Most gardeners know that earthworms (蚯蚓) help keep soils healthy. Now scientists have assessed just how important their underground activities are to global food production — and how to protect them.
In research published this September, scientists found that earthworms may contribute to more than six percent of global grain production every year, because of their crucial role in soil ecosystems.
Worms help to break down dead plant material, releasing nutrients plants need to grow, and their tunneling (挖隧道) helps plant root growth. Evidence suggests they also help plants protect themselves against common soil-related diseases by stimulating their defenses.
“Their contribution may even be larger,” said Steven Fonte, an associate professor at Colorado State University in the United States who co-authored the research. “This is because earthworm populations are likely underestimated in many places, especially in the tropical areas, due to a lack of research and funding in the global south.” he explained.
The authors said their findings represent one of the first attempts to quantify the contribution of a beneficial soil organism to global agricultural production. They found that earthworm contribution is especially high in the global south, contributing about 10 percent of total grain production in sub-Saharan Africa and roughly eight percent in Latin America and the Caribbean. They owed this to soils there generally having higher acid and clay content and being less exposed to fertilizer (肥料), increasing the role earthworms play in plant growth.
Scientists figured that earthworms are threatened by today’s intensive and chemical-heavy agricultural techniques. Agricultural and environmental policies should support earthworm populations and soil biodiversity to promote more sustainable development. Measures could include reducing the use of land for growing crops, cutting the use of poisonous chemical substances, and increasing the application of worm food sources. “Soils are estimated to contain approximately half of all biodiversity on the planet and are incredibly important for biodiversity conservation efforts,” Fonte said.
1. How do earthworms benefit the soil ecosystems?| A．By increasing the number of plant roots. | B．By reducing fertilizer’s effects. |
| C．By helping plants against certain diseases. | D．By breaking down nutrients. |
| A．The good soil quality. | B．The advanced agriculture. |
| C．The supportive policy. | D．The earthworm-friendly climate. |
| A．Expanding the farming land. | B．Providing healthy food for them. |
| C．Banning intensive agriculture. | D．Using fewer harmful chemicals. |
| A．Earthworms: An Assistant to Soil Health |
| B．Earthworms: Their Threats and Conservation |
| C．Earthworms: The Decisive Factor in Biodiversity |
| D．Earthworms: A Contributor to World Food Production |
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【推荐1】The sharp fin (鳍). The rows upon rows of sharp teeth. The large black eyes. The sharks you see on television in Jaws or Discovery’s ”Shark Week“ are not the friendliest looking creatures. They aren’t exactly an animal you want to find near you while swimming in the ocean. Despite their portrayals (刻画) in movies and popular culture, sharks are complicated, misunderstood creatures that are weaker than they appear.
One very common misunderstanding about sharks is their desire to hunt humans. Actually when sharks attack humans, it is because they mistake a human for their normal prey (猎物),seals or dolphins. They don’t seek out humans on purpose. Statistically, you are more likely to be struck by lightning than be bitten by a shark.
Sharks are very important to the ocean as they are at the top of the food chain. Some sharks even control the balance of an ecosystem through fear alone. Tiger sharks in Australia help protect seagrass meadows from turtles. Turtles eat the seagrass and without the sharks, will destroy these meadows. When tiger sharks are present though, the turtles are scared away, holding back their appetite for seagrass and protecting its growth.
Though sharks have a reputation for being very scary to humans, the sad truth is that they should be scared of humans. The number of sharks in the ocean is steadily dropping. There are a few reasons for this. For one, they mature quite slowly, over several years, and produce relatively few young. For another, overfishing of sharks is happening because more and more people want their fins. About 100 million sharks are killed every year according to National Geographic. Shark fin is a way for people to show off their wealth. Shark fins are also believed to have medicinal benefits, though there is no evidence or proof that they actually do.
1. What do most people think about sharks?| A．They are ugly. |
| B．They are important |
| C．They are violent. |
| D．They are complicated. |
| A．Deadly | B．rare | C．unavoidable | D．unpredictable |
| A．Humans keep sharks to show off. |
| B．Humans kill sharks in large quantities. |
| C．Humans catch sharks for medical research. |
| D．Humans are greater in number than sharks |
| A．SOS: Save Our Sharks! |
| B．Sharks: King of the Ocean |
| C．Shark Fins: An Ecological Crisis |
| D．Sharks: Killers or Misunderstood? |
【推荐2】Search and rescue teams are often accompanied by man’s best friend. A dog’s superior sense of smell can be of importance to finding survivors buried(埋) under fallen buildings. But now a new animal is being trained to assist search and rescue teams after an earthquake hits, and it’s the rat.
These rescue rats are being trained by Dr. Donna Kean, a researcher from Glasgow, Scotland who has been working with rats for years. Kean explained why she and her colleagues at the nonprofit APOPO train rats instead of dogs. “The rats have a comparable sense of smell, and they’re just as trainable as dogs,” she said.
“Their size is useful because they will be able to move through different environments that dogs just wouldn’t be able to.”
At the moment, the rats are wearing homemade prototype backpacks (背包) that contain microphones, video equipment, and location trackers, and then scientists are sending these rats into mock debris (模拟的废墟). Rats would be able to get into small spaces to get to victims (受害者) buried in the ruins. “We have not been in a real situation yet, we have got a mock debris site. When we track the backpack, we will be able to hear from where the rat is inside the debris,” Kean said. “We have the potential to speak to victims through the rat.”
Researchers train them on a basic series of behaviour. Training starts off in a really basic environment: a small and empty room. Then they gradually expand and increase the complexity(复杂性) in order to make it like real life.
They can start adding in debris and making the training area look more like an actual collapsed building site.
The training just started, and researchers still have to run training trials(实验) outside the research environment.
They are working with a search and rescue group called GEA, who are based in Turkey, a country with frequent earthquakes and hoping that by next year they’ll be able to take the rats to Turkey for trials.
1. What advantage do rats have over dogs in the rescue work?| A．They are easier to train. | B．They have a better sense of smell. |
| C．They are more flexible with a smaller size. | D．They adapt to new environments more quickly. |
| A．impressive. | B．suitable. | C．unique. | D．similar. |
| A．The process of training the rats. | B．The difficulty of conducting experiments. |
| C．The rats’ behaviour in real collapsed sites. | D．The importance of the research environment. |
| A．Use rats for rescue work in large numbers. | B．Send rats to Turkey for field experiments. |
| C．Carry out further study on disaster prevention. | D．Develop the tracking technology to assist GEA. |
【推荐3】Many of us think of sharks as powerful, mysterious, and lonely as they move through the deep. And nowonder the fish have long been portrayed in popular media as lone predators, appearing out of nowhere to attack. But that image has come under inspection in recent years, as shark researchers around the world have discovered the fish gathering in large numbers and interacting with others of their own species in ways that are obviously friendly.
Yannis Papastamatiou, a marine scientist at Florida International University, and his team used acoustic transmitters to record the interactions over four years of about 40 reef sharks around Hawaii. Their study found that reef sharks return to the same communities year after year, forming clear preferences for sharks with some friendships that endured throughout the study. In his 2016 study, he found that individual sharks tagged with recording devices had thousands of interactions with their peers, with some pairs spending up to four straight days together. The study also found certain sharks were unmistakably companions. “These weren’t random associations,” he says.
Finding out why sharks socialize — and how much of their behavior is cooperative — is a challenge, but there are some clues, such as food availability and warmer waters. Great white sharks, are showing up in record numbers along southern California beaches as the population has doubled since 1994. While great white sharks typically maintain distances of about 30 feet from each other and don’t seem too close, they are clearly drawn together by a preference for the area. In some cases, there may not be an obvious purpose for shark’s friendship. At the Bimini Shark Lab, Smukall and his colleagues found that young lemon sharks sought out companionship of other sharks for no clear reason. There’s growing evidence that lemon sharks have their own personalities, which may influence whether they spend time with other sharks, he adds.
More would be known about the intimate lives of sharks if the field weren’t so new, due in part to a lack of funding and sharks’ negative reputation. “We’ve only had about 20 years to really start studying sharks,” says Smukall.
1. Why do the reef sharks return to the same groups every year?| A．To move to other places together. | B．To find a better place to lay eggs. |
| C．To change the food chain of the sea. | D．To search for the company of other fish. |
| A．Global Warming. | B．Preference for an area. |
| C．Sharks’ personalities. | D．Food availability. |
| A．Sharks usually spend four days with their peers. |
| B．The relationship between some sharks is steady. |
| C．All the sharks were attached to recording devices. |
| D．Sharks have thousands of interactions every day. |
| A．Sharks always have a bad reputation. |
| B．Scientist will begin studying sharks in 20 years. |
| C．There will be a long way to go before knowing sharks completely. |
| D．It is unnecessary to put money into the research of the sharks. |
【推荐1】Since the prehistoric times, man has had an urge to satisfy his needs. Be it hunger, shelter or search for mate, he has always used the circumstances to the best of his advantages. Probably this might be the reason why we human are the most developed of all living species on the earth and probably also in the universe. As we climbed the steps of evolution, we somehow left behind common sense and logical thinking. We forgot that we have stopped thinking ahead of times.
If you are hungry, what do you do? Grab a piece of your favorite meal and stay quiet after that? Just like your stomach, your mind is also hungry, but it never lets you know, because you keep it busy thinking about your appearance, favorite star and many such ridiculous things. So it silently began to give way to your needs and never let itself grow. When mind loses its freedom to grow, creativity gets a full stop.
Hunger of the mind can be actually satisfied through extensive reading. Now why reading but not watching TV. Because reading has been the most educative tool used by us right from the childhood. Just like how to develop other aspects of our life, we have to take help of our reading. You have numerous books in this world which can answer all your “how to” questions.
Once you read a book, you just don’t run your eyes through the lines, but your mind decodes it and explains it to you. The interesting part of the book is stored in your mind as a seed. Now these seeds are unknowingly used by you in the future to develop new ideas. The same seed, if used many times, can help you link a lot of things which you would have never thought of in your wildest dreams. This is nothing but creativity. More the number of books you read, your mind will open up like never before. Also this improves oral skills to a large extent and makes a significant contribution to your vocabulary. Within no time you start speaking English or any language fluently with your friends or other people. And you never seem to run out of the right words at the right time.
1. What helps man become the most advanced species in the world?| A．Searching for food and shelter. | B．Taking good care of the young. |
| C．Making the best of the surroundings. | D．Adopting a great deal of logical thinking. |
| A．They are occupied with absurd thoughts. | B．They are too engaged with the daily routine. |
| C．They lose the freedom to grow. | D．They think little of mental health. |
| A．By enlarging their vocabulary. | B．By answering “how to” questions. |
| C．By explaining the content of a book. | D．By assisting in the formation of new ideas. |
| A．Reading helps realize one’s dream. | B．Reading meets man’s hunger in mind. |
| C．Reading is a best habit for teenagers. | D．Reading can replace food for human. |
【推荐2】A team of early childhood researchers examined how neighborhood opportunity — the socioeconomic, educational, health, and environmental conditions relevant to child health and development — is associated with infant (婴儿) brain activity and cognitive development.
The researchers found that infants in neighborhoods with more opportunities have greater brain function at six months of age. In areas with better educational opportunities, these brain differences are also related to better cognition at 12 months old.
The researchers collected their data from 65 infants in community pediatric (小儿科的) practices in the Boston and Los Angeles areas. The team examined whether associations between neighborhood opportunity and children’s cognitive development at 12 months of age could be explained by differences in brain activity at 6 months of age, measured by electroencephalography (脑电图学) (EEG). Cognitive development was measured using the Mullen Scales of Early Learning(MSEL), a standardized play-based developmental assessment.
The researchers found that higher levels of neighborhood opportunity are associated with greater absolute EEG power in mid-to high-frequency bands in six months old infants. These EEG measurements are related to better language and cognitive scores later in childhood, suggesting a neuroprotective role of living in higher opportunity neighborhoods early in life. The team also found that higher levels of educational opportunity, specifically, are associated with better MSEL scores. This means that neighborhoods with more educational opportunities, like high quality center-based care, may provide more resources to get kids engaged in cognitively simulating activities and enhance their development.
“Prior work has focused on the role of socioeconomic disadvantages in child development. Our study aims to shift the conversation towards solutions for improving the environments that kids experience in early childhood to support their development and address inequalities,” said Mei Elansary, MD, MPhil, an Assistant Professor of Pediatrics at Boston University. “Given that race and ethnicity have been strongly associated with differential access to high opportunity neighborhoods, it is important to think about ways to promote access to these places for all families.”
1. What advantage do infants in neighborhoods with higher opportunity levels have?| A．They grow more quickly. | B．Their cognition develops better. |
| C．They have fewer health issues. | D．They have easier access to wealth. |
| A．By monitoring EEG patterns. | B．Through pediatric check-ups. |
| C．By having standardized tests. | D．By observing social interactions. |
| A．Its result. | B．Its purpose. |
| C．Its process. | D．Its application. |
| A．Update current economic conditions. | B．Invest more money on education. |
| C．Improve school facilities nationwide. | D．Create fair neighborhood opportunities. |
【推荐3】It’s a warm June afternoon, and in a group of bushes and trees, a bird sings. A small insect climbs over a leaf. The Muziekplein forest, next to an 18-story building and a railway line, is about the size of a basketball court; before it was planted in 2018, the area was a parking place. The forest is one of seven such extremely small forests in the Dutch city of Utrecht, and 144 across the Netherlands. By the end of this year, according to IVN Nature Education, the organization proposing the country’s initiative, there will be 200.
Since the first forest was planted in the Netherlands in 2015, the concept has become popular. Daan Bleichrodt, who launched IVN’s Tiny Forest initiative with the goal of making it easier for children to get into and connect with nature, said that he thinks it is popular because people are becoming more aware of major environmental challenges. It’s a very practical way to do something positive in the light of climate change and loss of biodiversity.
Jeroen Schenkels, a senior adviser for the city of Utrecht on green planning, said he sees the mini-forests as nature-based approaches that are able to help the city weather heat waves and improve water retention (保持). But one of the biggest interests is social. “One of the most important things is that they give people the opportunity to be involved in nature in the neighbourhood,” Schenkels said.
Between 2018 and 2020, 40 different plant and animal groups and 121 total animal species were found in the Muziekplein forest alone. According to Wageningen University researchers, across the 11 tiny forests in their study, volunteers observed 636 animal species. They also identified 298 plant species in addition to the original species planted in the plots. Maintenance of the forests occasionally involves removing aggressive weeds, but in general new plant species, such as wildflowers that appear, are allowed to grow.
1. What is special about the Muziekplein forest?| A．It is newly planted. | B．It sits in an urban area. |
| C．It grows along a railway. | D．It is shaped like a basketball court. |
| A．To make people realize environmental challenges. |
| B．To make nature more accessible to children. |
| C．To increase the Netherlands’ biodiversity. |
| D．To call for action on climate change. |
| A．Benefits of mini-forests in cities. | B．Ways to keep neighborhoods green. |
| C．Inspiration for planting forests in cities. | D．Importance of being exposed to nature. |
| A．By listing data. | B．By giving examples. |
| C．By doing experiments. | D．By making comparisons. |
【推荐1】As soon as we get past the age of 25, many of us immediately feel the urge to stop the signs of ageing — especially the visible ones. Men and women are now using topical “anti- ageing” creams, spa treatments and medical procedures to counter many of them. But while these methods can somewhat affect the way you look, ageing is an internal process. A group of scientists based out of the Stanford University School of Medicine have discovered that instead of being a smooth, continuous process, ageing surges (猛增) forward at three distinct stages of life: first, at the age of 34, then at age 60, and finally at 78.
The study, published in Nature Medicine, reveals that scientists can not only predict your age by studying the proteome (protein levels in the blood) but also determine which organs are ageing faster than the others, and which age-related diseases your body is more susceptible to. The study measured plasma proteins (血浆蛋白) collected from 4, 263 adults between the ages of 18 — 95 years and studied the changes in the proteome that occurred with age.
Their ultimate goal was to understand how to identify the changes associated with cardiovascular (心血管的) issues and age-related diseases like Alzheimer’s so that therapeutic treatments can be thought up to counter their onset while there’s still time.
Wyss-Coray and his workmates did not study protein samples from individuals but instead divided the participants into age groups. This helped them identify that ageing underwent sudden surges during three stages of life: young adulthood, late middle age and old age. The scientists were also able to isolate people who did not age according to their actual age. What’s more, the study also confirmed that men and women, who were equally represented in the study, age differently.
While these are still early discoveries and actual clinical applications, the scientists revealed, are at least 5 to 10 years away, the results seem to have a lot of potential. There could one day be a simple blood test that could study the protein levels and determine whether you are ageing appropriately or not.
Does this also mean that there could, one day, be a way of actually stopping the process of ageing altogether? You never know.
1. What did the scientists find?| A．Ageing can’t be avoided. | B．Preventing ageing can cure illnesses. |
| C．Ageing process quickens at three phases. | D．Humans can use some methods to look younger. |
| A．Mature. | B．Defenseless. | C．Responsive. | D．Addictive. |
| A．To pursue a forever young life. |
| B．To know more about life and death. |
| C．To offer possible treatments for age-related diseases. |
| D．To identify the differences between men and women. |
| A．Favourable. | B．Critical. | C．Unconcerned. | D．Doubtful. |
【推荐2】Just because a scientist puts a GPS tracking collar on a wild polar bear does not mean the animal will willingly keep it on. They can remove it, if one becomes annoying. But scientists have now found a way of using signals from those dropped collars to track the ice itself.
The scientists identified 20 collars that transmitted movement data consistent with ice drift (漂流) rather than polar bear motion between 2005 and 2015. The resulting records of how melting ice drifts in Hudson Bay are unique; there are no easily accessible on-the-ground sensors, and satellite observations often cannot accurately capture the motion of small ice sheets.
The team compared the removed collars’ movements to widely used ice-drift modeling data from the U. S. National Snow and Ice Data Center (NSIDC). Collar data indicated that the NSIDC model underestimates the speed at which ice moves around in Hudson Bay — as well as the overall extent of drift. Over the course of several months the model could diverge (偏离) from an ice sheet’s location by a few hundred kilometers, the scientists say.
This means the bears may be working harder, when moving against the direction of the ice, than scientists had assumed, “Since we’re underestimating the speed of drift, we’re likely underestimating the energetic effort of polar bears,” says Ron Togunov, who led the study.
The study reveals timely insight into how highly mobile ice moves. As melting increases in coming years, such ice will likely become more common farther north, in the central Arctic, says Andy Mahoney, a geophysicist at the University of Alaska, who was not involved in the study. Scientists had known NSIDC data could underestimate drift speeds, Mahoney says, but “any time we can find a data gap and plug it is a good thing.”
Plus, such data could improve predictions about how oil spills or other pollutants may spread in seas littered with drifting ice, says Walt Meier, a senior NSIDC research scientist. The findings may even influence future NSIDC models. “It'’s a really nice data set.” Meier says. “And certainly one we’ll take under consideration.”
1. What can a GPS tracking collar do?| A．Measure the depth of ice sheet. | B．Capture the movement of ice. |
| C．Describe the melting speed of ice. | D．Record the emotional state of bears. |
| A．It shows the ice moves more slowly from its original location. |
| B．It may reveal polar bears are not so energetic as before. |
| C．It indicates the ice is more likely to move south in the central Arctic. |
| D．It can help predict the location of some pollutants in seas. |
| A．Data Tells a Different Story | B．Wild Polar Bears’ Signaling |
| C．Insights into a Puzzling Aspect | D．Ice Is Taken under Consideration |
Using a web camera equipped in Jennifer’s Los Angeles apartment, the monitor in Phoenix tracked how frequently her eyes moved from the computer screen and listened for the secret sounds of a possible helper in the room. Her Internet access was locked-remotely-to prevent Internet searches, and her typing style was analyzed to make sure she was who she said she was: Did she enter her student number at the same speed as she had in the past? Or was she slowing down?
In the battle against cheating, this is the cutting edge and a key to encourage honesty in the booming field of online education. The technology gives trust to the entire system, to the institution and to online education in general. Only with solid measures against cheating, experts say, can Internet universities show that their exams and diplomas are valid-that students haven’t just searched the Internet to get the right answers.
Although online classes have existed for more than a decade, the concern over cheating has become sharper in the last year with the growth of "open online courses." Private colleges, public universities and corporations are jumping into the online education field, spending millions of dollars to attract potential students, while also taking steps to help guarantee honesty at a distance.
Aside from the web cameras, a number of other high-tech methods are becoming increasingly popular. Among them are programs that check students’ identities using personal information, such as the telephone number they once used.
Other programs can produce unique exam by drawing on a large list of questions and can recognize possible cheaters by analyzing whether difficult test question are answered at the same speed as easy ones. As in many university classes, term papers are scanned against some large Internet data banks for cheating.
1. Why was Jennifer watched in an online exam?| A．To correct her typing mistakes. |
| B．To find her secrets in the room. |
| C．To prevent her from slowing down. |
| D．To keep her from dishonest behaviors. |
| A．advanced technique | B．sharpening tool |
| C．effective rule | D．dividing line |
| A．they can attract potential students | B．they can defeat academic cheating |
| C．they offer students online help | D．they offer many online courses |
| A．checking the question answering speed |
| B．producing a large number of question |
| C．scanning the Internet test question |
| D．giving difficult test question |
| A．The Advantages of Online Exams |
| B．The High-tech Methods in Online Courses |
| C．The Fight against Cheating in Online Education |
| D．The War against the Booming of Online Education |
