Up to one fifth of the Amazon rainforest is emitting more carbon dioxide (CO2), than it absorbs, new research suggests.
Results from a decade-long study of greenhouse gases over the Amazon rainforest appear to show around 20% of the total area has become a net source of CO2 in the atmosphere. One of the main causes is deforestation. While trees are growing, they absorb CO2 from the atmosphere; dead trees release it again. However, the fact is that millions of trees have been lost to logging and fires in recent years.
The results of the study, which have not yet been published, have implications for the effort to combat climate change. They suggest that the Amazon rainforest, a vital carbon “store”, or “sink”, that slows the pace of global warming may be turning into a carbon source faster than previously thought. Every two weeks for the past 10 years, a team of scientists led by Professor Luciana Gatti, a researcher at Brazil’s National Institute for Space Research (INPE), has been measuring greenhouse gases by flying aircraft fitted with sensors over different parts of the Amazon basin. What the group found was startling: while most of the rainforest still retains its ability to absorb large quantities of CO2 — especially in wetter years — one portion of the forest, which is especially heavily deforested, appears to have lost that capacity.
Gatti’s research suggests this south-eastern part of the forest, about 20% of the total area, has become a carbon source. “Each year is worse,” she told Newsnight. “We observed that this area in the south-east is an important source of carbon. And it doesn’t matter whether it is a wet year or a dry year. 2017 was a wet year, but it didn’t make any difference.”
A forest can become a source of carbon rather than a “store”, or “sink”, when trees die and emit carbon into the atmosphere. Areas of deforestation also contribute to the Amazon’s inability to absorb carbon.
Carlos Nobre, who co-authored Prof Gatti’s study, called the observation “very worrying” because “it could be showing the beginnings of a major tipping point”. He believes the new findings suggest that in the next 30 years, more than half of the Amazon could transform from rainforest into savanna (稀树草原).
1. What can be concluded from Paragraph 2?| A．Logging and fires should be held responsible for all dead trees. |
| B．Amazon rainforest can no longer absorb as much CO2 as before. |
| C．Growing trees are able to absorb and release CO2 at the same time. |
| D．More than 20% of the Amazon rainforest has become a net source of CO2. |
| A．Most of the Amazon rainforest absorbs more CO2 in wetter years. |
| B．The Amazon rainforest is on its way to becoming the biggest source of carbon. |
| C．Deforested areas tend to perform better in terms of absorbing carbon in dry years. |
| D．The Amazon rainforest has completely lost its ability to slow the pace of global warming. |
| A．Striking. | B．Convincing. |
| C．Confusing. | D．Disgusting. |
| A．Deforestation or reforestation? |
| B．A carbon absorber or a carbon maker? |
| C．Cheering news about the Amazon rainforest |
| D．Thrilling facts about the Amazon rainforest |
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【推荐1】Eight months after China put a 10-year ban on fishing in the Yangtze River, a group of about 10 Yangtze finless porpoises (江豚) were seen in the river of Wuhan, Hubei Province. Their appearance was said to be a result of less interference (干涉) from human activities or an increase food availability.
“Rising water levels during the flood season and the fishing ban may both contribute to this rare animal’s appearance. Without interference from human activities, the finless porpoises might be more active,” said Zhang Xianfeng, an aquatic (水生的) wildlife researcher.
The finless porpoise is widely believed to be an important health indicator of the Yangtze River. Over the past 40 years, its population has declined dramatically due to many factors, such as climate change and habitat loss. In 2013, it was classified as “critically endangered” by the International Union for Conservation of Nature. However, the population has shown some stability in recent years thanks to joint protection from government organs, research institutes and other social organizations.
Zhang believes it’s a good thing that the public has become more aware of the urgency of saving the finless porpoise and protecting the ecosystem of the Yangtze River. However, the appearance of the finless porpoises cannot necessarily be seen as a sign that the population is increasing. Its total population, around 1,000, is very limited, which makes the chances for them to have babies very slim in such a long river as the Yangtze River.
To preserve biodiversity along the Yangtze River, China imposed a 10-year fishing ban in 332 conservation areas, protecting not only the finless porpoise but also more than 4,300 kinds of aquatic life living in the Yangtze River. The fishing ban, which is crucial to ecological restoration of the whole river, will significantly expand the finless porpoise’s food supply and remove the threat from fishing tools. However, the effect will be known only after three to five years.
1. What is Paragraph 2 mainly about?| A．The effect of the 10-year fishing ban. |
| B．The living conditions of finless porpoises. |
| C．The necessity of limiting human activities. |
| D．The reasons for finless porpoises’ appearance. |
| A．The limited population. |
| B．The human interference. |
| C．The lack of public awareness. |
| D．The length of the Yangtze River. |
| A．It was put into effect in Hubei Province. |
| B．It aims to protect a variety of aquatic life. |
| C．It increased the number of finless porpoises soon. |
| D．It forbids human activities along the Yangtze River. |
| A．To show the effect of a 10-year fishing ban. |
| B．To introduce the features of finless porpoises. |
| C．To record the appearance of finless porpoises. |
| D．To advocate the protection of the Yangtze River. |
【推荐2】The beautiful blue whale is the largest animal in the sea and can weigh as much as 200 tons. Blue whales, like so many of the species, have been considered seriously endangered but a new Antarctic survey shows an obvious increase in numbers. This is certainly something to celebrate.
The 21-day 2020 survey led by the British Antarctic Survey (BAS), shows that blue whales and other whale species are making a comeback in the cold Antarctic waters. The survey marked the end of a three-year wild water project off South Georgia Island in the South Atlantic.
The survey included 40 researchers from nine countries. It took place in the most heavily hunted waters in the world where 176,000 whales were caught in around 60 years of hunting operations from shore stations on the island and from factory whaling ships. The researchers have spotted 55 whales in 36 sightings already in 2020 in a location where only one whale was spotted in 2018. The scientists were able to recognize the whales acoustically (声学上) through their songs — blue whales are also the loudest animals on Earth.
The new survey is extremely important because South Georgia’s waters are a major krill (磷虾) feeding area for different whale species. In all, BAS estimated that 2000 whales of different species now spend the summer in South Georgia before heading north to breed. “After three years of surveys, we are excited to see so many whales visiting South Georgia to feed again,” whale project leader Jennifer Jackson said.
With increased awareness and protection efforts, species on land and in the sea can be preserved and their numbers can increase. We may not be able to restore all of the biodiversity (生物多样性) that once existed, but we can preserve what remains.
1. What is the good news according to paragraph 1?| A．People realize the serious situation of blue whales. |
| B．The number of blue whales has increased greatly. |
| C．Blue whales have become the largest animals in the world. |
| D．Scientists have found many special species of blue whales. |
| A．The end of studying whales. | B．The end of a wild water project. |
| C．The success of protecting whales. | D．The success of fighting against hunting. |
| A．By their loud voice. | B．By their large size. |
| C．By their special smell. | D．By their beautiful color. |
| A．There is little water pollution in the research area. |
| B．The waters studied are the main food source for whales. |
| C．The study raises people’s awareness of protecting blue whales. |
| D．The survey provides a lot of detailed information about whales. |
【推荐3】Every year, people all around the world come together to celebrate Earth Day with lots of different activities. Earth Day events typically have one theme in common: the desire to show support for environmental issues and teach future generations about the need to protect our planet.
The very first Earth Day was celebrated on April 22,1970. The event, which some consider to be the birth of the environmental movement, was founded by United States Senator Gaylord Nelson.Nelson chose the April date to coincide (同时发生) with spring while avoiding most spring break and final exams. He hoped to call for college and university students for what he planned as a day of environmental learning and activism.
Participants(参与者) from 2, 000 colleges and universities, roughly 10,000 primary and secondary schools, and hundreds of communities across the United States got together in their local communities to mark the occasion of the very first Earth Day. Almost 20 million Americans filled the streets of their local communities on that first Earth Day, demonstrating in support of environmental issues.
Earth Day is now observed in 192 countries,and celebrated by billions of people around the world. Events can be found everywhere from tree planting activities at your local park to online parties that share information about environmental issues. In 2011, 28 million trees were planted in Afghanistan by the Earth Day Network. In 2012, more than 100 ,000 people rode bikes in Beijing to raise awareness about climate change and help people learn what they could do to protect the planet.
How can you get involved? The possibilities are endless. Pick up trash in your neighborhood. Make a commitment to reduce your food waste or electricity use. Plant a tree. Talk to your friends and family about environmental issues.The best part? Make every day Earth Day and help to make this planet a healthy place for all of us to enjoy.
1. What is the purpose to celebrate Earth Day?| A．To take part in activities. | B．To protect our earth. |
| C．To pay attention to education. | D．To gather worldwide people. |
| A．Teachers. | B．Officials. | C．Students. | D．Researchers. |
| A．Its participants. | B．Its motivation. | C．Its history. | D．Its influence. |
| A．Take specific action. | B．Reflect on our behavior. |
| C．Come up with good ideas. | D．Answer some questions. |
【推荐1】China’s existing COVID-19 containment strategy, characterized by firm and rapid response to cut its transmission and block new outbreaks, should be sufficient for dealing with the new Omicron variant（变种）of the novel coronavirus, health experts and officials said recently.
They added that the country’s dynamic zero-case policy should continue to be enforced this winter and spring, as new modeling shows that dropping it prematurely would risk causing “a huge outbreak”.
Wu Zunyou, a chief epidemiologist, said the new variant appears to be more contagious（传染的）than the Delta variant due to its exceptionally high number of spike mutations.
“But no matter how the virus mutates, regular public health measures, such as wearing masks, maintaining social distancing and washing hands, will be effective against all variants,” Wu said.
Zhang Wenhong, a well-known doctor from Shanghai, said China’s current “rapid response and dynamic zeroing of new infections” can deal with all variants.
The strategy has also enabled China to win a window of opportunity in terms of building up scientific support to fight the virus, he said. Ongoing work includes increasing reserves of vaccines（疫苗）and drugs to support the global battle against the pandemic, and boosting inventories（存货）of China’s public health and medical resources.
According to Wu Zunyou, China’s overall epidemic situation remains stable and under control against a backdrop of surging infections globally. “This remarkable outcome is largely due to the central approach of interrupting the spread of the virus, blocking new outbreaks and implementing quarantine（隔离）for incoming travelers,” he said.
“By the most conservative estimates, the strategy had avoided 47.8 million COVID-19 infections and 950, 000 related deaths in China,” he said.
As the outlook for the pandemic remains serious for this winter and spring, Wu said these measures should continue to be enforced.
“Adjustment（调整）of virus control measures should be done extremely carefully and with every detail and procedure being taken into consideration, so as to avoid making mistakes or taking the wrong path,” he said.
1. What might be the best title of this newspaper article?| A．China’s COVID-19 strategy can cope with Omicron. |
| B．China’s CVID-19 approach has made great achievements. |
| C．New Omicron variant appears to be more contagious. |
| D．New Omicron variant calls for adjustment of measures. |
| A．Traditional and immature. | B．Solid and effective. |
| C．Regular and risky. | D．Dynamic and contemporary. |
| A．cultural exchanges | B．economic recovery |
| C．scientific preparations | D．medical profits |
| A．The Delta Variant of COVID-19 will soon disappear. |
| B．New variant makes it harder to maintain social distancing. |
| C．The dynamic zero-case policy will continue for a while. |
| D．This winter and spring will see fewer cases of infection. |
【推荐2】Feeling inactive at work? Indoor pollution might play a part. A new study by scientists at Harvard has found that the air quality inside an office can have a significant impact on employees cognitive (认知的) function.
"The limited amount of previous studies on indoor settings focused on measures like thermal (热的) comfort and satisfaction, rather than on cognitive outcomes," Jose Guillermo Cedeno Laurent, a researcher told AFP.
Jose and his colleagues designed a study that followed 302 office workers across six countries over a period of a year, all of whom were aged between 18 and 65 and worked at least three days in an office building. Their workspaces were fitted with an environmental sensor to monitor real time concentrations of PM2.5. The participants were given a custom-designed app on their phones to carry out the cognitive tests, which they were reminded to take at prescheduled times or when PM2.5 levels fall below or rise beyond certain thresholds (临界点).
There were two tests for the participants. The first required them to correctly identify the color of displayed words that spelled out another color. This evaluated cognitive speed. The second test involved basic calculation with long numbers to assess cognitive speed and working memory.
Results showed that an increase of 10 micrograms per cubic meter of PM 
led to about a one percent reduction in response times, and more than a one percent reduction in accuracy.
"While past studies have shown that prolonged exposure to PM2.5 damages the central nervous system and causes long-term neuro diseases, this is the first to show short-term effects on people's cognitive abilities," Jose told AFP.
For employees returning to in-person office work, it is time to open a window for fresh air. If the outdoor air quality isn't good, adding high quality portable air cleaners is a good choice.
1. What's the function of the environmental sensor?| A．To monitor indoor air quality. |
| B．To evaluate workers'job performance |
| C．To improve working environment. |
| D．To develop workers' memory accuracy |
| A．Giving examples. | B．Analyzing causes. |
| C．Making comparisons. | D．Confirming assumptions. |
| A．polluted air destroys one's nervous system |
| B．an air cleaner is a must in an office building |
| C．indoor setting determines a person's productivity |
| D．fresh air contributes to a person's cognitive accuracy |
【推荐3】Stephen Hawking, one of the world’s most famous scientists, believed that to survive, humans will one day have to move into space. “Once we spread out into space and establish independent settlements, our future should be safe, ”he said.
Today, several leading countries in space exploration are all planning to send astronauts-people who travel into space - back to Earth’s closest neighbor: the moon. Some of these countries want to create space stations there within the next 10 years. These stations will prepare humans to visit and later live on Mars or other Earthlike planets.
Robert Zubrin, a rocket scientist, thinks humans should take control of space. He wants to start with Mars. Why? He thinks sending people to Mars will allow us to learn a lot of things-for example, the ability of humans to live in a very different environment. Eventually, we could create new human societies on other planets. In addition, any advances we make in the fields of science, technology, medicine, and health will benefit people here on Earth.
Not everyone thinks sending humans into space is a smart idea. Many say it’s too expensive. Also, most space trips are not short. A one-way trip to Mars, for example, would take at least six months. People traveling this kind of distance could face many health problems In addition, these first people would find life extremely difficult in space. On the moon, for example, the sun’s rays are very dangerous. People would have to stay indoors most of the time
Despite these concerns, sending people into space seems certain. In the future, we might see cities on the moon or even new human cultures on other planets. First stop: the moon
1. What is Stephen Hawking’s idea about future life in space?| A．Humans will live a healthy life. |
| B．Humans will live a better life on the moon. |
| C．Humans will create hospitals on other planets. |
| D．Space will be a safe place for humans to live in. |
| A．To learn more about the moon’s surface |
| B．To improve cooperation among countries. |
| C．To prepare humans to live on other planets |
| D．To reduce the number of people living on Earth |
| A．It will take a long time |
| B．It will cost a lot of money |
| C．It will be extremely difficult. |
| D．It will benefit people on Earth a lot |
| A．Positive. | B．Negative. |
| C．Unclear. | D．Worried. |
| A．A Trip to Mars. | B．Living in Space. |
| C．Astronauts on the Moon. | D．The Exploration of Space. |
