1 . 400 million tons of plastic are generated annually, most of which comes from single-use plastic While countries are making progress in reducing this waste through paper bags and straws, there are still applications where the properties of plastic are necessary.
Transparent (透明的) wood is an alternative for such applications and is highly preferred since it prevents the harm of petroleum-derived (石油衍生的) plastic products. German scientist Siegfried Fink first created transparent wood in the year 1992, and over the past three decades it has been significantly improved by other researchers as well.
In its natural form, wood is not transparent. However, researchers have found that removing lignin, a naturally occurring biopolymer that provides structural support for the plant tissue, can make it transparent. To do so, the wood is soaked in a warm solution consisting of multiple chemicals, followed by boiling it in another solution. This removes the lignin completely and turns the wood white. However, the space that was occupied by lignin needs to be filled up to maintain structural integrity. This process is done by using a resin (树脂) at a temperature of 185 Fahrenheit (85℃).
The final product can have as much as 90 transparency, and it doesn’t break easily. More importantly, it is more biodegradable than glass or plastic.
While transparent wood isn’t commercial yet, it has been employed in a wide variety of applications ranging from construction to energy storage, making flexible electronics and packaging.
The researchers at the Indian Institute of Technology ( IIT) conducted a life-cycle analysis (LCA) of transparent wood to determine the environmental impact of its production and end-of-life (EOL) cycle. The study found that using hydrogen peroxide for delignification, followed by using epoxy for infiltration, was the most eco-friendly. When scaled up for industrial production, the former method would lower electricity consumption by as much as 98. 8 percent.
EOL analysis showed that transparent wood had a reduced ecological impact compared to polyethylene (聚乙烯), paving the way for it to be commercially adapted to replace the petroleum-based material.
1. Why is transparent wood preferred compared to plastic?| A．It is easier to make. | B．It is environmentally friendly. |
| C．It can be used longer. | D．It can be used repeatedly. |
| A．The natural form of wood. | B．The importance of chemicals. |
| C．How transparent wood is made. | D．How lignin keeps wood strong. |
| A．It can be recycled. |
| B．It will replace plastic soon. |
| C．The most eco-friendly way to produce it. |
| D．Potential damage caused by it to the environment. |
| A．Promising. | B．Difficult. | C．Profitable. | D．Uncertain. |
2 . In the U. S., people eat more protein than they need to, which might not be bad for human health, but does pose a problem for the country’s waterways. The nation’s wastewater is loaded with the leftovers from protein digestion: nitrogen compounds(氯化合物) that can feed harmful algal blooms(藻华) and pollute the air and drinking water.
Maya Almaraz, a biogeochemist at the University of California, Davis, and her team wanted to see how much of this nitrogen entered into the U. S. wastewater system because of a protein-heavy diet. The researchers found that the majority of nitrogen pollution present in wastewater—some 67 to 100 precent—is a by-product of water people consume.
Once it enters the environment, the nitrogen can have a series of ecological impacts. It helps algae grow much faster than they would normally, which is harmful to humans, other animals and plants. And when the algae eventually die, the problem is not over. Microorganisms(微生物) that feed on dead algae use up the oxygen in the water, leading to “dead zones,” where many species simply cannot survive, in rivers, lakes and oceans.
Although it is possible to treat algal blooms, many of the current methods are not always effective at getting rid of all of the harmful growth. Some of these methods can even lead to additional pollution. So the best strategy for dealing with the effects of nitrogen pollution is prevention, says Patricia Glibert, an ocean scientist at the University of Maryland. Almaraz and her team suggest that controlling nitrogen pollution could be approached more quickly with a change in eating habits that could save billions of dollars in the long term.
1. Which aspect of Americans’ diet does Almaraz’s research focus on ?| A．Its variety. | B．Its effect. | C．Its make-up. | D．Its amount. |
| A．No oxygen for many species. | B．Death of lots of healthy algae. |
| C．Microorganisms’overconsumption of nutrients. | D．Poisonous chemicals released by harmful algae. |
| A．They are costly. | B．They may kill all algae. |
| C．They are slow to take effect. | D．They may cause secondary pollution. |
| A．It is high time to treat wild algae growth. | B．Eating too much protein harms the planet. |
| C．Prevention is better than cure in treating air pollution. | D．Researchers find solutions to the wastewater problem. |
3 . These days more and more people tend to buy man-made trees for Christmas, because they think they are good for the environment. But is it true? Which is more environmentally friendly—real or man-made? The simple answer is: it depends.
Real trees that still have their roots have little carbon footprint (碳足迹). They can be planted, brought inside for the Christmas period and then replanted.
But things are more complex for other trees.
Britain’s Carbon Trust estimate (估计) that a two-meter tall tree that doesn’t have roots has a carbon footprint of between 3.5 kg CO2e and16 kg CO2e depending on whether it is burnt—which is less polluting——or finds its way to a landfill (垃圾填埋场). “Unfortunately, we still see a lot of trees going into landfill,” says Sophie Neuberg, a member of Friends of the Earth. “And that’s very bad for the environment because they break down very slowly and create methane which is a greenhouse gas.”
The picture for plastic trees isn’t so encouraging. The Carbon Trust estimate a carbon footprint of around 40 kg CO2e for a two-meter tree, but its beauty is that it can be reused.
“It’s a good idea to get a good quality one that you can use for many years. Someone I know has had their plastic tree for 20 years,” Neuberg says.
This tendency toward reuse of plastic treess is supported by research published by the American Christmas Tree Association (ACTA) who estimate that 85% of US families with a man-made tree will reuse it and that on average man-made trees are reused for 11 years.
Jami Warner, director of ACTA repeats Neuberg’s advice. “Quality man-made trees are very easy to break down and very easy to store,” Wrner says. “If you take good care of it you can use it season after season or you can donate it to a good organisation.”
However, if you want a truly green Christnnas, you can simply replace the tree with the plants already in your house and decorate them for Christmas.
1. Why do people tend to buy man-made Christmas trees now?| A．They think it costs less. |
| B．They find it more convenient. |
| C．They consider it more decorative. |
| D．They believe it is more eco-friendly. |
| A．Burning it. | B．Reusing it. |
| C．Throwing it. | D．Replanting it. |
| A．Buying a good quality plastic tree. |
| B．Planting a tree in a pot and reusing it. |
| C．Using plants to replace Christmas trees. |
| D．Ignoring the tradition and canceling the tree. |
| A．Business. | B．Education. |
| C．Health. | D．Environment. |
4 . In elementary school, I earned my Girl Scout Bronze Award by planting a butterfly garden. When I got a little older, I earned my Girl Scout Silver Awar by bringing an art program to struggling refugees (难民). But when it was time for me to go for my Girl Scout Gold Award, there was something even bigger affecting us all that I had to focus on.
People talk about damage to our environment and argue about who’s to blame, but the thing is, we don’t have time for all that. The earth is in danger, and that means all of us are in danger. That’s why I founded Project ReefLove, an awareness and educational campaign (活动) that teaches kids one super simple and easy way we can help protect coral reefs, which are the rainforests of the sea.
Lots of creatures, from sea turtles to sharks to starfish, depend on coral for survival, and the reefs help prevent beach erosion. Coral is really important—but the chemical sunscreens a lot of people wear are poisoning it and threatening the whole ecosystem. Saving coral can seem like a huge undertaking, but once you know how big a difference something simple like switching to a mineral sunscreen or wearing a rash guard instead of using chemical SPF makes, you’ll realize it is not so hard after all.
The first step, I knew, had to be education. So I went to the source: kids. From my own experience growing up in Girl Scouts, I know there’s nothing stronger than the passion of young people. If you get a little kid excited about saving the environment, their parents, grandparents, teachers, and others in earshot are going to hear about it, too!
So far, the Project ReefLove message has directly reached more than 11,000 people—and I’ve been excited to see lawmakers take action to do their part, too. Hawaii just outlawed sunscreens that are toxic (有毒的) to reefs, and I’m hoping other states will follow its lead.
1. What did the author plan to do for her Girl Scout Gold Award?| A．Save kids in danger. | B．Build a butterfly garden. |
| C．Help refugees to make a living. | D．Teach kids how to protect coral reefs. |
| A．Saving coral. | B．Using chemicals. |
| C．Giving up sunscreens. | D．Protecting sea creatures. |
| A．The influence of Girl Scouts. |
| B．How family education affects kids. |
| C．The importance of protecting the environment. |
| D．Why the Projcct ReefLove focuses on kids’ education． |
| A．To encourage more kids to join Girl Scouts. |
| B．To tell readers how she’s saving coral reefs. |
| C．To show that the Project ReefLove is powerful. |
| D．To ask lawmakers to pay attention to coral reefs. |
5 . Scientists have found something strange has been happening among sensitive bird species in the Brazilian Amazon in recent years. Not only were the birds declining in number, but their bodies were also shrinking in size. “We found that size was not only shrinking for those sensitive species-it was declining for everyone, “said researcher Vitek Jirinec of Louisiana State University. Jirinec’s findingsare contained in a new study published in the journal Science Advances last Friday.
The study examined 77 species over a 40-year period, during which time the rainforest had become warmer. It found they were rapidly evolving perhaps because smaller birds remove heat more efficiently as they have more surface area in relation to volume. Brian Weeks of the University of Michigan explained it this way: “You could imagine lots of little ice cubes in a glass of water, as opposed to one big ice cube, and the little ice cubes melt faster because smaller things have larger surface area-to-volume ratios(比)，so they exchange heat more quickly. “Weeks didn’t work on this particular study, but he did research the size of more than50 species of migratory (迁徙的) birds in North America a few years back. He too found that nearly all of them were shrinking decade by decade.
The two studies strengthen the idea that birds all over the planet, migratory or not, may be changing shape due to a warming climate. Weeks said these sorts of changes should concern all of us. “All around the world, people depend on natural systems. Complete natural systems provide more economic benefits to humanity than the entirety of the world’s GDP, so they matter to you whether or not you know it, Weeks said. Jirinec thought the timing of his paper’s publication could not be more fitting. The study came out on the same day as the conclusion of the UN climate change conference in Glasgow. So those results really stressed the common consequences of the actions for the planet.
1. What was a cause of the birds becoming smaller in size?| A．The decrease of birds’ number. | B．The sensitiveness of birds. |
| C．A warming climate. | D．The development of birds. |
| A．By example and comparison. | B．By analyzing the data. |
| C．By giving enough evidence. | D．By observation and research. |
| A．Dangerous. | B．Concerning. |
| C．Demanding. | D．Fantastic. |
| A．To introduce two studies. | B．To explain a natural phenomenon. |
| C．To praise the conference in Glasgow. | D．To make people focus on climate change. |
The average temperature of the Earth’s surface has increase by 0.85°C in the last hundred years. It’s too late to reverse the changes. Now we have to find ways
However, we can reduce greenhouse gas missions or make
emissions from animals are
And rich countries have the resources to adapt to
And countries where lack of water is a problem like Australia, China, and Spain, have built plants,
7 . Manta rays (魔鬼鱼)are some of the creatures in the ocean who allow divers to swim right up to and interact (互动) with them. Unfortunately, these gentle animals are in big trouble. Since 2011, manta rays have been listed as a threatened species worldwide.
Peru, a country in South America, recently took a big step to protect giant manta rays: It banned fishing for them. Although 12 other countries have passed laws to protect rays, Peru's may be the most important one yet. That's because there are more manta rays in the Pacific Ocean near Peru than in any other place in the world.
Giant manta rays are unusual — looking creatures. The giant, flat rays are typically about 4.5 meters wide and can grow up to 8 meters wide! "They're" sort of like giant flying carpets underwater, says Joshua Stewart of the Manta Trust, an organization that researches manta rays.
People catch rays for their meal. Overfishing is bad for any sea creature, but it's even worse for manta rays. Female manta rays usually have only one baby every two to five years. So every ray that's caught hurts the population in a big way. People who break Peru's new law can be fined or have their fishing licenses taken away. Even rays caught accidentally in fishing nets must be set free.
Earlier this year, the Manta Trust attached video cameras, called Crittercams, to manta rays off the west coast of Mexico. The footage(连续镜头)the cameras collect could help researchers predict where rays swim and when. The scientists could use the information to warn fishing boats to avoid these areas, helping reduce the number of accidentally caught rays.
Stewart says it's important to protect these unique creatures. "There's really no other animal that compares in size and that you can have interactions with in the wild.
1. What's a characteristic of manta rays?| A．They can fly like a bird. |
| B．They are usually of small size. |
| C．They are very friendly to people |
| D．They like swimming up and down. |
| A．They haven't their own home. |
| B．They only live in the Pacific Ocean. |
| C．Their number has dropped greatly. |
| D．Almost no female rays give birth. |
| A．protect them | B．look for more rays |
| C．make films about them | D．reduce their population |
| A．It makes no sense. | B．It is hard to follow. |
| C．It is really essential, | D．It needs improvement. |
8 . Italy's fashion capital is gray — not only because of the blocks of stone buildings，but also due to its often-gray sky, which traps pollution. But Milan now wants to change it.
The city has an ambitious plan to plant 3 million new trees by 2030 - a move that experts say could offer relief from the city's hot weather. Some projects have already contributed to environmental improvements. Architect Stefano Boeri’s Vertical Forest residential (居民的) tower, completed in 2014, aims to improve not only air quality but the quality of life for Milan residents. Boeri created a small island of greenery in the heart of Milan, filling every balcony with plants that absorb carbon dioxide.
“I think forestation is one of the best chances that we have today. It is one of the most effective ways we have to fight climate change, because everyone can plant trees, Boeri said.
Damiano Di Simine, a member of the environmental group Legambiente , said the green Milan project will lower temperatures in a city where the nighttime temperature can be 6 degrees Celsius higher than in the surrounding area. City show that Milan experiences 35 hot nights a year. Because the city lies close to the Alps, Milin gets very little wind to lower the city's temperatures. "Planting trees will help this," Di said.
The Vertical Forest has attracted more than 20 species of birds. And the shade provided by the 800 trees and 15,000 plants means that residents rarely have to put on air conditioning, even in hot summers. The Vertical Forest's total greenery- can absorb 30 metric tons of carbon dioxide every year. The presence of green trees has a very important effect on people's health and psychological state, as has already been proved.
1. What change does Milan plan to make?| A．Planting more trees. |
| B．Creating a new fashion style. |
| C．Pulling down more gray stone buildings. |
| D．Doing more surveys to study global wanning. |
| A．It costs a lot. |
| B．It is unpractical. |
| C．It fails to attract people's attention. |
| D．It is helpful to fight against climate change. |
| A．Doubtful. | B．Supportive. |
| C．Disappointed. | D．Unconcerned. |
| A．Specifics of the city's plan. |
| B．Challenges faced by the city. |
| C．The aim of the Vertical Forest project. |
| D．The positive effect of the Vertical Forest project. |
9 . Masks that helped save lives are proving a deadly danger for wildlife, with birds and sea creatures trapped in the shocking number of thrown-away facial coverings. Single-use masks have been found around pavements, waterways and beaches worldwide. Worn once, the thin protective materials can take hundreds of years to decompose. “Face masks aren't going away any time soon—but when we throw them away, these items can harm the environment and the animals,” Ashley Fruno of animal rights group PETA said.
In Britain, a gull was rescued by the RSPCA after its legs became tangled in the straps of a mask for up to a week. The animal welfare charity took it to a wildlife hospital for treatment before its release.
The biggest impact may be in the water. More than 1.5 billion masks made their way into the world's oceans last year, accounting for around 6,200 extra tonnes of ocean plastic pollution, according to environmental group Oceans Asia.
Conservationists in Brazil found one mask inside the stomach of a penguin after its body was washed up on a beach, while a dead pufferfish was discovered caught inside another off the coast of Miami. French campaigners found a dead crab trapped in a mask near the Mediterranean. Masks and gloves are “particularly problematic” for sea creatures, says George Leonard, chief scientist from NGO Ocean Conservancy. “When those plastics break down in the environment, they then enter the food chain and impact entire ecosystems.” he added.
There has been a shift towards greater use of reusable cloth masks as the pandemic has worn on, but many are still using the lighter single-use varieties. Campaigners have urged people to bin them properly and cut the straps to reduce the risk of animals becoming trapped. Oceans Asia has also called on governments to increase fines for littering and encourage the use of washable masks.
1. What's Paragraph 1 mainly about?| A．The problem of littering masks. | B．The long time to break down masks. |
| C．The threat of masks to wildlife. | D．The protective use of masks to people. |
| A．They gave first aid to the bird. | B．They released the bird at once. |
| C．They kept the bird for about a week. | D．They sent the bird to hospital. |
| A．By providing examples. | B．By giving explanations. |
| C．By making comparisons. | D．By analyzing causes. |
| A．Forbidding the use of single-use masks. | B．Wearing reusable cloth masks. |
| C．Cutting the masks up before throwing. | D．Increasing fines for binning masks. |
10 . Wildfires, producing lots of smoke seen obviously from space, are spreading in Sibetia.Greenland, Alaska, and Canada as a result of lightning and high temperatures. Although Arctic fires are common between May and October, the long time and large rang-involved make these fires unusual.Unfortunately, peat(泥炭) fires burn far longer than normal forest fires——for months, and sometimes even years.
Usually, dead plants and animals buried under the earth's surface change into coal over millions of years, under heat and pressure. However, sometimes the remains of plants pile up at the bottom of lakes and other water conditions. Here, as dead plants pile up on top of each other, they go through a slow process of decay (腐烂) due to lack of oxygen. The carbon that is trapped in these plants is turned into peat.
Peatlands refer to large areas of peat, many of which were formed after the Ice Age as a result of melting glaciers(冰/) or rising underground water levels. Peatlands are one of the largest natural carbon storehouses on the earth and contain over 550 billion tons of carbon. While peat is not used to produce electricity directly, it is processed, dried, and used as a fuel for heating and cooking in homes. Peatlands are also home to many species, provide drinking water, and minimize the risks of floods.
The Arctic fires have released around 50 million tons of carbon dioxide in June. In fact, more carbon dioxide was released in June than the combined amount from 2010 to 2018. Scientists are concerned that the Arctic fires may pump so much carbon dioxide into the atmosphere that we could reach a dangerous point in our earth's climate.
Unfortunately, Russian firefighters are unable to put out the fire in some parts that people can't reach of the Siberian Arctic. For now, the only hope is rain or snow which is expected only in October. These fires are also a wake-up call that we need to take some steps to solve global warming.
1. What is special about the peat fire?| A．It lasts a long time. | B．It occurs frequently. |
| C．It is easy to put out. | D．It does little harm. |
| A．How plants change into coal. | B．What makes plants decay. |
| C．How peat is formed. | D．What peat contains. |
| A．They were formed not a long time ago. |
| B．Large quantities of carbon are trapped by peatlands. |
| C．Peatlands can be used to produce electricity directly. |
| D．Few animals can survive in peatlands for lack of oxygen. |
| A．Arctic Fires Under Control | B．Peatlands Reduce Floods |
| C．Global Warming Is Harmful | D．Fires Burn in the Arctic |
