High-resolution (高分辨率) satellite imagery has been used to map every single tree in Africa, showing a technique that could help improve the monitoring of deforestation (森林砍伐) across the world. Florian Reiner at the University of Copenhagen, Denmark, and his colleagues used images from sate lies to map canopy (树冠) across the entire African continent.
Modern sate lies usually catch tree canopies at a resolution of 30 meters — fine for measuring the size of forests, but less good at mapping individual trees. The satellite data Reiner and his colleagues used had a resolution of 3 meters, enabling the study to map all trees, including those not part of a forest.
The results suggest that 30 percent of all trees in Africa aren’t in a forest and instead are across farmland, savannah and urban areas. “Many countries in Africa lack thick forests, but have a lot of trees.” says Reiner. “These trees are extremely important to the local ecosystems, the people and the economy. By tracking every single tree, researchers can start to monitor how these trees are coping with climate change or whether they are sensitive to deforestation.” It could also improve the monitoring of reforestation efforts, which are growing in popularity as a way of removing carbon dioxide from the atmosphere.
“At a local level, being able to consistently monitor when and where trees are disappearing or reappearing can lead to more actionable insights,” says John Francis at the Alan Turing Institute in London.
“The study is a proof of concept rather than a map ready for immediate commercial use,” says Reiner. “It’s research work. It’s showing what could be done,” he says. But he is already working with colleagues to scale up the tracking approach to cover the entire global canopy: “We’re hoping that this will be seen as a way forward in monitoring tree resources.”
1. Why is high-resolution satellite imagery used to map every single tree?A.To know the exact height of the tree. |
B.To have a clear picture of the canopy. |
C.To help monitor the deforestation. |
D.To improve the satellite technology. |
A.Doubtful. | B.Disapproving. | C.Indifferent. | D.Favorable. |
A.Protect the trees only in Africa. |
B.Put the map into commercial use. |
C.Track the entire global canopy. |
D.Improve the imagery technology. |
A.Ways to Measure the Size of Forests in Africa |
B.Coping with Climate Change by Tracking Every Single Tree |
C.A Map from the Satellite Ready for Immediate Commercial Use |
D.High-resolution Satellite Imagery Used in Monitoring Deforestation |
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【推荐1】The Intergovernmental Panel on Climate Change released a report stating that the world is quickly running out of time to keep global warming below 1.5 degrees Celsius. To get there, the world would have to cut current emissions by 45 percent by 2030.That sounds absurdly unlikely.
But before we give in to hopelessness,we should remember that the technology to deal with climate change is going along at high speed. The largest source of U. S. carbon emissions is transportation,and a Green New Deal for motor vehicles would be quite straightforward. The reason is simple:with some government subsidies (补贴), electric cars and buses are now cost-competitive with fossil-fuel vehicles. Electric buses have made the greatest speed into the market, because they are a logical choice for electrification. By the end of 2018, electric vehicles were replacing about 280,000 barrels of oil demand per day — about 84 percent of which was mainly consumed by buses.
The electric car market is also reaching maturity, with appealing designs, longer range, and a quickly-expanding rapid charging network in many countries. It’s worth emphasizing that most of the infrastructure (基础设施) necessary to recharge electric vehicles already exists. People often tend to think that we need to replace every gas station, but actually all homes and businesses already have an electrical connection which can be easily improved for fast charging. All that is needed to go fully electric is enough battery capacity and fast charging stations to deal with long trips.
Now America would have to repair its electricity production, freight rail, shipping, and so on to fully decarbonizes (脱碳) the transportation sector, which will be considerably more difficult than simply rooting out fossil fuel vehicles from the market.
But greening America’s vehicle would be straightforward, relatively cheap, and a huge step forward on climate. The politics of climate change are so fearful that being hopeless can seem logical, but the first step to achieving a tough goal is the confident belief that it can be done. And this particular step wouldn’t even be that tough.
1. How’s the goal of keeping global warming below 1.5 Celsius according to Paragraph 1?A.Reasonable. | B.Safe. |
C.Realistic. | D.Impossible. |
A.are cost-competitive with government subsidies |
B.run at a greater speed on the road |
C.deal with longer trips |
D.look more appealing |
A.Replace as many as gas stations. |
B.Build more infrastructures for recharging. |
C.Make businesses have electrical connections. |
D.Solve the problem of long trips. |
A.Negative. | B.Supportive. |
C.Uncertain. | D.Indifferent. |
【推荐2】Most people don't think much about the food scraps they throw away; however, researchers in Tokyo have developed a new method to reduce food waste by recycling discarded fruit and vegetable scraps into robust construction materials.
Worldwide industrial and household food waste amounts to hundreds of billions of pounds per year, a large proportion of which
“Our goal was to use seaweed and common food scraps to construct i materials that were at least as strong as concrete,” explains Yuya Sakai, the senior author of the study. “But since we were using edible food waste, we were also interested in determining whether the recycling process impacted the flavor of the original materials.”
The researchers borrowed a “heat pressing” concept that is typically used to make construction materials from wood powder, except they used vacuum-dried, pulverized food scraps, such as seaweed, cabbage leaves, and orange, onion, pumpkin, and banana peels as the construction powders. The processing technique involved mixing the food powder with water and seasonings, and then pressing the mixture into a mold at high temperature. The researchers tested the bending strength of the resulting materials and monitored their taste, smell and appearance.
“With the exception of the specimen obtained from pumpkin, all of the materials exceeded our bending strength target,” says Kota Machida, a senior collaborator. “We also found that Chinese cabbage leaves, which produced a i material over three times stronger than concrete, could be mixed with the weaker pumpkin-based material to provide effective rein for cement.”
The new, robust materials kept their edible nature, and the addition of salt or sugar improved their taste without reducing their strength. Furthermore, the durable products resisted rot, fungi, and insects, and experienced no appreciable changes in appearance or taste after exposure to air for four months.
Given that food waste is a global financial burden and environmental concern, it is crucial to develop methods for recycling food scraps. Using these substance to prepare materials that are stronger enough for construction projects, but also maintain their edible nature and taste, opens the door to a wide range of creative applications.
1. Why do the researchers search for new ways to recycle organic materials?A.Because the construction of robust material needs much food waste. |
B.Because food waste is both costly and environmentally unfriendly. |
C.Because they want to make a fortune by recycling the food waste. |
D.Because the amount of food waste is too large to store at the moment. |
A.Contains. | B.Processes. | C.Presses. | D.originate. |
A.All the materials obtained from food waste surpass researchers ' strength target. |
B.The material produced from Chinese cabbage leaves is two times stronger than concrete. |
C.There is a lot of room for creative use of this technology. |
D.The new materials are strong enough for construction projects, but fail to maintain their original taste. |
A.A tourist brochure. | B.A recipe book. | C.A biography book. | D.A science magazine. |
【推荐3】Nowadays, the world is slowly becoming a high-tech society and we are now surrounded by technology. Facebook and Twitter are innovative tools; text messaging is still a somewhat existing phenomenon and even e-mail is only a flashing spot on the screen when compared with our long history of snail mail. Now we adopt these tools to the point of essentialness, and only rarely consider how we are more fundamentally affected by them.
Social media, texting and e-mail all make it much easier to communicate, gather and pass information. But they also present some dangers. By removing any real human engagement, they enable us to develop our abnormal self-love without the risk of disapproval or criticism theatrical metaphor (隐喻), these new forms of communication provide a stage on which we create our own characters, hidden behind a fourth wall of tweets, status updates and texts. This unreal state of unconcern can become addictive as we separate ourselves a safe distance from the cruelty of our fleshly lives, where we are imperfect, powerless and insignificant. In essence, we have been provided not only the means to be more free, but also to become new, to create and protect a more perfect self to the world. As we become more reliant on these tools, they become more a part of our daily routine and so we become more restricted in this fantasy.
So it is that we live in a cold era, where names and faces represent two different levels of closeness, where working relationships occur only through the magic of email and where love can start or end by text message. An environment such as this reduces interpersonal relationships to mere digital exchanges.
Would a celebrity have been so daring to do something dishonorable if he had had to do it in person? Doubtful. It seems he might have been lost in a fantasy world that ultimately convinced himself into believing the digital self could obey different rules and regulations, as if he could continually push the limits of what’s acceptable without facing the consequences of “real life.”
1. The author compares e-mail with snail mail to show ________.A.the influence of high-tech on our life | B.the history of different types of mails |
C.the value of traditional communications | D.the rapid development of social media |
A.Destroying our life totally. | B.Posing more dangers than good. |
C.Helping us to hide our faults. | D.Replacing traditional letters. |
A.Sheltering us from virtual life. | B.Removing face-to-face interaction. |
C.Leading to false mental perception. | D.Making us rely more on hi-tech media. |
A.Technologies have changed our relationships. |
B.The digital world is a recipe for pushing limits. |
C.Love can be better conveyed by text message. |
D.The digital self need not take responsibility. |
【推荐1】China is expected to restructure its industry and energy mix during the 14th Five-Year Plan period(2021-2025)to lay a solid foundation for peaking carbon dioxide emissions before 2030, a climate change expert has said.
The best possible situation is that China will achieve zero growth in coal consumption during the period, and see usage peak and begin to decline by 2025, according to He Jiankun, deputy director of China's national expert committee on climate change.
During the period, China should promote the development of the digital, high-tech and modern services industries, while the expansion of high energy-consuming industries such as the steel and chemical industries should be controlled, said the expert.
That is because China is still in the industrialization and urbanization stage and requires significant infrastructure construction, He added, noting that a large portion of carbon emissions in China are created during the building process rather than being a result of the people's consumption needs.
The adjustment and upgrading of the industrial structure will be promoted so that energy consumption per unit of GDP will drop rapidly and total energy consumption growth will be controlled, He said.
China has announced that it will make efforts to bring carbon dioxide emissions to a peak before 2030 and become carbon neutral(中和)before 2060.
The carbon emissions target means a nationwide peak by the deadline, but at the regional level, the progress will surely be staggered given differences in resources and economic development stages, said He, stressing the need to take a diverse and inclusive approach that coordinates(协调)emission cuts with development.
Relatively developed regions in east China are expected to be among the first to reach a peak as they take the lead in economic transformation, and another group of front-runners will be from the country's renewable energy-rich southwest, said He.
Since the carbon peak and carbon neutrality targets were set, local governments have engaged in making plans at the provincial and city level, the expert said.
He urged local authorities to "suppress the impulse" to expand capacity in energy-intensive heavy and chemical industries, and speed up the formation of a green, low-carbon circular industrial system.
1. What are the two goals of 2030 and 2060 respectively?A.Peak carbon emission and achieve carbon neutrality. |
B.Suppress the impulse to expand and boost the green system |
C.Adjust the industrial structure and upgrade the structure |
D.Relieve poverty and achieve the whole nation's well-being. |
A.speed up in efficiency | B.influence positively | C.perform slowly | D.vary in time |
A.China will promote low-carbon industries. | B.China will improve its industrial structure. |
C.China will control the development of heavy industry | D.China will put emission cuts first in its development. |
A.Fashion | B.Reader's Digest | C.China Daily | D.Science Magazine |
【推荐2】Natural silence — the kind when you hear nothing but the sound of nature around you — is becoming increasingly scarce. The noise of man-made can be heard even in the remote corners of national parks and deep in the Arctic Ocean.
This is having some troubling effects. In humans, noise pollution has been linked to physical, mental health problems and cognitive impairment (认知功能障碍) in children. In wildlife,it’s disturbing navigation, pairing, communication and can cause hearing loss. “We’re losing the ability to listen to nature without noise pollution,” says sound recordist Matt Mikkelsen. He’s part of the non-profit organization Quiet Parks International, which aims to identify and preserve the planet’s last quiet places.
Recently, this took him to Boundary Waters Canoe Area Wilderness in northeastern Minnesota. No cars, motor boats, electricity or telephone lines are allowed in the one-million-acre area,making it a strong candidate for Quiet Park status. But listening back to the recording, Mikkelsen can hear the low hum (嗡鸣声) of a commercial plane flying far away.
Quiet Parks hasn’t yet decided if Boundary Waters meets its criteria — it’s one of 260 potential sites around the world that the organization is currently exploring. The team will analyze the sound recordings from each location and consider them alongside other data.
In recent years, the world has been getting louder, with cities and towns expanding and an increasing number of noises from cars, airplanes or ships. But during the COVID-19 pandemic (流行病), there has been momentary delay.In2020,global air travel was down by 60% and road transport decreased by almost half. Scientists in Europe found that noise caused by humans fell by up to 50% after lock downs were carried out.
“People enjoyed the silence,” says Mikkelsen. “There were no airplanes in the sky and cars weren’t on the street. It was an incredible thing to be able to hear the world, all of a sudden, free from noise pollution,” he says. Since the start of the pandemic, Quiet Parks says it has experienced a huge increase in interest for quiet places. “I hope that we can take that desire for a world with less noise forward,” says Mikkelsen, “and appreciate the spots we have, where we can go and not experience noise pollution.”
1. What does the underlined word “scarce” probably mean in paragraph 1?A.Special. | B.Rare. | C.Common. | D.Typical. |
A.Causes of hearing loss. |
B.Tips on protecting the nature. |
C.Harmful effects of noise pollution. |
D.Unidentified problems from human beings. |
A.The sound recordings. | B.Global air travels. |
C.Quiet Parks’ criteria. | D.Data of the pandemic. |
A.A book review. | B.A travel guide. |
C.A business plan. | D.A science report. |
【推荐3】It is a well-known fact that plastic bottles, which take hundreds of years to rot, are harmful to our environment. However, efforts by environmentalists to encourage consumers to switch to alternatives, like water fountains or reusable bottles, have not been very effective. The U.S. alone uses over 50 million plastic bottles annually, 80% of which end up in landfills.
To try to stop that, Rodrigo García González, Pierre Paslier and Guillaume Couche from the Imperial College London have been working on a revolutionary solution — water wrapped inside an eatable container made mostly from seaweed. All the customer has to do to relieve his/her thirst is pop the entire drop into the mouth.
The inventors, who have been working on the Ooho bubble since 2014, use a simple two-step cooking process called spherification (球化) to create the delicate container. They begin by dipping a frozen ball of water or juice into a chemical solution (溶液). This helps form a layer around the liquid. The ball is then absorbed in a solution made from seaweed extract. This creates a second layer, helping strengthen the structure so that the water or juice does not leak. In addition to saving our environment, the biodegradable (可降解的) packaging costs just two cents each, making it cheaper to produce than plastic.
After three years of perfecting the design, the inventors, who recently raised over 1 million USD from a financial activity, are ready to bring the Ooho bubble to local market. However, there are a few challenges that still need to be overcome before the product’s launch. In addition to getting accustomed to the taste of the covering, each eatable container contains just a mouthful of water, requiring consumers to drink multiple bubbles to relieve their thirst. There is also the issue of finding an eco-friendly packaging to transport the bubbles so that they remain clean and do not burst. Hopefully, the inventors will find ways to handle the issues so that we can reduce, or perhaps even remove, plastic bottles.
1. Why was the Ooho bubble created?A.To test a newly-designed material. | B.To change consumers’ drinking habit. |
C.To reduce pollution caused by plastic. | D.To take a share of drinking water industry. |
A.Solve some specific problems of the product. | B.Collect more money to expand production. |
C.Distribute the Ooho bubble to global market. | D.Advertise the advantages of the Ooho bubble. |
A.Uncaring. | B.Doubtful. | C.Confident. | D.Opposed. |
A.Scientists Work out a New Kind of Water |
B.Plastic Bottles Will Be Replaced by the Ooho Bubble |
C.Environmental Pollution is Expected to Be Solved |
D.The Ooho Bubble Aims to Remove Plastic Bottles |
【推荐1】Microplastics are everywhere in our environment. It's hardly surprising that the tiny fragments have also been found in humans. A new study shows that Americans are consuming as many as 121,000 particles each year.
Measuring 50 to 500 microns in length, microplastics come from a variety of sources, including large plastics that break down into smaller and smaller pieces. Therefore, much remains unknown about the common existence of these materials within the human body, as well as their impact on human health.
Hoping to fill in some of these gaps, a research team led by Kieran Cox, a PhD candidate at the University of Victoria, looked at 26 papers assessing the amount of microplastics in commonly consumed food items, among which are seafood, sugars, salts, honey, alcohol and water. The team also evaluated the potential consumption of microplastics through inhalation (吸入)using previously reported data on microplastic concentrations in the air and the Environmental Protection Agency's reported respiration rates. Based on these data, the researchers calculated that our annual consumption of microplastics via food and drink ranges from 39,000 to 52,000 particles. When microplastics taken in through inhalation are taken into account, the range jumps to between 74,000 and 121,000 particles per year.
The authors of the study found that people who drink exclusively from plastic water bottles absorb an additional 90,000 microplastics each year, compared to 4,000 among those who only consume tap water. "This shows that small decisions, over the course of a year, really matter and have an impact." Cox says. The new study, according to its authors, was the first to investigate "the accumulative human exposure" to microplastics. But in all likelihood, the research tells only a small part of the entire story. Collectively, the food and drink that the researchers analyzed represent 15 percent of Americans' caloric intake. The team could not account for food groups like fruits, vegetables and grains because there simply is not enough data on their microplastic content.
For those worried about microplastic consumption, cutting down bottled water is a good place to start. But to the heart of the problem, we have to stop producing and using so much plastic.
1. What makes it difficult to know microplastics commonly exist in the human body?A.The quality. | B.The quantity. |
C.The shape. | D.The size. |
A.By studying papers. | B.By comparing the impacts. |
C.By analyzing the data. | D.By conducting experiments. |
A.Drinking less plastic bottled water helps to take in fewer microplastics. |
B.The study is among the earliest to investigate human exposure to microplastics. |
C.Cox's team gained comprehensive information of microplastics taken in by humans. |
D.People consume 74,000 to 121,000 particles of microplastics per year from food and drink. |
A.The Potential Problems of Microplastics |
B.Microplastics Coming From Various Sources |
C.Microplastics Found Within Human Bodies |
D.The Impact of Microplastics on Human Health |
【推荐2】It’s not often you get information about a destination from a heavy metal band, but in Debrecen, Hungary’s second largest city, locals are used to having to make a noise to get heard.
Just off the historic center, Roncs bar is a pub that also hosts live music. It has the atmosphere of a student party in an old building that might soon be knocked down.
Roncs is owned by Hungary’s best-known heavy metal rock band, Tankcsapda. Sometimes referred to as the “Hungarian Metallica”, the band has taken a type of music that is famous worldwide and-through lyrics, album covers, and an annual New Year’s party and concert-made it all about their home city.
It’s perhaps fitting that Tankcsapda should be seen as ambassadors for Debrecen — the city sometimes needs loud heavy metal rock music to get noticed. “Foreigners think that Hungary is Budapest and there’s nothing else,” is a familiar saying on Debrecen’s streets.
Debrecen has, at times, been more important than the current seat of power, with locals claiming it takes over in times of trouble.
That doesn’t quite add up.
Debrecen survived an attack from the Mongols in the 13th century, the Black Death, 150 years of struggle against the Ottomans and numerous conflicts, and yet it has still only briefly been the country’s capital twice. This happened for the first time after a short-lived revolution in 1849, and for a second time at the end of World War II.
Today, Debrecen may not be well known to tourists, but that only adds to the charm of this relaxed city. It’s a small place; the historical center is sized for strolling (散步) and regular cafe stops. There’s also a view of Debrecen’s mix of architectural styles, a result of the frequent large fires that back in the 19th century led the city’s students to form one of Europe’s first-ever fire brigades (消防队).
You can also see traditional weathercocks from the rooftops, featuring Islamic star and crescent moon symbols that once advertised to Ottoman invaders that the city preferred trading to fighting.
Trade meant that Debrecen’s skilled people became very successful and the city became famous for-among other things-fine foods, hats and clay pipes. In the early 19th century, 10 million clay pipes were reportedly made a year, with thousands bought for Britain’s navy.
1. What do Debrecen citizens expect Tankcsapda to do?A.Introduce heavy metal music to Hungary. |
B.Hold parties featuring live heavy metal music shows. |
C.Try to make Debrecen known with its music. |
D.Create a unique type of heavy metal music. |
A.Because they feel their city is too quiet and relaxed. |
B.Because they dislike it that the world only knows Budapest in Hungary. |
C.Because they think it helps create a powerful image of their city. |
D.Because all kinds of music bars bring their city alive. |
A.Styles. | B.Conditions. |
C.Atmosphere. | D.Climate. |
A.Debrecen actually is more important than Budapest. |
B.Debrecen is a place which is worth visiting. |
C.Debrecen citizens love music and create their unique culture. |
D.Debrecen citizens are proud of their culture and history. |
【推荐3】People who drink a lot of sugary drinks have a high risk of developing cancer, researchers announced last week. However, the evidence cannot yet confirm a direct connection between the two. The researchers said the findings of a large study in France suggest that limiting the amount of sugar-sweetened drinks may help reduce the number of cancer cases. Drinking sugary drinks has become more common worldwide in the last several decades. Sugar drinks are linked to obesity-the condition of being extremely overweight-which increases a person’s cancer risk.
The study was published in The BMJ British medical journal. It looked at data from just over 100,000 French adults-21 percent of them men and 79 percent women. The researchers noted how many sugary drinks each of them had, and followed them for up to nine years-between 2009 and 2018. The researchers appraised their risk for all types of cancer, and some individual ones such as breast, colon and prostate cancers.
The scientists found that a 100 milliliters increase in sugary drinks was linked to an 18 percent increased risk of overall cancer and a 22 percent increased risk of breast cancer. The researchers looked at those who drank fruity juices and those who drank other sweet drinks. Both groups, they found, showed a higher risk of cancer overall.
For prostate and colorectal cancers, no link was found. The researchers said this might have been because there was only a limited number of cases of these cancers in the study group.
Experts not directly involved in the work said it was a well-run study, but noted that its results could not establish cause and effect. Amelia Lake is an expert in public health nutrition at Britain’s Teesside University. She said that while this study does not provide a definite cause and effect between sugar and cancer, it does add to the importance of efforts to reduce sugar intake. “The message from the totality of evidence on excess sugar tonsureption and various health outcomes is clear,” she said.
1. What did the study find?A.Sugary drinks directly lead to cancer. |
B.Heavy sugary drinks might be linked with cancer. |
C.Obesity mainly results from sugary drinks. |
D.Cancer is not necessarily caused by obesity. |
A.Controlled | B.Evaluated. |
C.Determined. | D.Documented. |
A.By making comparison. |
B.By giving different opinions. |
C.By using actual figures. |
D.By following the order of time. |
A.More evidence needs to be found in the future. |
B.The researchers should follow more people. |
C.Reducing sugar consumption needs great efforts. |
D.Cutting down the amount of sugar is important. |
Trees around us are extremely important and have always been necessary for improving the human conditions. Our existing forests and trees we plant work to make a better world.
Trees produce oxygen
Carbon dioxide is a global warming suspect.
A.We could not exist as we do if there were no trees |
B.Trees help clean the sky |
C.A forest is a carbon storage area that can lock up as much carbon as it produces |
D.Trees control noise pollution |
E.Man has been planting trees to make the planet a more beautiful world |
F.The modern human community has other more practical reasons to admire and honor trees |
G.Trees can either store harmful pollutants or change the pollutants into less harmful forms |
【推荐2】A hungry fly speeds through a forest. It smells nectar (a liquid that insects feed on) and lands on a green leaf. It starts to drink the sweet liquid. Suddenly, the fly's world turns green. The two sides of the leaf close against each other. Long green teeth lock together around it. The fly has been caught by a Venus flytrap. There is no escape.
The Venus flytrap is perhaps the most famous killer plant. However, scientists have only recently started to understand how it hunts and eats. After years of study, plant scientist Alexander Volkov believes he now knows the Venus flytrap's secret. “This,” says Volkov," is an electrical plant."
There are three small hairs along each of the Venus flytrap's two leaves. When an insect touches a hair, it creates an electrical signal in the leaf. The insect can continue feeding—for now. But if it touches another hair within 20 seconds, the trap snaps shut. This system allows the plant to tell the difference between a drop of water, for example, and a moving creature.
Once trapped, an insect has little chance of survival. Instead of nectar, the Venus flytrap now releases a different liquid —one that slowly eats away at the insect. Ten days later, almost nothing is left. The plant's leaves open again, and the Venus flytrap is ready for its next meal.
Besides the Venus flytrap, there are around 700 species of killer plants around the world. Some are deadly. Sundews catch insects using a sticky liquid on the end of long hairs. A butterwort's leaves are covered with tiny, gluey hairs that trap small insects. Pitcher plants have long tubelike leaves into which insects fall and die. Some pitcher plants are large enough to catch and eat small animals like frogs and mice.
1. What is special about the Venus flytrap?A.Its trap closes very slowly. | B.It has to feed on flies. |
C.It produces electrical signals. | D.It just makes one kind of liquid. |
A.To explore how the insect survives. |
B.To explain how the Venus flytrap works. |
C.To describe different types of killer plants. |
D.To introduce an experiment carried out on a plant. |
A.The sundew. | B.The butterwort. |
C.The pitcher plant. | D.The Venus flytrap. |
A.What meals a Venus flytrap prefers. |
B.What the features of deadly plants are. |
C.Where the deadly plants are found. |
D.How other killer plants catch insects. |
【推荐3】Fig trees are native to Europe around the Mediterranean Sea, Asia and Arica, but they can grow in much cooler climates.
Once big enough, fig trees can accept temperatures even a few degrees below freezing. Some kinds of fig trees do better in such environments than others.
Depending on the weather and pruning (修剪), a fig can grow into a bush or a tee. Bushes with several stems (茎) growing from the ground do best if covered for the winter.
One popular method for burying trees for their protection involves digging a narrow, shallow area.
Next, push a shovel (铲子) into the soil about a half-meter from the trunk (树干) on the side opposite the hole. Lift that side of the tree’s root ball out of the ground. Then, gently push the tree toward the hole.
Pack soil around the exposed side of the roots, and around the length of the tree. Load soil over the tree. Make it at least 30 centimeters deep. You will need more soil than you removed from digging.
A.And in this area the tree can be laid. |
B.All kinds of the trees could use protection. |
C.You can also cover, or wrap, the tree instead. |
D.And bend it around the bottom part of the tree. |
E.When it is lying fat, cover the tree with plastic. |
F.Trees with a single trunk can be buried or covered. |
G.Remove the cover on the tee on a cloudy day in early spring. |