Nearly 40 years ago, Peter Harrison, a marine ecologist witnessed the first recorded large-scale coral bleaching(珊瑚白化)event. Diving in the Great Barrier Reef(大堡礁), he was shocked by the scene before him. "The reef was made up of healthy corals and badly bleached white corals, like the beginnings of a ghost city," he says. Just months before, the same site was filled with colorful tropical life.
"Many of the hundreds of corals that I'd carefully tagged and monitored finally died," he says. "It was shocking and made me aware of just how weak these corals really are.”
Coral exists together with photosynthetic algae(藻类), which live in its tissues and provide essential nutrition(and coloration). But high temperatures and other stresses can turn algae poisonous. When this occurs, the algae may die or be removed by the coral, a process known as bleaching because the coral's clear tissue and white calcium carbonate skeleton(碳酸钙骨骼)are exposed. If the coral can't reestablish its link with algae, it will starve or become ill.
The widespread destruction Harrison saw in 1982 was repeated on many other Pacific Ocean reefs that year and the next. In 1997 and 1998 the phenomenon went global, killing some 16 percent of the world's corals. With rising temperatures, pollution, disease, increased ocean acidity, invasive species, and other dangers, Harrison's ghost cities are expanding
Scientists suppose that about four decades ago severe bleaching occurred roughly every 25 years, giving corals time to recover. But bleaching events are coming faster now—about every six years—and in some places soon they could begin to happen annually.
"The absolute key is dealing with global warming," says marine biologist Terry Hughes. "No matter how much we clean up the water, the reefs will die." In 2016, a record-hot year in a string of them, 91 percent of the reefs that consist of the Great Barrier Reef bleached.
1. Peter Harrison was shocked when diving in the Great Barrier Reef, because___________.A.the reefs were made up of precious corals | B.the corals were ruined badly and quickly |
C.he found a ghost city with tropical life | D.he saw the corals he had tagged before |
A.the causes of coral bleaching | B.the weakness of corals and algae |
C.the elements that make algae die | D.the process of building a link with algae |
A.global warming | B.the polluted ocean | C.the white corals | D.invasive species |
A.With algae living in its tissues, coral's white skeleton is exposed. |
B.Solving global warming is the real solution to coral bleaching. |
C.The reefs die because the water hasn't been cleaned thoroughly |
D.The severest coral bleaching occurred about four decades ago. |
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【推荐1】The Intergovernmental Panel on Climate Change (IPCC) released a report. It stated that the world is quickly running out of time to keep global warming below 1.5 degrees Celsius, the level widely agreed to be the conservative, safety-first goal to prevent serious climate harm. To get there, the world would have to cut current emissions (排放物) by 45 percent by 2030. That sounds absurdly unlikely.
But before we give in to despair, we should remember that the technology to address climate change is going along at high speed. The largest source of US carbon emissions is transportation, and a Green New Deal program for motor vehicles would be quite straightforward.
The reason is simple: With some subsidies (补贴), electric cars and buses are cost- competitive with fossil-fuel vehicles. Electric buses have gone into the market at the greatest speed, because they are a logical choice for electrification. At the end of 2018, electric vehicles were displacing about 280,000 barrels of oil demand per day. That’s more than the whole consumption of Greece.
And 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 basic systems necessary to recharge electric vehicles already exist. People often tend to assume that we would need to replace every gas station, but virtually 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, rails, shipping, and so on to fully decarbonize (脱碳) the transportation sector. It will be considerably more difficult than simply rooting out fossil fuel vehicles from the market.
But greening America’s vehicles would be straightforward, relatively cheap, and a huge step forward on climate. The politics of climate change are so fearful that despair can seem logical, but the first step in achieving a tough goal is the firm belief that it can be done. And this particular step wouldn’t even be that tough.
1. What can we infer from the IPCC’s report?A.The world is suffering serious climate harm. |
B.Global warming is growing out of our control. |
C.We are too conservative to deal with global warming. |
D.Cutting emissions is the easiest way to stop climate change. |
A.By running at the greatest speed. |
B.By changing the way of transportation. |
C.By making consumers have logical choices. |
D.By getting financial support from governments. |
A.They aren’t so efficient in reducing emissions. |
B.There’s still much room for designing new ones. |
C.There aren’t enough fast charging stations for them. |
D.Home electrical connection can be used for charging them. |
A.Doubtful. | B.Critical. | C.Positive. | D.Uncaring. |
【推荐2】Fashion designers are always looking for new materials to work with. Lately, it’s all about environment-friendly materials -- recycled tires, mushrooms, even pineapple fibers! What if you want such a pair of shoes? Thaely is here to help.
This sneaker brand out of Dubai wants to fight the growing problem of plastic pollution. Led by 23-year-old Indian businessman Ashay Bhave, they may have found a winning approach: making shoes out of plastic grocery bags. “Thaely” means “plastic bag” in the Hindi language.
“I was looking to create footwear that is cost-effective and safe for the environment,” Bhave said in an interview with a newspaper. “I needed to come up with something that uses recycled plastic without creating any more plastic waste. ”Plastic bags were the perfect solution. He said five trillion plastic bags are used around the world each year. “I was motivated to find a solution to this problem,” Bhave said.
That solution was the fiber called ThaelyTex. Made entirely from plastic bags, the material looks and feels like leather. That sounds promising. Better yet, the production process requires no additional chemicals and produces no poisonous by-products. The result is a smart-looking pair of white low-top sneakers.
Bhave wouldn’t expose the full process for making ThaelyTex, but he said that each pair of shoes was made from up to 15 plastic bags and 22 plastic bottles. Where do they get the materials? Bhave told Elle that was the hardest part. “The biggest challenge we faced was right at the first step of acquiring the plastic bags. ”
Finally, they got help from TrioTap Technologies, a waste management plant. Bhave said they offered to collect the bags and also process them into ThaelyTex.
So far, it seems like things are falling into place. There are already hundreds of pre-orders in place. It sounds like they have some plans for the future. “We have a few more colors coming up,” said Bhave. They also plan to put out a high-top model and bring in a line of clothing. Let’s hope their growth is also friendly to the environment.
1. Why did Bhave choose to make shoes out of plastic bags?A.To set a new footwear trend. |
B.To test new materials for footwear. |
C.To reduce the use of plastic bags in his home country. |
D.To use recycled plastic in an environment-friendly way. |
A.Having a few more colors for Thaely. | B.Processing plastic bags into ThaelyTex. |
C.Collecting enough production materials | D.Dealing with many poisonous by-products |
A.produce | B.conserve |
C.provide | D.broadcast |
A.Bhave: a promising young man |
B.Thaely: killer of waste plastic bags |
C.ThaelyTex: material out of plastic bags |
D.TrioTap Technologies: a waste management plant |
【推荐3】Chocolate could soon be a thing of the past, after scientists warned that the cacao plant, from which chocolate is made, could be extinct within 32 years.
Over half of the world’s chocolate comes from just two countries in West Africa—Cote d’Ivoire and Ghana—where the temperature, rain, and humidity provide the perfect conditions for cacao to grow. But the threat of rising temperatures over the next three decades caused by climate change, is expected to result in a loss of water from the ground, which scientists say could upset this balance.
According to the related data, a temperature rise of just 2.1℃ could spell an end for the chocolate industry worldwide by 2050. Farmers in the region are already considering moving cacao production areas thousands of feet uphill into mountainous area—much of which is currently preserved for wildlife. But a move of this scale could destroy ecosystems that are already under threat from illegal farming and deforestation.
Part of the problem, according to Doug Hawkins, is that cacao farming methods have not changed for hundreds of years. “Unlike other tree crops that have benefited from the development of modern, high yielding strains and crop management techniques to realize their genetic potential, more than 90% of the global cocoa crop is produced by small farms with unimproved planting material,” he said. “It means that we could be facing a chocolate decrease of 100,000 tons a year in the next few years.”
Now scientists at the University of California at Berkeley have teamed up with American candy company Mars to keep chocolate on the menu. Using the controversial(有争议的) gene-editing technology known as CRISPR they are trying to develop a type of the cacao plant capable of surviving in dryer, warmer climates. If the team’s work on the cacao plant is successful, it could remove the need for farmers in West Africa to relocate to higher ground, and perhaps even allow cacao to be grown elsewhere in the world.
1. What do we know about chocolate from the text?A.Chocolate will disappear from the menu 30 years later. |
B.Chocolate is mainly produced by African countries. |
C.Chocolate will not be produced by 2050 because of climate change. |
D.A new type of chocolate will be produced with the help of CRISPR. |
A.The damaged ecosystem. |
B.Water shortage caused by climate change. |
C.The threat from illegal farming. |
D.The changeable farming method. |
A.Objective. | B.Unconcerned. | C.Supportive. | D.Negative. |
【推荐1】A new study finds that less than seven percent of the adult population in the US have what health experts consider good cardiometabolic (心脏代谢) health.
Using information on roughly 55,000 people over the age of 20, the results show just 6.8 percent of American adults reached optimal (最佳的) levels of health in 2018. Moreover, the study found American health has been in sharp decline over the last 20 years. In 1999, one in three adults had a healthy weight. By 2018, that number fell to just one in four Americans. At the same time, three in five people were free of diabetes in 1999. By 2018, however, more than six in ten adults had the condition!
“These numbers are striking. It’s deeply problematic that in the United States, fewer than 1 in 15 adults have optimal cardiometabolic health,” says Meghan O’Hearn, one of the researchers from Tufts University. “We need a complete overhaul (革新) of our healthcare system, food system, and living conditions, because this is a crisis for everyone.”
Instead of just looking for signs of disease, the team focused their study on the signs of good, moderate, and poor cardiometabolic health. “Disease is not the only problem,” O’Hearn explains. “We don’t just want to be free of disease. We want to achieve optimal health and well-being.”
Researchers also found large health gaps between US adults of different genders, ages, and education levels. Specifically, the study found Americans with less education were half as likely to be in peak cardiometabolic health.
O’Hearn adds, “Identifying these individuals and addressing their health conditions and lifestyle early is critical to reducing growing healthcare burdens. Its impacts on national healthcare spending and the financial health of the entire economy are enormous. And these conditions are largely preventable. We have the public health and clinical interventions and policies to be able to address these problems.”
1. What percentage of American adults had optimal cardiometabolic health in 2018?A.Over 7 percent. | B.Just 6.8 percent. |
C.Around 33 percent. | D.About 60 percent. |
A.They’re unreal. | B.They’re acceptable. |
C.They’re expected. | D.They’re shocking. |
A.To find the big age gap. | B.To help people keep fit. |
C.To develop new drugs. | D.To earn lots of profits. |
A.Joint effort is needed to improve public health. |
B.Economic growth affects personal health condition. |
C.America saw a slow decrease in healthcare costs. |
D.Rich people tend to suffer from health problems. |
【推荐2】Enjoy the Challenge of a New Term
The new term is finally here, which means, of course, it’s time to re turn to school.
For many students across China, that also means having to leave home for the next several months and move into a school dormitory.
Being away from our family for a long time, however, often leads to homesickness, a feeling that most students have experienced at some point.
A study by the UK’s National Union of Students found that up to 70 percent of UK students living away from home experience homesickness within their first few weeks of being away.
But homesickness isn’t just a feeling of sadness that happens in our mind; it can also affect us physically. “You feel homesickness in your stomach-it’s an unease in which you feel uncomfortable, nervous, stressed because you’re in a place or situation that’s not familiar,” Joshua Klapow, a professor of public health at the University of Alabama, US, told HuffPost.
According to Klapow, the body reacts physically when it’s placed in an unknown situation such as being separated from one’s familiar surroundings for a long time.
“It’s an evoutionary(进化的) thing that makes us protect ourselves from danger when something is unknown,” he told the HuffPast.
“When we think about home, we know that the sense of unknown is not happening there, so we want to return.”
So, how can we overcome these physical reactions?
Ruth Hardy of the Guardian offered advice for students who are feeling the effects of being away from the safety of home.
“Try and establish routines(常规) quickly. This can make your new environment feel more stable and will hopefully make you feel more settled,” she wrote.
Making friends with others who are in your situation is also a great way to feel less homesick, according to Hardy.
The most important thing to remember, however, is that homesickness is completely normal and is nothing to be ashamed of.
And once it’s gone, you’re free to enjoy the adventures and challenges of a brand new school year.
1. The study by the UK’s National Union of Students is mentioned to______.A.show how homesickness causes harm to students |
B.prove it common for students to feel homesick |
C.introduce some causes of homesickness |
D.show how all young people are troubled by homesickness |
A.It has a physical influence on our body. |
B.It usually disappears after a few weeks. |
C.It’s only a feeling in our mind. |
D.It always happens once we visit an unfamiliar place. |
A.It shows people the importance of their family. |
B.It drives people to get used to changes. |
C.It encourages people to express their feelings. |
D.It keeps people away from possible dangers. |
【推荐3】A latest study on people who eat red meat has found they have higher risks of heart disease and early death. The finding goes against other recent research that suggested removing meat from one's diet has few health benefits. The two opposing findings can make it difficult for people to make sense of what can seem to be conflicting messages on food.
Duane Mellor, a dietician at Aston University, and other researchers say that after examining research on the subject, moderation may be the best way forward. “In this case, eating a certain amount of meat, including red meat, is likely to be safe,” Mellor said. “However, in the interest of health, reducing meat intake to the recommended less than 70 grams per day would be sensible.”
A researcher with ties to the meat industry published a report on the subject in 2019, saying that people should not reduce the amount of red meat they eat. Some experts criticized the findings because they were in conflict with dietary advice from international agencies.
The latest study found that eating two servings a week of red meat or processed meat was linked to a 3% to 7% higher risk of heart disease and also a 3% higher risk of all causes of death. Norrina Allen, a co-leader of the latest study, said the health risk is small but people should try to change their diet. “It's a small difference, but it's worth trying to reduce red meat and processed meat.” She added that eating red meat is also regularly “linked to other health problems like cancer.”
The World Cancer Research Fund says red and processed meat may cause cancer. It recommends eating red meat with an upper limit of 500 grams cooked weight per week-and “little, if any” processed meat. They said on average, adults should reduce the amount of meat they eat by 50% and they should eat twice as much nuts, fruits, vegetables and beans.
1. What does the latest study suggest?A.People should not cut down on the amount of red meat they eat. |
B.People should remove meat from their diet for the benefit of health. |
C.Eating red meat is linked to higher risks of heart disease and early death. |
D.Eating two servings a week of red meat or processed meat has no health risks. |
A.Doing research by oneself. |
B.Following one's own heart. |
C.Avoiding conflicts with others. |
D.Staying within reasonable limits. |
A.It will help improve our eating habit. |
B.It is in conflict with her former study. |
C.It has offered two regular cures for cancer. |
D.It makes no difference to the meat industry. |
A.Some tips on cooking. |
B.Advice on a healthy diet. |
C.Research on the cause of cancer. |
D.Ties between meat and vegetables. |