The damage brought by wildfires reaches everything that lives in or near a burning field or forest, including microbes (微生物). A better understanding of how microbial communities change and grow after a fire could help researchers predict how bacteria and fungi will deal with major environmental changes.
A study published this week in mSystems suggests that dispersal (传播)—through air or rain, for example—plays a major role in microbial succession (更迭) after a big fire. Researchers at the University of California, Irvine, spent a year tracking how microbial communities returned to the leaf litter in a burned field. They found that the emerging microbial communities in the soil surface changed with the seasons and the reappearance of plants, and that the gathering of those communities was largely driven by dispersal.
“We know with climate change and human activity we’re disturbing our ecosystems more and more,” said Kristin Barbour, lead author on the new study and a Ph. D. student at the University of California, Irvine. “Microbes, especially those in the surface soil, perform a number of really key ecosystem processes, like carbon and nitrogen cycling.” Bacteria and fungi, she said, break down the dead and decaying (腐烂的) plant matter on the floor of a field or forest.
Barbour originally set out to study microbial dispersal in the context of droughts, but her plans changed after an unexpected wildfire burned a field site at Loma Ridge, near Irvine. What seemed like a trouble became an opening. “We wanted to take advantage of this disturbance, especially since wildfire is becoming more frequent in many parts of the world,” Barbour said.
1. Which of the following depends on microbes?| A．Climate change. | B．Wildfire control. | C．Ecosystem cycling. | D．Pollution prevention. |
| A．Microbes can’t survive in extreme droughts. |
| B．Her work is often interrupted by changing weather. |
| C．She couldn’t get the government’s support. |
| D．A wildfire accidentally broke out in a certain place. |
| A．Opportunity. | B．Dream. | C．Thought. | D．Solution. |
| A．Wildfire is becoming more frequent. | B．How microbes return after a wildfire. |
| C．Wildfires do much damage to microbes. | D．Microbes play a key role in ecosystem. |
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【推荐1】For years,Hagelin has studied what role scents（气味）play in wild birds’ behavior.In 2010,Hagelin heard Jan Straley,a marine biologist,talk about the behavior of whales.Straley mentioned that whales often leap into the air,but nobody knew why.
The mystery interested Hagelin.So Hagelin asked Straley whether they might leap to smell the air—maybe to locate food or look for danger.Straley replied that it was an interesting idea but there wasn't much evidence that whales have a sense of smell.To investigate the idea further,the two scientists teamed up.
In the summer of 2011,they set up a post on the coast of southern Alaska.The researchers spent hours monitoring the direction of the whales and of the wind.The whales headed into the wind half of the time.This didn't prove that whales leap to smell,but it suggested that it is possible.
Meanwhile,other researchers in Alaska were studying a region of the brain called the olfactory bulb（嗅觉球）in whales.Olfaction means the ability to smell.Humans also process smells in the olfactory bulb.
In identifying a scent,you might think the nose does all of the work.However,the major role of a nose is to draw chemicals on the air and pass them across sensing cells.As chemicals come into contact,they give signals that travel directly to the bulb and then in the brain for further interpretation.
The researchers discovered that the bulb in a whale was more complex than the one in a human.In whales,this smell-processing center takes up a share of the brain six times larger than it does in humans.
The brain research suggested that whales probably can smell just as well as people—and possibly better than humans can.It is supposed that a good sense of smell could help them find food more easily.
However,Hagelin is not sure of that.Now he is planning a new study that will examine whether whales do use the sense of smell to find food.
1. Hagelin and Straley set up a post with the purpose of finding______.| A．how whales look for food in groups |
| B．whether whales can get out of danger |
| C．how whales head into the wind |
| D．whether whales leap to smell the air |
| A．is smaller than the one in a human |
| B．draws chemicals spreading in the air |
| C．is more complex than the one in a human |
| D．processes smells better than the one in a human |
| A．hasn't got any evidence that whales have a sense of smell so far |
| B．doesn't know whether whales hunt their food in groups |
| C．isn't sure that the sense of smell can help whales find food |
| D．isn't sure whether humans can smell as well as whales |
| A．Education. | B．Science. |
| C．Culture. | D．Agriculture. |
【推荐2】Can dogs and cats live in perfect harmony in the same home? People who are thinking about adopting a dog as a friend for their cats are worried that they will fight. A recent research has found a new recipe of success. According to the study, if the cat is adopted before the dog, and if they are introduced when still young (less than 6 months for cats, a year for dogs), it is highly probable that the two pets will get along swimmingly. Two-thirds of the homes interviewed reported a positive relationship between their cat and dog.
However, it wasn’t all sweetness and light. There was a reported coldness between the cat and dog in 25% of the homes, while aggression and fighting were observed in 10% of the homes. One reason for this is probably that some of their body signals were just opposite. For example, when a cat turns its head away it signals aggression, while a dog doing the same signals submission (服从).
In homes with cats and dogs living peacefully, researchers observed a surprising behavior. They are learning how to talk each other’s language. It is a surprise that cats can learn how to talk “dog”, and dogs can learn how to talk “cat”.
What’s interesting is that both cats and dogs have appeared to develop their intelligence.
They can learn how to read each other’s body signals, suggesting that the two may have more in common than we previously suspected. Once familiar with each other’s presence and body language, cats and dogs can play together, greet each other nose to nose, and enjoy sleeping together on the sofa. They can easily share the same water bowl and in some cases groom (梳理) each other.
The significance of the research on cats and dogs may go beyond pets-to people who don’t get along, including neighbors, colleagues at work, and even world superpowers. If cats and dogs can learn to get along, surely people have a good chance.
1. Which below is closest in meaning to the word “swimmingly” in Paragraph 1?| A．Smoothly. | B．Briefly. | C．Quickly. | D．Early. |
| A．They are introduced at an early age. |
| B．They are cold to each other. |
| C．They misunderstood each other’s signals. |
| D．They stared at each other. |
| A．are less different than we thought |
| B．have common interests |
| C．are less intelligent than we expected |
| D．have a common body language |
| A．To live in peace with animals. |
| B．To live in harmony. |
| C．To know more about animals. |
| D．To learn body signals. |
【推荐3】Forgiving (宽恕) someone who has hurt you or let you down is never an easy thing. Several new studies, however, say that it could have a lot of health benefits (好处). When you think of forgiveness, you probably don’t think of it as being a health or medical problem. Studies from Stanford University, on the other hand, show that something like anger can change your well-being (健康).
When cartoon book characters like the Incredible Hulk get angry, they change colours and often gain special power. In the real world, anger is less clear and may be more dangerous. That’s why Professor Fred Luskin, founder of the Stanford Forgiveness Project and writer of Forgive for Good, says holding on to anger and hatred can harm your physical and mental health. Two new studies seem to show the same idea.
The studies find that people who are able to forgive feel less stress, less back pain, and less sadness or hopelessness. They also have fewer headaches, lower blood pressure, and fewer problems on sleeping.
So it doesn’t matter if your anger is caused by the traffic or other things. Learning to let it go is important. Techniques such as deep breath or thought can help. Or just ask yourself if it’s worth hurting yourself by staying angry with someone else.
Forgiveness does not mean that you simply accept what happened and say it’s OK. Instead, it’s a way of making peace with yourself about what happened in the past.
1. The writer of the passage tries to make his point clear by .| A．mentioning some studies | B．sharing his own experience |
| C．raising some questions | D．mentioning some health problems |
| A．show how to control oneself |
| B．introduce a famous professor |
| C．support his point on anger and hatred |
| D．tell the readers cartoon characters are powerful when they get angry |
| A．It’s not easy to know if you are angry. |
| B．People who are able to forgive feel less tired. |
| C．It’s hard to forgive someone who hurts you. |
| D．You can let your anger go by breathing deeply. |
| A．Forgiving Others Is Hard | B．Anger Is Bad for Health |
| C．Learning to Forgive Is Important | D．Forgiveness Is Good for Health |
【推荐1】The sporty all-electric car from the Netherlands resembles a BMW coupe (双门轿车), but is unique: It captures more carbon than it emits. Called ZEM, for zero emission mobility, the two-seater houses a Cleantron lithium-ion battery pack, and most of its parts are 3D-printed from recycled plastic.
“Our end goal is to create a more sustainable future,” said Jens Lahaije, finance manager for TU/ecomotive, the Eindhoven University of Technology student team that created the car. “The target is to minimize carbon dioxide emitted during the car’s full lifespan, from manufacturing to recycling,” he added.
Direct Air Capture(DAC) technology captures carbon dioxide by pulling in atmospheric air, and then through a series of chemical reactions, extracts the carbon dioxide(CO2) from it while returning the rest of the air to the environment. The team has made use of this innovative technology and implemented (执行) this in the car. The idea is very simple: while driving, air will move through the self-designed filters and the CO2 will be captured and stored.
ZEM uses two filters that can capture up to 2 kilograms(4.41 lb)of CO2 over 20,000 miles of driving, the Eindhoven team estimated. They imagine a future when filters can be emptied at charging stations.
Nikki Okkels, external relations manager at TU/ecomotive: “We want to tickle (使发痒) the industry by showing what is already possible. If 35 students can design, develop and build an almost carbon-neutral car in a year, then there are also opportunities and possibilities for the industry. We’re not finished developing yet either, and we want to take some big steps in the coming years. We warmly invite car manufacturers to come and take a look.”
1. What do we know about the sporty all-electric car?| A．It is developed by BMW manufacturer. |
| B．It can totally transform CO2 into oxygen. |
| C．Its body is completely made from recycled plastics. |
| D．It contains a Cleantron lithium-ion battery pack. |
| A．To minimize the expense of the car. | B．To reduce CO2 emission greatly. |
| C．To enlarge the lifespan of the car. | D．To sustainably recycle more cars. |
| A．Air will be stored in the two filters of the car. |
| B．CO2 is isolated from air through chemical reactions. |
| C．It has been widely applied in automobile making industry. |
| D．The filters can be emptied in the process of driving the car. |
| A．Promising. | B．Problematic. | C．Profitable. | D．Widely-used. |
【推荐2】Tonya, Elsa and Mark are students at SAR Senior High School in New York City. It's a school with regular academic (学术的) classes, but it also gives special attention to the performing arts. Tonya likes dancing. Elsa wants to be an artist and Mark is a singer.
The students are all 15, and they're in the 10th grade. They study subjects like English, maths, social studies, science and PE. They also choose a foreign language: French, Italian, Spanish or Japanese. Students have many academic classes, but during the school day they also take classes in the arts, like theater, art, dance and music.
There are even more activities for SAR students after school. There are more than 40 clubs for students. For example, there's a movie club, a music club and an environmental club. “We have so many choices to select," says Tonya. “I like taking photos. It's also a great way to meet people with common interests."
Students at SAR can also do many sports. For example, they can play basketball, tennis, volleyball and soccer. Students practice after school. They compete against other high schools. Mark says, “At school, I study by myself. I'm a singer, and I do that alone, too. That's why I like playing on the basketball team. We work together and compete against other teams."
SAR offers various great classes, clubs and sports for students. Students at SAR get a good education and they also develop their own interests. Many SAR students become dancers, singers and actors!
1. What do we know about SAR Senior High School?| A．Students take art classes at night. |
| B．Students have few subjects to choose from. |
| C．It places great importance on arts. |
| D．It aims to develop students’ language skills. |
| A．The photography club. | B．The music club. |
| C．The movie club. | D．The environment club. |
| A．It helps him make more friends. | B．It makes him try his best. |
| C．He hopes to build up his health. | D．He likes teamwork. |
| A．Education at SAR. | B．Top Students at SAR. |
| C．School Life at SAR. | D．SAR’s after-school activities. |
【推荐3】“We are running out of space and the only places to go to are other worlds… Spreading out may be the only thing that saves us from ourselves. I’m convinced that humans need to leave Earth.” These are the words of the famous scientist Stephen Hawking, spoken at a science festival in Norway in 2017, a year before his death.
Hawking was not alone in this view. Many experts feel that the only way for humanity to last far into the future is to colonize(移民于) other planets. That way, if a terrible disease, nuclear war or some other disaster strikes Earth, civilization as we know it would still have a chance. Mars is one of the most attractive destinations. NASA, the United Arab Emirates, the private company SpaceX, and the organization Mars One all have plans to send humans there. “Either we spread Earth to other planets, or we risk going extinct,” SpaceX founder Elon Musk said at a conference in 2013.
But not everyone agrees that colonizing Mars or any other planet is such a great plan. The most common argument against going is that it’s just too expensive or dangerous. It will take huge amounts of money and other resources just to get people there, let alone set up a place for them to live. It’s not even clear if humans could survive on Mars. One of the biggest dangers there is deadly radiation that ruins the planet.
Maybe all the time and money people would pour into a Mars mission would be better spent on more urgent projects here on Earth, like dealing with poverty or climate change. Some experts argue that handling a problem like an asteroid(小行星) strike or disease outbreak while staying here on Earth would be much easier and less expensive than surviving on a new planet.
In addition, moving to a new planet could harm or destroy anything that already lives there. Mars seems uninhabited, but it could possibly host micro-organism like. Human visitors may destroy this life or permanently change or damage the Martian environment. Some feel that’s too much of a risk to take.
1. Why did the author mention NASA, the United Arab Emirates, SpaceX and Mars One?| A．To stress the risk of dying out on Earth. |
| B．To provide evidence for Hawking’s theory. |
| C．To show growing intention of moving to Mars. |
| D．To explain the advanced technology in astronomy. |
| A．It is costly and risky to colonize Mars. |
| B．Civilization is difficult to maintain on Earth. |
| C．Poverty is the most urgent problem to handle. |
| D．All the time and money should be spent on Earth. |
| A．not steady to keep. | B．not fit to live on. |
| C．not easy to approach. | D．not safe to set foot on. |
| A．Leaving Earth to Other Planets |
| B．Should We Colonize Mars? |
| C．New Home on New Planet |
| D．A Mar Mission Is on The Way |
