Between a quarter and one third of all marine species rely on coral reefs (珊瑚礁)at some point in their life cycle. The Great Barrier Reef, the world's largest coral reef, covers nearly 133,000 square miles and is home to more than 1,500 species of fish, 411 species of hard coral and dozens of other species.
Australian's Great Barrier Reef has lost 50% of its coral populations in the last three decades, with climate change a key driver of reef disturbance, a new study has found.
Researchers from the Centre of Excellence for Coral Reef Studies, in Queensland, northeastern Australia, studied coral communities and their colony size along the length of the Great Barrier Reef between 1995 and 2017, finding reduction of virtually all coral populations.
“We found the number of small, medium and large coral on the Great Barrier Reef has dropped by more than 50% since the 1990s," reported co-author Terry Hughes, a professor at the centre, in a statement.
Reefs are basic to the health of marine ecosystems — without them, ecosystems collapse, and marine life dies. Coral population sizes are also considered important when it comes to the coral's ability to reproduce." A coral population has millions of small, baby corals, as well as many large ones,“ said Andy Dietzel, a doctoral student in a statement. "Our results show the ability of the Great Barrier Reef to recover becomes weak compared to the past," he added.
Population falls occurred in both shallow and deep water coral species, experts found, but branching coral and table-shaped coral — which provide habitats for fish — were worst affected by mass bleaching （白化）events in 2016 and 2017, caused by record-breaking temperatures.
Warm ocean temperatures are the main driver of coral bleaching, when coral turns white as a stress response to water that is too warm. Bleaching doesn't kill coral immediately, but if temperatures remain high, eventually the coral will die, destroying a natural habitat for many species of marine life.
The new study found the serious worsening of coral colonies in the Northern and Central Great Barrier Reef following the mass bleaching events in the past five years, and experts said the southern part of the reef also suffered record-breaking temperatures in early 2020.
“We used to think the Great Barrier Reef is protected by its huge size — but our results show that even the world's largest and relatively well-protected reef system is increasingly dropping, Hughes said. He warned that climate change is driving an increase in the frequency of the reef disturbance like marine heat waves. "There is no time to lose — we must sharply reduce greenhouse gases as soon as possible," he said.
1. What can we know about coral reefs?| A．They are not able to recover by themselves. |
| B．They make up the largest ecosystem in the sea. |
| C．They can easily be disturbed by other marine species. |
| D．They can influence the existence of other marine species. |
| A．Change. | B．Disappear. |
| C．Crash. | D．Progress. |
| A．It will die very soon. | B．It will change its color. |
| C．It will fail to reproduce. | D．It will kill other species. |
| A．The Great Barrier Reef doesn't have a self-protecting mechanism. |
| B．The Great Barrier Reef is no longer the world's largest coral reef. |
| C．Measures must be taken to protect coral reefs without delay. |
| D．Climate change can increase the frequency of heat waves. |
相似题推荐
【推荐1】What Recycling Will Look Like in 10 Years
As businesses rush to become greener, this is what recycling may look like a decade from now. To begin with, more goods will be made of existing materials. The increase in the reuse of existing materials, including recycled plastics, glass and more will reduce the demand for raw materials (原材料). You’ll find more clothing, toys, park benches, etc. made of recycled water bottles.
Reusable products will become more popular. Not only will companies take up the duty to reduce waste.
Chemical recycling may become common. Though the field is still in its early stages, the process of chemical recycling may increase in the coming years.
| A．We cannot rely only on recycling |
| B．New plastic is cheaper than recycled plastic |
| C．In the future, thin plastics will be recycled more readily |
| D．However, chemical recycling is not without disagreement |
| E．This creates an economy where no resource will be wasted |
| F．Individuals (个人) will also be expected to use more reusable products |
| G．The campaign puts the focus on individuals to clean up their plastic mess |
【推荐2】India and China are leading the global greening effort, a latest NASA study said, observing that the world is a greener place than it was 20 years ago.
Data from NASA’s satellites show that human activities in China and India play an important part in this greening of the planet, thanks to tree planting and agriculture. The effect comes mostly from tree-planting programs in China and intensive agriculture (集约农业) in both countries. “China and India account for one-third of the greening,” said lead author Chi Chen of Boston University.
China alone accounts for 25 percent of the global net increase in leaf area with only 6.6 percent of global vegetated (有植被的) area. The greening in China is from forests and farmland, but in India, it is mostly from farmland with minor contribution from forests. China’s great contribution to the global greening trend comes in large part from its programs to protect and expand forests.
“When the greening of the earth was first observed, we thought it was due to a warmer, wetter climate and fertilization (施肥) from the added carbon dioxide (CO2) in the atmosphere. Now with the satellite data, we see that humans are also contributing,” said Rama Nemani, a research scientist at NASA’s Ames Research Center. “Once people realize there is a problem, they tend to fix it. In the 1970s and 80s in India and China, the situation about vegetation loss was not good. In the 1990s, people realized it, and today things have improved. That’s what we see in the satellite data,” added Nemani.
The land area used to grow crops is comparable in China and India, and has not changed much since the early 2000s. Yet both countries have greatly increased both their annual total green leaf area and their food production. This was achieved through multiple cropping practices, by which a field is replanted to produce another harvest several times a year. Production of grains, vegetables, fruits and more has increased by about 35% — 40% since 2000 to feed their large populations.
1. Where did the greening mainly come from in India?| A．Croplands. | B．Tree planting. |
| C．Forests and farmland. | D．A warmer and wetter climate. |
| A．Carbon dioxide causes global warming. |
| B．Man can actively change the environment. |
| C．In India and China, vegetation loss has been solved. |
| D．Climate has little to do with the greening of the earth. |
| A．India and China are guiding the global greening. |
| B．Human activities change the global climate. |
| C．Climate change contributes to the global greening. |
| D．The land area for crops in China and India has changed much. |
【推荐3】Food miles are the total distance food travels before being sold. Our food tends to be less tasty and less healthy after traveling long distances. What’s more, the farther food travels, the more it contributes to emitting greenhouse gases. Cape Eleuthera Island School in the Bahamas shows us a delicious way to cut food miles.
Food on campus travels just steps from the gardens to the plates. The school uses an aquaponic system on campus for growing vegetables, which are served in its dining hall. Under this system, the plants get their nutrition from recycled fish waste, while fish swim around in big tanks of water and dirty water gets pumped to the vegetable. Fish waste feeds the plants and the plants purify the water, returning clean H2O to the tank. The aquaponic system uses much less water than traditional farming and is less dependent on good weather.
Students from around the world spend a semester learning hands-on experiences here. Digging in the dirt, doing fieldwork on the farm, students are taught at the aquaponic garden to harvest the lettuce and put it in buckets ready for delivery. No trucks or cars needed for transport. It’s only a bicycle ride or a short walk along the bridge made from recycled rubber and plastics to the dining hall kitchen. All the fruits, vegetables, and fish grown, harvested on campus stay on campus.
The students will leave the Island School as confident teens to lead an eco-aware life at home. “When I returned home, I threw myself into sustainability-related projects.” says Anna, a spring 2020 student. Anna and her friends use cloth napkins and reusable straws. “We usually walk and bike,” she adds. “When the weather is terrible, we carpool.”
Students at the Island School are helping to change the planet by living what they’ve learned and reducing their food miles, one meal at a time.
1. Why does Cape Eleuthera Island School grow its own food?| A．To reduce food miles. | B．To grow more tasty food. |
| C．To feed the students on campus. | D．To teach students hand-on skills. |
| A．They provide food for the plants. | B．They can be sold in the market. |
| C．They clean water for the plants. | D．They are used to decorate the big tanks. |
| A．Using the water-saving aquaponic system. |
| B．Building bridges from recycled rubber. |
| C．Serving campus-grown vegetables in its dining hall. |
| D．Teaching students to work at the aquaponic garden. |
| A．It showed her how poorly she was eating before. |
| B．It caused her to change her habits to be more sustainable. |
| C．It showed her how to make connections with her friends. |
| D．It taught her to set up an aquaponic system back home. |
【推荐1】Children who spend too much time on smartphones and computers are at risk for a lifetime of health problems, including cancer-causing obesity ( 肥胖症 ) and eyesight problems, according to a new study.
The study, carried out by the World Cancer Research Fund (WCRF) in UK, found sedentary behaviors - like staring at an iPhone - are among the causes of people ’ s weight gain. The review shows that being overweight or obesity is related to several types of cancer, including breast and stomach, but physical activity can reduce that risk.
"New technologies have encouraged people to increase the time they spend on sedentary behaviors such as sitting in cars and watching television as well as using computers, mobile phones or other electronic devices, "the report said. "Low levels of physical activity have been linked to a number of health problems including heart disease, stroke, diabetes, obesity, poor bone health and depression.
According to the study, 14.1 million people across the globe were diagnosed (诊断) with cancer in 2012 and 8.2 million died from cancer, but that about 40 percent of cancer cases can be prevented. "This global cancer burden is expected to increase to 21.7 million cases and 13 million deaths by 2030,” it said.
WCRF also warned that a lot more snacks will be eaten as a result of spending too much time on screen and lack of physical activity. It said about 1.97 billion adults and more than 338 million children around the world were considered overweight in 2016.
Meanwhile, kids who love playing video games are at a greater risk for developing "digital myopia ” (数字近视). For every hour a child plays video games, their risk for short-sightedness increases by 3 percent. The number of children suffering from myopia has doubled over the last 50 years, from 7.2 percent to 16.4 percent-and experts conclude that the shocking number is a result of too much screen time.
1. What did the study find about obesity?| A．It is related to eyesight problems. | B．It can lead to sedentary behaviors. |
| C．It may cause some kinds of cancers. | D．It results in more physical activities. |
| A．They put people's health at risk. | B．They are mainly related to kids. |
| C．They affect new technologies. | D．They were caused by mobile phones. |
| A．suggest ways of protecting eyes |
| B．show the strong effects of video games |
| C．call on experts to take numbers seriously |
| D．explain the bad effects of short sightedness |
| A．Pessimistic. | B．Worried. | C．Angry. | D．Unclear. |
| A．persuade people to pay attention to new technology |
| B．introduce ways of preventing sedentary behaviors |
| C．compare cancer cases in different periods of time |
| D．warn people of the harm of too much screen time |
【推荐2】From 1990 to 2000, fishermen trying to get swordfish (剑鱼) off the coast of California accidentally caught and killed over 100 sea turtles (海龟), and injured many more. In 2001, the government set up the Pacific Leatherback Conservation Area (PLCA), an area off the coast of California where fishing boats are not allowed to enter from August to November. Since then, the number of turtles killed by mistake has fallen rapidly, but a small number of animals still die from being caught in fishing nets each year. And at the same time, the once $15 million swordfish industry has become a $ 2 million industry.
Scientists are hoping to find a way to not only protect sea turtles and other endangered creatures but also help fishermen make a living. For this, many scientists are looking at dynamic ocean management to help fishing boats meet fish where they are and avoid catching other creatures by mistake.
The first paper to suggest that the fish living in the open ocean should be guarded with fluid, ever-changing zones of protection, came out in 2000. Larry Crowder, a professor at Hopkins Marine Station, remembers reading it and thinking, “Cool idea, but it will never work.” In 2000, scientists didn’t have the computer power to cheaply test statistical models or deal with satellite data quickly. They didn’t have enough data dealing with fish or satellite data on ocean conditions, either.
Now scientists can download satellite data of oceans in minutes and attach satellite archival tag to sea animals to track their movements. They first collect data by marking the creatures, collecting reports from fishing boats, or other tracking ways. Then they compare that data with weather conditions, the time of year, and any other data that can be sensed. Finally, they can predict where fish probably are.
Crowder and his workmates used the data to develop a tool called EcoCast during the 2012 and 2015 fishing seasons, they could have fished in at least 125,000 square miles, without high risk of hunting turtles.
1. The government hoped that PLCA and its rules could .| A．prevent fishing in the PLCA |
| B．help collect data for future research |
| C．protect the creatures in the area to some degree |
| D．make the public realize the importance of our environment |
| A．unrealistic | B．stupid | C．possible | D．interesting |
| A．A great way to collect data. |
| B．Some technology fruits in this field |
| C．A scientific way to find new ocean animals |
| D．The way dynamic ocean management works |
| A．It protects the ocean from pollution. |
| B．It helps support the fishing industry. |
| C．It prevents fishermen from getting lost while fishing. |
| D．It both protects ocean animals and supports the fishing industry. |
【推荐3】Jeremiah Thoronka was born in the fighting of the Sierra Leone civil war and grew up in the gutter (贫民窟) on the suburbs of the capital Freetown, having to burn wood for lighting and heating. Jeremiah saw with his own eyes how, in addition to the smog making breathing problems common, his young contemporaries fell behind in their schoolwork because of a lack of decent lighting.
Energy poverty is a major issue in Sierra Leone—with just 26% of the population having access to electricity. In rural parts of the country, only 6% of people have electricity access, most of whom turn to solar lanterns and dry-cell batteries. As a result, it’s led to the destruction of forests as people cut down trees for firewood, which leaves Sierra Leone highly sensitive to extreme events like flooding and landslides. Families’ reliance on firewood also leads to frequent house fires.
These life-threatening disadvantages and hardships fuelled Jeremiah’s passion for renewable energy and climate change advocacy. At 17, when studying at the African Leadership University in Rwanda, he launched a start-up called Optim Energy that transforms vibrations (震动) from vehicles and footfall on roads into an electric current. It is different from established renewable energy sources including wind or solar because it generates power without relying on changeable weather.
Optim Energy ran a successful pilot program in Jeremiah’s neighbourhoods, Makawo in the northern part of Sierra Leone and Kuntoluh east of Freetown. With just two devices, the start-up provided free electricity to 150 households comprising around 1,500 citizens, as well as 15 schools where more than 9,000 students attend.
Jeremiah is currently developing plans to expand into the healthcare field, which needs power to cool medicines and create enough light for treating patients after dark.
1. What affected the young fellows’ academic performance?| A．The war. | B．The smog. | C．The poor lighting. | D．The breathing problem. |
| A．It is caused by solar lanterns and dry-cell batteries. | B．It has a worse impact on the city area. |
| C．It brings about the destruction of forests. | D．It increases the risk of forest fires. |
| A．It draws on vibrations to make electricity. | B．It upgrades the use of solar energy. |
| C．It runs a pilot program throughout the city. | D．It helps 9,000 students return to school. |
| A．Electricity is the lifeblood of the city. |
| B．Whoever is happy will make others happy too. |
| C．Life is either a daring adventure or nothing at all. |
| D．We are all in the gutter, but some are making it better. |
【推荐1】Rapid deforestation (毁林) of the Amazon rainforest could influence the temperature and precipitation (降水，降水量) over the Tibetan plateau 15, 000 kilometers away.
Saini Yang at Beijing Normal University in China and her colleagues analyzed global climatological data from 1979 to 2019 to identify relations in temperature and precipitation between the Amazon rainforest and other areas. Such links are called “teleconnection1s”. They focused on the Amazon rainforest in particular because of its significance as a major carbon sink and as a climatic “tipping point” (爆发点) that could see forest turn to savannah (稀树草原) beyond a certain threshold (阈，界) of warming and human-driven deforestation.
The researchers found that since 1979, warm temperatures in the Amazon rainforest were related to warm temperatures over the Tibetan plateau and the West Antarctic ice sheet; more precipitation in the Amazon rainforest was associated with less precipitation in those regions. By analyzing changing temperatures in the regions between the Amazon rainforest and those distant areas, they were also able to trace the path through which energy or materials such as black carbon released in forest fires might spread through the atmosphere. Their analysis showed the route remained consistent under different future warming scenarios.
The collapse of the West Antarctic ice sheet is a known tipping point. Melting snow on the Tibetan plateau is not, but the region is warming more rapidly than much of the rest of the globe, and changes to snow and ice there could have consequences for ecosystems and the billions of people that rely on its snowmelt for water, says Yang.
Victor Brovkin at the Max Planck Institute for Meteorology in Germany says the teleconnections are an interesting find, but is skeptical that variability in the Amazon rainforest causes the changes elsewhere. He says the Amazon rainforest is too small an area to overcome the influence of the tropical oceans and the researchers don’t present a physical mechanism to explain any influence.
If the Amazon rainforest does have an influence on these regions, however, it could mean there is à higher risk that the Amazon rainforest tipping point might set others off, says Jonathan Donges-at the Potsdam Institute for Climate Impact Research in Germany. “It adds an additional potential domino (多米诺骨牌) that can fall. ”
1. Why was the Amazon rainforest the focus for Saini Yang’s research?| A．Because it played a role as a main carbon sink. |
| B．Because it was the most important carbon sink. |
| C．Because it was very likely to turn to savannah. |
| D．Because it was at a high risk of becoming a climatic “tipping point”. |
| A．The benefits of the research. |
| B．The findings of the research. |
| C．The means of analyzing the data. |
| D．The results of the Amazon rainforest being deforested. |
| A．The temperature of the Tibetan plateau changes the fastest. |
| B．The variability in the Amazon rainforest may not lead to changes elsewhere. |
| C．The more the Amazon rainforest rains, the less rainfall the Tibetan plateau may have. |
| D．The consequences of the collapse of the West Antarctic ice sheet are little-known. |
| A．Teleconnections have kept the researchers interested for a long time. |
| B．The Amazon rainforest tipping point is likely to set off those of other areas. |
| C．The findings of the research on the Amazon rainforest are controversial. |
| D．The Amazon rainforest is large enough to remove the influence of the tropical oceans. |
“Storm at Sea”, a short poem written around 700, is generally regarded as one of mankind’s earliest artistic representations of the Atlantic.
When the wind is from the west
All the waves that cannot rest
To the east must thunder on
Where the bright tree of the sun
Is rooted in the ocean’s breast.
As the poem suggests, the Atlantic is never dead and dull. It is an ocean that moves, impressively and endlessly. It makes all kinds of noise—it is forever thundering, boiling, crashing, and whistling.
It is easy to imagine the Atlantic trying to draw breath—perhaps not so noticeably out in mid–ocean, but where it meets land, its waters bathing up and down a sandy beach. It mimics(模仿) nearly perfectly the steady breathing of a living creature. It is filled with symbiotic existences, too; unimaginable quantities of creatures, little and large alike, mix within its depths in a kind of oceanic harmony, giving to the waters a feeling of heartbeat, a kind of sub-ocean vitality. And it has a psychology. It has personalities: sometimes peaceful and pleasant, on rare occasions rough and wild; always it is strong and striking.
1. Unlike real inland seas, the Atlantic Ocean is ________.
| A．always energetic |
| B．lacking in liveliness |
| C．shaped like a square |
| D．favored by ancient poets |
| A．To describe the movement of the waves. |
| B．To show the strength of the storm. |
| C．To represent the power of the ocean. |
| D．To prove the vastness of the sea. |
| A．Living together. | B．Growing fast. |
| C．Moving harmoniously. | D．Breathing peacefully. |
| A．a beautiful and poetic place |
| B．a flesh and blood person |
| C．a wonderful world |
| D．a lovely animal |
【推荐3】When night falls in the Netherlands, lights dance across a farm and create a dreamy landscape. Here, in a field inspired by beauty and equipped with photobiology, art meets with agriculture. Yet, there is more than what meets the eye; these glowing lights also provide higher production and more sustainable crops.
This magical field is part of a project called GROW and was created by Dutch designer Daan Roosegaarde. Living in the city, he had a desire to connect people to the source（源头）of their food in an inspiring way. “How can we make the farmer the hero? We barely know where our food comes from,” Roosegaarde said in the video describing the project.
His vision was to combine science and art, and in so doing, create a better world. Desiring to offer the world light in dark times, he set to work in a 5-acre field of leeks（韭葱）. He used his own design concept alongside artists, a team of designers, and experts at the Wageningen University.
Using the science of photobiology, the group discovered that certain mixes of red, blue, and ultraviolet lights accelerate plant growth. The team then put LEDs in different places across the field. These lights move up and down in order to ensure the light is evenly distributed across the area. And when these lights move at night, they seem to dance, creating a poetic dreamscape. “It’s very futuristic and also very romantic, in a way,” Roosegaarde said.
Aside from being beautiful and promoting growth, the team observed that due to these lights, they needed to use 50 percent less pesticides（杀虫剂）on the crop. This is because this specific recipe of lights activated the defense system of the plants. And as it works on all crops, not just leeks, Roosegaarde foresees a way to reduce the use of pesticides on many other plants. And his project will soon be touring 40 countries, and sending its dancing lights across the world.
1. What message does Daan Roosegaarde try to convey in his video?| A．It’s important to know the source of food. |
| B．People living in cities desire to save food. |
| C．It’s easy to track where food comes from. |
| D．Farmers are considered as heroes by the public. |
| A．He invented low-cost pesticides. | B．He came up with the design concept. |
| C．He learned dancing skills in a college. | D．He bought 5 acres of leeks from farmers. |
| A．The lights make it more resistant to pests. |
| B．The lights kill off most of the pests on it. |
| C．The lights are too bright for pests to tolerate. |
| D．The lights are equipped with a defense system. |
| A．Dancing Lights—a Widespread Scene in the Field |
| B．Magical Fields Make Plants Beautiful in the Light |
| C．Plants in the Netherlands—Great Dancers at Night |
| D．Art Mixed with Science Improves Crop Production |
