Alaska’s Yukon River has faced major salmon shortages in recent years. Officials say record-high temperatures last year killed most salmon in the 3,200-kilometer river before the fish were able to reproduce. The losses led Alaska to stop their salmon harvests in 2021 to make sure that enough fish survived to reproduce for another year.
The poor salmon harvests caused major financial losses to private fishing companies in the area. The die-offs also hurt native communities, which traditionally store the fish as a year-round food supply.
Last month, the U.S. Department of Commerce declared a disaster for Yukon River fishing for 2020 and 2021, making aid money available. Alaska has sent emergency fish shipments to areas affected by the salmon shortages.
Scientists have mostly blamed the problems on a series of heat waves in the Bering Sea and North Pacific Ocean from 2014 to 2019. The warm ocean waters affected salmon’s living in the sea before they returned to lay eggs.
Climate change may also be affecting what the salmon are eating. Fishing experts say young salmon are likely filling up on nutrient-poor food because warmer waters drive away healthier organisms (有机物) they normally feed on. “In my opinion, the salmon are starving with climate change,” said Brooke Woods in the Yukon River Inter-Tribal Fish Commission.
The effects of climate change on freshwater environments have also been studied. Vanessa von Biela is a biologist who looked at the rivers, streams and lakes where salmon live. Her team found that Chinook salmon show heat stress at temperatures above 18℃. They start dying above 20℃. In 2019, temperatures on the Alaskan side were above 18℃ for 44 straight days, a recent study found.
The effects of warming waters can be reduced by climate-driven glacier (冰川) runoff, which brings cooler water into rivers and streams. But scientists still expect salmon to begin slowly moving to new areas within Alaska. “Salmon will find a way,” said Biela. “but it’s going to be hard for communities in places where there might not be salmon anymore.”
1. What do the locals rely on salmon for?A.Food supply. | B.Scientific study. | C.Green tourism. | D.Water improvement. |
A.Financial losses. | B.Relief funds. | C.Economic growth. | D.Fast delivery. |
A.No healthy organisms are left there. | B.Salmon there lose the ability to lay eggs. |
C.Salmon there go short of nutritious food. | D.The temperature remains above 18℃ till now. |
A.Measures to protect salmon are effective. | B.Salmon will not find a way out of the crisis. |
C.The amount of salmon will increase greatly. | D.Salmon are likely to leave the river for survival. |
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【推荐1】Based on new analysis, we are rapidly approaching major climate change and the effects on society and the environment could be quite severe. Geographers predict that within the next eighty years, current world climate zones could shift and some could completely disappear. Polar regions will get colder while tropical regions will get even hotter, forcing animals to migrate (迁徙) north.
Climate changes like these could lead to the spread of diseases. Tropical storms and hurricanes will not only increase but may also become more intense. If the changes come too quickly, animal and plant species may not be able to adapt fast enough and could disappear.
According to Science Daily, a new study predicts that by the year 2100, many of today’s familiar climates will be replaced by climates unknown in today’s world. It is urgent that we reduce the risks of these far-reaching consequences for the whole world. The planet itself has been showing signs of change. In 2004, a serious tsunami created by a major earthquake killed thousands in Sumatra and in 2008, thousands died in China because of another severe earthquake. Egypt was hit in 2009 with a major earthquake and Haiti was devastated in 2010 by yet another massive earthquake.
Within just the last few months, new reports from around the world have been coming in and most agree that our climate situation is much worse than previously thought. At this point, it doesn’t matter what is causing it, but rather, what can be done about it. What’s more, our world is getting more and more unstable every year. There is war and threat of war everywhere. Natural disasters are becoming more frequent and serious.
However, other planets are experiencing global warming as well as our own and some scientists believe there may be some connection between this. No one knows anything for sure at this point because there is simply not enough data.
1. What is the major function of paragraph 1?A.To arouse the reader’s concern. |
B.To introduce the theme of the whole passage. |
C.To summarize the whole passage. |
D.To state how climate changes. |
A.To show major changes are taking place on the planet. |
B.To remind people to prevent future earthquakes. |
C.To show the damage earthquakes caused. |
D.To tell us more earthquakes will happen in the future. |
A.Animal and plant species may not be able to adapt fast enough and could disappear. |
B.It could lead to the spread of diseases. |
C.Current world climate zones could shift and completely disappear. |
D.Natural disasters are becoming more frequent and serious. |
A.Animals and plants won’t die out as long as climate changes slowly. |
B.There’s enough data for us to predict the future of climate change. |
C.The world is getting more unstable because of animal migration. |
D.The earth is not the only planet that is experiencing climate change. |
【推荐2】The best time to try to fight global warming is now! Any action that reduces water and energy consumption and the build-up of harmful gases in our atmosphere, helps to minimize the effects of global warming. Simple ideas that you can easily put into practice are as follows.
Turn off devices (设备) that are not in use.
Walk or cycle as much as possible. Not only are these great ways to get some exercise, but they are the least polluting means of transport. For short distances, walking and cycling should really be your first choice. Nowadays, there are many shared bikes available.
Use public transport or car pool (拼车). If you need to travel longer distances, public transport is greenest.
A.Treat water as something precious. |
B.Learn something about water waste. |
C.Electronic devices are around the house these days. |
D.That means you don t even have to own one to get around. |
E.There are many devices that are good for the environment. |
F.You can try to find plenty of ideas for traditional games and toys. |
G.Taking the bus or subway is better than getting in your car and driving. |
【推荐3】The South Pole has been warming at more than three times the global average over the past 30 years, according to research led by Ohio University professor Ryan Fogt, and Kyle Clem, who is a current postdoctoral research fellow in climate science. According to the study, this warming period was mainly driven by natural tropical (热带的) climate variability and was likely strengthened by increases in greenhouse gases.
Clem and his team analyzed weather station data at the South Pole, as well as climate models to examine the warming in the Antarctic interior (内陆). They found that between 1989 and 2018, the South Pole had warmed by about 1. 8℃ over the past 30 years at a rate of +0. 6℃ per decade—three times the global average.
The study also found that the strong warming over the Antarctic interior in the last 30 years was mainly driven by the tropics, especially warm ocean temperatures in the western tropical Pacific Ocean that changed the winds in the South Atlantic near Antarctica and increased the delivery of warm air to the South Pole. They suggest these atmospheric changes along Antarctica's coast are an important mechanism driving climate anomalies (异常事物) in its interior.
Clem and Fogt argue that these warming trends were unlikely the result of natural climate change alone, stressing the effects of added warming related to human activities on top of the large tropical climate signal on Antarctic climate have worked together to make this one of the strongest warming trends worldwide.
“From the very beginning, Kyle and I worked very well together and were able to accomplish more as a team than we were individually,” Fogt said. “We have published every year together since 2013, with one of our continuing collaborations being the annual State of the Climate reports. Our work on this project together each year ultimately led to this publication documenting the warming at the South Pole. However, most importantly for my family and me, apart from being a fantastic scientist and collaborator, Kyle is also considered as one of our closest friends.”
1. What is the major cause of the South Pole's warming according to the research?A.The weather station. | B.Lack of winds. |
C.Increases of greenhouse gases. | D.Natural tropical climate change. |
A.The tropical climate signals in the Antarctic interior. |
B.The effect of human activities on the warming trends. |
C.The detailed explanation for the South Pole's warming. |
D.The unpleasant consequences of natural climate change. |
A.Cooperation is valued in scientific research. |
B.Getting science paper published is difficult. |
C.Friendship is more important than science. |
D.Family support plays a key role in science. |
A.A chemistry textbook. | B.A science magazine. |
C.A travel brochure. | D.A science novel. |
【推荐1】As any cat owner will tell you, talking to your cat is totally normal. And even though feline(猫) friends may seem distant to these adoring talks, a new study in Animal Cognition suggests they are really listening.
Researchers in France exposed house cats to recordings of their owner or a stranger saying phrases in cat-or human-directed speech. Like baby talk, cat-directed speech is typically higher pitched with short, repetitive phrases. The team found that felines tended to react to their owner speaking in cat-directed speech—but not to their owner speaking in adult tones or to a stranger using either adult-or cat-directed speech.
Previous research had shown similar findings in dogs, but much less is known when it comes to cats. “Some people still consider cats independent—you cannot have a real relationship with cats,” says lead study author Charlotte Mouzon, a cat behaviorist at the University of Paris Nanterre. Some people might be embarrassed about using special vocalizations for cats, she says, but this research shows “people shouldn’t be ashamed.”
Mouzon and her team recorded 16 cat owners saying such as “Do you want to play?” or “Do you want a treat?” in cat-and human-directed speech. Then they filmed each cat before, during and after playing it a series of recordings of its owner and other owners’ speech. The researchers used software to rate the cats’ reactions from multiple dimensions, making the result more convincing.
“Although cats have a reputation for ignoring their owners, a growing body of research indicates that cats pay close attention to humans,” says Kristyn Vitale, a cat behavior scientist at Unity College in Maine, who was not involved in the study. “Cats can learn that specific speech has certain meanings.” But she notes the study is too small and that future work is needed to expand the research to other cat populations.
1. According to paragraph 2, what do house cats respond obviously to?A.The owner’s cat-directed tone. | B.A stranger’s human-directed talks. |
C.A stranger’s cat-directed recordings. | D.The owner’s human-directed speech. |
A.Strategies. | B.Trainings. | C.Sounds. | D.Rhymes. |
A.Continuous filming of cats’ responses. | B.Comprehensive analyses backed by software. |
C.Multi-dimensional evaluations of cats’ habits. | D.Further reference to previous studies on dogs. |
A.Lack of sample types. | B.Absence of owners’ support. |
C.Absence of scientific tools. | D.Lack of experts’ involvement. |
【推荐2】One spring day, once the flowers have begun to open, a bee will hover (盘旋) and zip through your yard and dive-bomb your picnic table. While you're thinking about avoiding an attack, that bee is focused on something else entirely: me.
A honeybee has about six weeks to live. Today, like most days, her task is to fly as many as three miles from home, stick her long, straw-like tongue into a hundred or so flowers. When the bee has had her fill, she’ll fly home. There the bee will deposit what she has got into the mouth of one of her co-workers, who will relay it to another, and so on for about 20 minutes, until the mixture is ready to be placed into the comb. Then she and her 50 000 or so mates will hover in the dark all night every night, flapping their wings to create hot, breezy conditions to remove the water from the mixture. Several sunrises later, they will seal me off in a golden cell of beeswax. In her lifetime, our bee may visit 4,000 flowers, and yet will produce only one-twelfth of a tea spoon of me.
The average American consumes nearly a pound and a half of me every year, in tea, on toast, and beyond. If I do say so myself, I am a timeless treasure. Literally---I never go bad.
Alas, my good health is not guaranteed. The problem lies in the growth of industrial agriculture and the use of pest control chemicals, as well as changes in weather patterns, all of which reduce the number of flowers bees have to visit I'd appreciate your letting your own garden grow just a little wild My future depends on all of us fostering spring and summers wild flowers, thus helping the bees, who give so much---to you, to me---without ever asking for anything in return..
1. What does " me" refer to in the passage?A.The flower | B.The bee. |
C.Water | D.Honey |
A.Bees' special talent | B.Bees' hard work. |
C.Bees' living environment. | D.Bees' social behavior. |
A.To appeal for help for honeybees. |
B.To talk about the history of a treasure. |
C.To put forward techniques for gardeners. |
D.To argue against the control of chemicals. |
【推荐3】The colorful anemonefish (海葵鱼), also known as clownfish, possesses a cheerful and carefree image among humans. However, their actual behavior might not always align with the family-friendly portrayal seen in a Pixar film. They can aggressively defend their territory against other anemonefish they perceive as threats.
To investigate how these fish identify group members, a team from Japan conducted two experiments with lab-raised common clownfish that had never encountered any other species.
In the first experiment, researchers introduced different species of anemonefish, distinguishable by the number of white bars on their bodies, into a tank in small cases. They observed that the common clownfish were particularly hostile toward members of their own species that displayed three white bars. These fish fought 80 percent of their specific-targeted fish for up to three seconds. In contrast, invaders from other species, like the orange skunk clownfish with no side bars and a white line along its back, were barely attacked. The two-barred Clarke’s clownfish and three-barred saddleback clownfish were “mildly bullied”, according to the team.
During the second experiment, the researchers exposed a colony of clownfish to various plastic discs. The discs were painted with anemonefish coloration and measured the level of aggression towards these artificial models. Similar to reactions to live fish, models with two bars were less frequently attacked, and those without any bars saw the least aggression. According to study co-author and ecologist Kina Hayashi, the findings “suggest that clownfish is capable of counting the number of bars to recognize the species of the invader”.
The team also found that a rigid hierarchy (社会等级) within clownfish colonies determines which specific fish attack the invader. Earlier studies have shown that the social position of the clownfish is determined by very slight differences in size. This study used fish that had not matured and were in a lab setting, but the team still observed the same size-based hierarchy. The largest clownfish led the charge against the invader.
1. What does the underlined word “hostile” mean in the third paragraph?A.Unfriendly. | B.Tolerant. | C.Patient. | D.Sympathetic. |
A.By introducing a new concept. | B.By comparing different clownfish. |
C.By observing clownfish’ behaviors. | D.By analyzing statistics of previous studies. |
A.Clownfish can’t reach maturity in a lab setting. |
B.Skunk clownfish is the most modest clownfish. |
C.The social position of a clownfish depends on its size. |
D.Clownfish identify threats by the number of vertical bars. |
A.Barred and Bullied: Attacks from Anemonefish. |
B.Clownfish and Conflicts: Strict Social Hierarchies. |
C.Beyond the Screen: The identification of Clownfish. |
D.From Lab to Tank: Aggression Among Anemonefish. |
【推荐1】The word listen, as is shown in Longman Dictionary, means paying attention to what someone is saying or to a sound that you can hear. Listening is definitely an important skill in communication. “When people talk, listen completely.” Those words of Ernest Hemingway might be a pretty good guiding principle for many managers. After all, people like being listened to.
Some firms use a technique known as a “listening circle”. In such a circle, only one person can talk about the issues they face at a time and there is no interruption. A study cited in the Harvard Business Review found that employees who had taken part in a listening circle subsequently suffered less social anxiety and had fewer worries about work-related matters than those who did not.
Listening has been critical to the career of Richard Mullender, who was a hostage (人质) negotiator, dealing with everything from suicide interventions to international kidnaps (绑架). He defines listening as “the identification, selection and interpretation of the key words”. It is crucial to all effective communication.
Plenty of people think that good listening is about nodding your head or keeping eye contact. But that is not really listening, Mr Mullender argues. A good listener is always looking for facts, emotions and indications of the other person’s values. Another important point to bear in mind is that, when you talk, you are not listening. The listener’s focus should be on analysis.
Of course, a listener needs to speak occasionally. One approach is to make an assessment of what the other person is telling you and then check it with them. For example, you can check with the other person by saying “It seems to me that what you want is…”. That gives the other party a sense that they are being understood. The fundamental aim is to build up a relationship so the other person likes you and trusts you, Mr Mullender says.
1. What can we learn about a “listening circle”?A.A listening circle focuses on personal issues. |
B.In a listening circle, a speaker won’t be interrupted. |
C.A listening circle increases worries about work-related matters. |
D.Employees get rid of social anxiety by taking part in a listening circle. |
A.Critical. | B.Opposed. | C.Cautious. | D.Favorable. |
A.To be liked and trusted by the other person. |
B.To check our assessments with the other person. |
C.To make assessments of what the other person is saying. |
D.To have a sense of being understood by the other person. |
A.The Analysis of a Listening Circle |
B.The Tricks of Successful Listening |
C.The Misunderstanding of Listening |
D.The Necessity of Effective Listening |
【推荐2】Five years ago, French navy officer Chardon was listening to a radio program about the journey of the bar-tailed godwit (斑尾塍鹬) , a bird that flies 14,000 kilometers between New Zealand and Alaska. Chardon understood how dangerous the journey would be, as heavy storms frequently hit Pacific island communities. Yet, somehow, bar-tailed godwits routinely pass through the area uninjured. Chardon wondered whether learning how godwits navigate (导航) could help coastal communities avoid disasters. Could tracking birds help save lives?
This past January, a team began experiments designed to test Chardon’s idea. Researchers led by Jiguet equipped 56 birds of five species with cutting-edge animal tracking technology. The team were transported to remote islands in French Polynesia, where they attached tags (追踪器). These tags send the birds’ locations to the International Space Station, which sends the data back to scientists on Earth who can then follow the birds — all the while waiting to see how the birds respond to natural disasters.
The project is focusing on birds’ ability to hear infrasound, the low-frequency sound humans cannot hear. Researchers believe it’s the most likely signal birds would use to sense storms and tsunamis. In a 2014 study, scientists tracking golden-winged warblers in the central and southeastern US founded the birds flew up to 1,500 kilometers to escape from the outbreak of tornadoes that killed 35 people. This showed they’d heard the storm system in advance.
The team plan on tagging more birds across the Pacific to prepare for a potential tsunami. “I think if there’s one wave that spreads across islands, we should get data from different species at different locations,” says Jiguet. “That’d definitely show it’s worth continuing to tag birds and to develop local systems to better analyze this.”
Even if the attempt to develop a bird-based tsunami early warning system fails, the project will still help scientists protect birds. In that sense, the research will have already gained results by that time. Jiguet says their first season’s tracking data shows Hawaii is an important stepping stone for the birds they tagged — a useful clue to the protection of these species above rising seas.
1. What is the purpose of Jiguet’s experiments?A.To learn more about birds’ lifestyles. | B.To know birds’ reactions to disasters. |
C.To test an animal tracking technology. | D.To study birds’ adaptation to nature. |
A.To present a fact. | B.To make comparisons. |
C.To take a guess. | D.To introduce a new sound. |
A.Successful. | B.Challenging. | C.Regrettable. | D.Rewarding. |
A.Can birds predict most natural disasters? |
B.How do we develop a warning system? |
C.Can birds warn us of natural disasters? |
D.How do birds avoid natural disasters? |
【推荐3】Encouraging life to bloom in the middle of a desert is no easy task. But one company, The National Advisor Bureau, in the United Arab Emirates has come up with a unique plan to provide drinking water for the state’s citizens. The firm intends to pull icebergs from Antarctica to the gulf coast in order to harvest its billions of gallons of fresh water. One iceberg could provide enough for one million people over five years, according to the company. And the scheme could begin as early as the start of 2018.
The firm’s director says they have already travelled the transportation route and used simulators to check the practicality of the scheme, according to reports in Gulf News. Speaking to the site about what he is calling the UAE Iceberg Project, Abdullah Mohammad Shehi said: “we predict that it will take up to one year to tow (拖拉) an iceberg to UAE.” We have made the technical and financial plan. Towing is the best method. We will start the project in beginning of 2018. “We want it mainly for the water. It could also be good for tourism and the weather.”
The UAE is one of the most dry countries and one of the top 10 most water-scarce in the world, due to its extremely dry climate, which receives less than four inches (100 mm) of rainfall per year. Despite that, it consumes more water than double the global national average, putting the country at severe risk of droughts over the next 25 years. An average iceberg contains more than 20 billion gallons of water, according to the Abu Dhabi-based company. They take a long time to melt as 80 percent of their mass is underwater, while the white ice above reflects sunlight, reducing its heat. Upon arrival at a specially constructed processing facility, workers will “mine” the icebergs for their water supplies. Blocks of ice will be sliced and placed in giant tanks, before being filtered and processed. “This is the purest water in the world”, Mr Al Shehi added. He also claims the iceberg’s presence could provide a more moist micro-climate in the area, perhaps even prompting rainfall. And the project may prove a boost for tourism if it proves a success, with people travelling to see the unusual sight of an iceberg off the coast of the Arabian Gulf.
1. What is the main purpose of The National Advisor Bureau’s scheme?A.To boost tourism and ease financial burden in UAE. |
B.To save endangered wildlife and boost tourism in UAE. |
C.To make drinking water accessible to the people in UAE. |
D.To get the purest water in the world for the citizens in UAE. |
A.A type of mining tool to carve out the iceberg. |
B.An electronic device to create and store energy. |
C.A vehicle to transport the iceberg from Antarctica. |
D.A piece of equipment to test potential conditions. |
A.The special electronic devices to keep the iceberg frozen. |
B.The time of processing iceberg before being transported. |
C.Much of the iceberg lying under water with ice above reflecting light. |
D.The floating of the iceberg in the seawater with a more moist micro-climate. |
A.Favorable. | B.Cautious. | C.Ambiguous. | D.Disapproving. |