As warming continues, scientists warn the oxygen content of oceans across the planet could be more and more reduced, with serious consequences for the future of fish and other sea life.
Global warming is expected to reduce the mixing of the ocean by making surface seawater lighter. That's because in a warmer world we can expect more rainfall and more melting of glaciers, icebergs, and ice sheets.
A low-oxygen ocean may become an inescapable feature of our planet. A team of Danish researchers wondered how long oxygen levels would drop if we could somehow reduce our carbon dioxide emissions to zero by 2100. They determined that over the next few thousand years oxygen levels would continue to fall, until they declined by 30 percent. The oxygen would slowly return to the oceans, but even 100,000 years from now they will not have fully recovered.
A.The entire ocean gets its oxygen from the surface. |
B.It's not known why the oxygen level of oceans has reduced. |
C.Scientists point to two reasons to expect a drop in ocean oxygen. |
D.Fresh water's inpouring will make the water at the ocean's surface lighter. |
E.Global warming has caused the reduction of the oxygen content of oceans worldwide. |
F.If they are rights, we have every reason to worry about the major effect it has on sea life. |
G.The light surface water will be less likely to sink so the deep ocean will get less oxygen. |
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【推荐1】A team of psychologists led by Dr. Karen McComb at the University of Sussex in the UK have discovered an effective way for humans to communicate with cats through slow blinking (眨眼睛), similar to how cats interact with each other.
Dr. McComb and her team conducted two experiments to study this phenomenon. In the first study, owners were instructed by researchers Tasmin Humphrey and Andrew Wood to slowly blink at their cats from a distance while being recorded. Humphrey and Wood found the cats were more likely to respond with slow blinking of their own compared to when no interaction took place.
To follow up on these findings, McComb, Humphrey, and Wood designed a second experiment without considering the exsisting relationship between humans and cats. Researchers, including McComb, performed the same slow blinking action. Like in the first experiment, the cats in this study also responded more favorably to slow blinking by returning the gesture and more readily approaching an extended hand, according to Humphrey’s analysis.
The slow blink expression involves partially closing the eyes briefly, copying a relaxed, friendly facial expression in humans. McComb notes that for cats, it appears to signal good intentions as constant staring could be seen as threatening. Wood says that cats may have developed this language to acknowledge humans who react positively to the signal. Being able to effectively communicate acceptance in this subtle cat way seems to strengthen the bond between cats and their owners, McComb adds.
McComb, Humphrey and Wood hope their findings can provide insight into cat behavior and thinking. They also aim to apply this knowledge of cross-species communication to evaluate cat health in various places like veterinary (兽医的) clinics and shelters, according to Humphrey. A deeper understanding of how cats interpret and respond to humans can improve our ability to properly care for household and outdoor cat populations, McComb concludes.
1. How was the second experiment different from the first one?A.It recorded the interactive behavior of cats. |
B.It required cat owners to blink from a distance. |
C.It studied how cats communicate with each other. |
D.It focused on how cats react to strangers’ slow blinking. |
A.To attract their owners’ attention. |
B.To show friendliness to other animals. |
C.To respond to humans’ positive reactions. |
D.To send out a signal for help to their partners. |
A.Improving cat behavior and habits. |
B.Assessing health conditions of cats. |
C.Developing ways to treat cats’ diseases. |
D.Helping cat owners train their cats quickly. |
A.Humans can communicate with cats by blinking slowly. |
B.Extending hands to cats can strengthen the bond with them. |
C.Cats respond favorably to humans’ friendly facial expressions. |
D.Understanding cat signals improves humans’ ability to care for them. |
【推荐2】Autism Spectrum Disorder(ASD)(孤独症)is a disability that can cause serious social,communication and behavioral problems.There is often nothing about how people with ASD look that makes them different from other people,but people with ASD may communicate,interact,behave,and learn in ways that are different from most other people.The learning,thinking,and problem-solving abilities of people with ASD can range from pretty good to extremely bad.Some people with ASD need a lot of help in their daily lives;others need less.
People with ASD often have problems with social,emotional,and communication skills.They might repeat certain behaviors and might not want change in their daily activities.Many people with ASD may also have difficulties learning,paying attention,or reacting to things.Signs of ASD begin during early childhood and probably last throughout a person's life.
Diagnosing(诊断)ASD can be difficult since there is no medical test,like a blood test,to assess the disorders.Doctors look at the child's behavior and development to make a judgement.ASD can sometimes be diagnosed at 18 months or younger.By age 2,an experienced doctor can be considered very reliable in diagnosing ASD.However,many children may not see a doctor until much older.
There is currently no cure for ASD.However,research shows that early treatment services can improve a child's development.Early treatment services help children from birth to 3 years old(36 months)learn important skills.Therefore,it is important to talk to your child's doctor as soon as possible if you think your child has ASD or other developmental problems.
We do not know all of the causes of ASD.However,most scientists agree that genes are one of the highest risk factors that can make a person more likely to develop ASD.
If you think your child might have ASD or you think there could be a problem with the way your child plays,learns,speaks,or acts,contact your child's doctor,and share your concerns.If you're not sure who to contact,call the Early Childhood Technical Assistance Center(ECTA)at 919-962-2001.Or visit the ECTA website:https://ectacenter.org.
1. Which of the following behaviors may NOT belong to the children or adults with ASD?A.Repeating actions over and over again. |
B.Having trouble expressing their needs. |
C.Avoiding eye contact and want to be alone. |
D.Being happy to make changes. |
A.The earlier an ASD kid is diagnosed,the better it is for his(her)treatment. |
B.Doctors simply have no way to diagnose an ASD kid at all. |
C.Doctors can diagnose ASD by blood testing. |
D.Doctors can diagnose ASD with the help of machines. |
A.Someone who prefers to talk a lot in daily life. |
B.Someone who has got an ASD brother. |
C.Someone who wants to hug you in public. |
D.Someone who sings in a strange voice. |
A.A guidebook for new parents. |
B.Education section of a newspaper. |
C.A student's diary. |
D.A medical magazine. |
【推荐3】Feeling overwhelmed by your to-do list can certainly make you unhappy, but new research suggests that more free time might not be the magic medicine many of us dream it could be.
In a new study, researchers found that people with more free time generally had higher levels of subjective well-being, but only up to a point.
People who had up to two hours of free time a day generally reported they felt better than those who’d had less time. But people who had five or more hours of free time a day generally said they felt worse. So ultimately the free-time “sweet spot” might be two to three hours per day, the findings suggest.
Part of finding the “sweet spot” has to do with how people spend the extra time they have. The researchers conducted several smaller online experiments. In one they asked participants to imagine having 3½ to seven free hours per day. They were asked to imagine spending that time doing “productive” things (like exercising) or to imagine doing “unproductive” activities (like watching TV). Study participants believed their well-being would suffer if they had a lot of free time during the day, but only if they used it unproductively. In other words, how people use their free time matters.
Of course, what feels “productive” is up to you. If watching two hours of Real Housewives in your free time increases your happiness, you should do that. And even more traditionally productive or purposeful activities can be easy and fun. Engaging in a bit of low-key cardio, like walking, can help burn stress. Free-time activities like reading, cooking or gaming are also known to put people in a state of flow.
In cases when people do find themselves with huge amounts of free time, such as retirement or having left a job,” Sharif said, “our results suggest these individuals would benefit from spending their newfound time with purpose.”
1. According to the study, how many hours of free time brings the best feelings?A.3 to 7 hours. | B.5 hours or more. | C.Up to 2 hours. | D.2 or 3 hours. |
A.The busier, the happier. |
B.The more free time, the better. |
C.Purposeful activities increase happiness. |
D.Retirement makes people depressed and unhappy. |
A.Getting stuck in silence. | B.Having a poor-quality sleep. |
C.Struggling with a dull book. | D.Enjoying classic music. |
A.To make a new schedule. | B.To do more housework. |
C.To watch more TV. | D.To find a new job. |
A.Stories. | B.Life. | C.Science. | D.Sports. |
【推荐1】In 2014, Xu Yitang, a Beijing native who had been studying Peking Opera since childhood, went with friends for a birthday celebration to Beijing Zoo. Little did he know that a chance encounter at the aquarium there would excite a lifelong passion. As Xu Yitang stared at corals bathed in tank’s light, a sense of wonder crowded into his mind. Lost in the beauty and mystery of the creatures, he spent the entire afternoon in front of it. After that, he began to frequent the local market to learn about coral farming from merchants who sell ornamental plants, fish and corals. He also searched for information on relevant forums online. Before long, he had set up a small fish tank at home and started cultivating a coral.
Nowadays, Xu Yitang who has moved to the tropical island of South China’s Hainan province, works for a Sanya-based tropical biological laboratory belonging to the Chinese Academy of Sciences. Each day, he spends several hours diving deep under the waves to observe and document the growth and development of the creatures that captured his heart all those years ago. Nicknamed “coral man”, he is actively engaged on such social media platforms as Sina Weibo, where he regularly shares visually beautiful photos and entertaining videos of corals. He aims to encourage individuals to take action in protecting coral reefs and the oceans as a whole from the destructive impact of climate change and human activities.
Unfortunately, with the strengthening of the greenhouse effect, rising sea temperatures have led to coral bleaching (白化) and decay. A coral reef’s beautiful colors come from the symbiotic algae (共生藻类) zooxanthellae that provide more than 90 percent of the energy through photosynthesis (光合作用). Coral bleaching occurs when coral expels the algae and dies due to the lack of nutrients.
In the laboratory, he would film educational videos to raise awareness and knowledge about corals, so that people can learn how to protect them effectively.
1. What changed Xu Yitang’s career choice?A.Frequenting the local market. |
B.Setting up a small fish tank at home. |
C.Having an encounter at the aquarium. |
D.Observing coral growth and development. |
A.Xu is a diver in the lab. |
B.Xu is a coral conservationist. |
C.Xu spends few hours on his work every day. |
D.Xu shares his videos for corals through social media platforms. |
A.Rising sea temperatures. | B.Lots of nutrients in the water. |
C.Coral farming practices. | D.Lack of sunlight in deep waters. |
A.Critical. | B.Indifferent. | C.Objective. | D.Enthusiastic. |
【推荐2】Australia recently declared the koala an endangered species in Queensland, the Australian Capital Territory, and New South Wales (NSW) because of its obvious population decline. In the state of NSW, koala conservation has become a key topic of discussion in the lead-up to the 25 March state election. However, the debate has focused on the expansion of protected areas and ignored the importance of koala conservation on private lands.
The major cause of the koala’s decline—in addition to climate change, wildfires, disease, and encounters with vehicles and dogs—is the loss and degradation(退化)of suitable habitat. In response, the NSW Government has expanded publicly protected areas in the state. Over the past 20 years—about three koala generations—NSW has officially confirmed an additional 1.5 million hectares(公顷)of protected land, some of which is high-quality koala habitat.
However, across Queensland, the Australian Capital Territory and NSW, 77% of the koala’s range is located on land that is owned or rented by private citizens or businesses, where degradation continues. Between 2003 and 2020, agriculture, forestry and infrastructure(基础设施)development have led to the act of cutting down or burning the trees within 760,500 hectare in NSW, including in regions such as the Cumberland Plain and Liverpool Plains, where koalas are known to live. Such development has reduced the gains made through new protected areas.
The current NSW Koala Strategy adopts a free approach without any restrictions, which leaves private landowners, renters and industry have the power to decide what should be done in much of koala habitat conservation.
An effective koala conservation strategy must include conservation measures in private protected areas, such as payments for ecosystem services, in addition to publicly protected areas. In other words, post-election agendas must strengthen protection of koala habitats on private lands.
1. What did the discussion before the state election fail to notice?A.The voice of local citizens. | B.The expansion of protected areas. |
C.The decrease of koala population. | D.The koala conservation on private lands. |
A.the attack of diseases | B.the spreading wildfires |
C.the worsening of living environment | D.the constant threats from climate change |
A.Add some background information. | B.Summarize the previous paragraphs. |
C.Introduce a new topic for discussion. | D.Offer some advice for the government. |
A.Supportive. | B.Disapproving. |
C.Tolerant. | D.Unclear. |
【推荐3】Ways to save the Earth as a family
These days the news about the planet can be overwhelming for kids and their parents. Actually, personal actions can make a difference.
UNPLUG
Don't worry—we don't mean taking a break from your phone. We’re talking about the charger. Chargers that remain plugged into the wall can suck energy even when the device is turned off. Ask your kids to remind you to unplug chargers when they’re not in use, as well as switch off power plugs for TVs and lamps.
FRESH FRUIT
Buying seasonal, local food cuts down on the energy needed to grow and transport it. Before taking your children to the grocery store, ask them to look for fruits and vegetables in season.
SAFE SOUVENIRS
Avoid souvenirs or other things made from animal parts like scales, teeth, feathers, seashells, and so on. Instead, take your kids to local markets where you can meet the artists and search for something made of materials like used cans, or magazine paper.
KID SCIENTISTS
Instantly transform your kids into scientists by signing up for a citizen science project that identifies animals. Just taking a photo of an animal and uploading it to a site like iNaturalist can help biologists learn how the animal is adapting to a changing world.
It's true that sweeping collective action is needed to control climate change, but small adjustments by people help too. Plus, by taking action to protect the planet, you can help your children feel empowered in the face of these global problems. Start with these tips to get the whole family involved in protecting the Earth.
1. Which of the following can help save electricity at home?A.UNPLUG. | B.FRESH FRUIT. | C.SAFE SOUVENIRS. | D.KID SCIENTISTS |
A.Hats decorated with beautiful bird feathers. | B.Necklaces with seashells looking attractive. |
C.Shopping bags made from some old clothes | D.Any artist's works from the local markets. |
A.It enriches the website by adding more pictures. |
B.It encourages kids to sign up for a science project. |
C.It offers kids more chances to identify animals. |
D.It can help scientists conduct scientific research |