Harris Interactive made the survey to find out ________.
| A．how U.S. workers spend their after-work time |
| B．what U.S. workers do at after-work drinks |
| C．the relationships between U.S. workers |
| D．who are most likely to attend after-work drinks |
| A．4 percent | B．8 percent | C．16 percent | D．10 percent |
| A．benefited them a lot | B．could provide information |
| C．only made them relaxed | D．was of no help to them |
| A．workers over 55 don’t like to attend happy hours at all |
| B．about 75% of workers go more than once a month |
| C．10.5% of male workers attend happy hours with co-workers |
| D．about 700 workers surveyed shared a secret about a co-worker |
| A．all the workers oppose after-work drinks |
| B．the workers may change their attitudes towards after-work drinks |
| C．all the workers support after-work drinks |
| D．all the workers are suggested going to attend after-work drinks |
【推荐2】Ancient China produced many types of beautiful works of art. Among them, calligraphy, poetry and painting are the most famous. Often they would be put together in art.These became important starting with the Song Dynasty.
Calligraphy is the art of handwriting. In the old times the Chinese considered writing as an important form of art. Calligraphers would practice for years to learn to write perfectly, but with style. Each of the over 40,000 characters needed to be written correctly. And each stroke (笔画) in a character had to be written in a certain order.
Poetry is also an important form of art. Great poets were famous all over the country, and all educated people were expected to write poetry. During the Tang Dynasty poetry was so important that writing poetry was part of the examinations to become a civil servant (文官) and work for the government.
Chinese painting is often connected with calligraphy. It is one of the oldest artistic traditions in the world. The most traditional way of Chinese painting is known as “national painting” or “native painting” which is quite different from Western painting. People can draw mountains, buildings, birds, trees and water.
1. Calligraphers needed to write over ______ characters correctly in the old times.| A．10,000 | B．20,000 |
| C．30,000 | D．40,000 |
| A．Painting. | B．Calligraphy. |
| C．Writing poetry. | D．Playing music. |
| A．Chinese art. | B．Chinese examinations. |
| C．Chinese history. | D．Chinese dynasties. |
【推荐3】Earthquakes are something that people fear. There are some places that have few or no earthquakes. Most places in the world, however, have them regularly (有规律的). Countries that have a lot of earthquakes are usually quite mountainous (多山的).
The most talked about earthquake in the United States was in San Francisco in 1906. Over 700 people died in it. The strongest one in North America was in 1964. It happened in Alaska.
Strong earthquakes are not always the ones that kill the most people. In 1755, one of the strongest earthquakes ever recorded was felt in Portugal. Around 2,000 people died.
In 1923, a very strong earthquake hit the Tokyo, Yokohama area of Japan. A hundred and forty thousand people died. Most of them died in fires which followed the earthquake.
One of the worst earthquakes ever was in China in 1976. It killed a large number of people. The worst earthquake ever reported was also in China, in which 400,000 people were killed or injured. This earthquake happened in 1556.
Earthquakes worry people a lot. The reason is that we often do not know when they are coming. People can not prepare for it.
1. Earthquakes happen __________ .| A．in all the places in the world |
| B．only in the countries that have a lot of mountains |
| C．regularly in most places in the world |
| D．only in a few places along the coast |
| A．500. | B．140,000. | C．400,000. | D．2,000. |
| A．1964; Alaska. | B．1556; China. | C．1923; Japan. | D．1976; China. |
【推荐1】Madagascar, the world’s second-largest island country located off Africa’s eastern coast, is an island of diverse ecosystems and a biodiversity hotspot. The country has unique wildlife, with 90% of its plants and animals found nowhere else. Madagascar’s wildlife creates some of the country’s most beautiful scenery and popular spots. One of its conspicuous landscapes, attracting tourists from almost all corners of the Earth, is the Avenue of the Baobabs in the Menabe region. This avenue is made up of numerous baobab trees along the dirt road linking Belon’i Tsiribihina and Morondava, creating a unique and beautiful setting.
Baobab trees are common throughout Madagascar. Of the Earth’s eight species, six are native to the country. Some of the baobabs in the country are about 2, 800 years old, with trunks rising to 150 feet. The avenue is a row of about 25 baobabs stretching about 260 meters. Other baobab trees are also found in the nearby pastures (牧草地). This road is one of Madagascar’s most visited places. It is also the most accessible place to see some of Africa’s oldest baobabs. These trees were once part of a forest that was made up of other plants. However, massive deforestation cleared the area of most trees, leaving the baobabs to grow alone.
The baobab trees along the road and the other species growing in the nearby areas are always under constant threat from the increasing population. The trees also face threats from polluted water from the nearby fields, forest fires, and bushfires. Despite being a popular tourist attraction, the Avenue of the Baobabs has no admission fee or visitor center and generates little money for local communities.
Thankfully, non-governmental organizations in partnership with the government have noticed the area and developed activities to protect the avenue. The Ministry of Environment, Ecology, and Forests declared it a temporary protected area in July 2007. In July 2015, the site was declared a national monument (国家保护区), the first in Madagascar. The government and local communities hope the trees can survive for additional 800 years.
1. What does the underlined word “conspicuous” in the first paragraph mean?| A．New. | B．Cultural. | C．Striking. | D．Changing. |
| A．It is a big forest. | B．It has eight baobab species. |
| C．It consists of many different plants. | D．It has Africa’s oldest baobabs. |
| A．The risk to local baobab trees. |
| B．Natural disasters in Madagascar. |
| C．Poor living conditions in Madagascar. |
| D．The quality customer service of the avenue. |
| A．Curiosity. | B．Caution. | C．Hopefulness. | D．Sympathy. |
【推荐2】In the Hollywood movie The Martian, actor Matt Damon plays an astronaut who grows food on Mars (火星) to survive alone on the red planet.
After seeing the movie, Washington State University physicist Michael Allen and University of Idaho food scientist Helen Joyner decided to carry out a case study helping students figure out how to farm on Mars. In the case study, students had to imagine they were mining on Mars and decide how to feed themselves there before starting on the journey. They got advice from Allen and Joyner on how to select crops and take the challenges of growing crops over long periods on Mars. Students used a scoring system to select three foods to plant on Mars.
Allen found the results impressive: among 30 students, “no two people have ever gotten the same answer”, he said.
Human travelers to Mars will likely have to make use of resources on the planet rather than take everything they need with them on a spaceship. This means farming their own food on another planet, one that has a very different ecosystem (生态系统) from Earth’s.
One challenge for those who would like to live on Mars is the fact that there can be no farming tools. Like real astronauts, students taking part in the study cannot take farming tools with them. As Joyner put it to his student astronauts, “You are starting with nothing.” Besides, students also have to deal with a very limited choice of diet. “If you had to eat a single food for the rest of your life, could you do it?” Joyner asked.
But Allen believes the case study is about more than farming and eating on the Red Planet. “I’m not teaching about growing food on Mars,” Allen said, “I’m teaching about living with choices. I’m teaching about problem solving.”
1. What made Michael Allen and Helen Joyner carry out the case study?| A．A trip. | B．A book. | C．A movie. | D．A lecture. |
| A．start with everything | B．try different tools |
| C．watch the movie | D．select three foods |
| A．They have a limited choice of diet. | B．They have a lot of farming tools. |
| C．They have to take part in the study. | D．They have to select crops on Mars. |
| A．how to look for foods on Mars | B．to know more about Earth |
| C．how to solve problems | D．to learn about gardening |
| A．a research on how to farm on Mars | B．a Hollywood movie The Martian |
| C．how to survive alone on Earth | D．how to design a scoring system |
【推荐3】The forests of today will not be the forests of tomorrow.
Rising temperatures, deforestation (森林砍伐), development and climate-caused disasters are changing the very form of Earth’s forests, new research published in the journal Science finds.
Older, bigger trees are being lost at an amazing rate, making the planet’s forests shorter and younger in general.
The shift is being driven at different rates by different causes in different places, the study’s authors say, but the consequences will be global.
Old growth forests absorb and store massive amounts of climate-warming carbon dioxide (二氧化碳). They provide home for rare and critically endangered species and make the biology diverse. And they’re disappearing fast.
Warming temperatures, wildfires, and insect outbreaks were among the many causes of the decline, says Nate McDowell, the study’s lead author.
Just in the past year, the world has watched as massive wildfires across Siberia, the Amazon and Australia. Deforestation in Southeast Asia and Brazil continue rapidly.
Human-driven climate change is also making it difficult for many forests to fully recover from the type of natural behaviors — wind events, flooding or fire — that would normally occur.
The researchers did find evidence that increased carbon dioxide in the atmosphere could increase tree growth in some places, but not to an extent where it would outweigh the harm being done by increased temperatures. The most important trend was one of loss.
“I would recommend that people try to visit places with big trees now, while they can, with their kids,” McDowell says. “Because there’s some significant threat, that might not be possible sometime in the future.”
1. What does the author mean by saying “The forests of today will not be the forests of tomorrow”?| A．Tree species in forests will be changed as governments plan. |
| B．The climate of tomorrow will be different from that of toady. |
| C．The form of forests will be changed due to various reasons. |
| D．Animals in the forests will die away at an amazing rate. |
| A．People are planting a great deal of trees. |
| B．People are involved in protecting forests. |
| C．The growth of new trees is threatening that of big ones. |
| D．The number of older and bigger trees is dropping greatly. |
| A．They are harmful to the growth of younger trees. |
| B．They are home to many rare and endangered trees. |
| C．They rely largely upon weather conditions. |
| D．They serve as the habitats for most birds. |
| A．Because they would be impressed by their beauty. |
| B．Because they would keep away from busy life temporarily. |
| C．Because there might be no big trees at all in the future. |
| D．Because warmer climate might destroy all trees globally. |
