Every spring, as the weather warms, trees up and down the East Coast explode in a display of bright green life as leaves fill their branches, and every fall, the same leaves provide one of nature’s great color displays of vivid yellow, orange and red.
Thanks to climate change, the timing of these events has shifted over the last two decades, Harvard scientists say.
Andrew Richardson, an associate professor of organismic and evolutionary biology, and research associate Trevor Keenan worked with colleagues from seven different institutions on a study which found that forests throughout the eastern United States are showing signs of spring growth dramatically earlier, and that the growing season in some areas extends further into the fall.
Richardson said, “Climate change isn’t just about warmer temperatures. It’s also about changes in precipitation (降水) patterns... so in the future, an earlier spring might not help forests take up more carbon dioxide if they end up running out of water in mid-summer.”
The research combined information from three sources. Using satellite data, Keenan tracked when forests across the region began to turn green in the spring, and when leaves began to turn yellow in the fall. Ground observations made every three to seven days at the Harvard Forest in Petersham and a long-term research site in New Hampshire provided information about the state of buds, leaves and branches. When combined with records from instrument towers, the data sets allowed the researchers to paint a richly detailed picture that shows spring starting earlier, and the growing season lasting longer than at any point in the past two decades.
Another important result, Richardson said, was the discovery of a significant source of error in existing computer models on how forest ecosystems work.
“This shows an opportunity to improve the models and how they simulate how forests will work under future climate scenarios forecast.” he said.
The real power of the findings, however, may be in helping to make the effects of climate change clearer to the public, the researchers said.
1. What is the reason of the earlier spring according to the Harvard scientists?A.The human activities. | B.The climate change. |
C.The tree growth. | D.The reduction in water. |
A.An earlier spring can only bring benefits. |
B.The influence of climate change is complex. |
C.The water in mid-summer will increase. |
D.The role of forests becomes less important. |
A.Change | B.Explain | C.Imitate | D.Create |
A.It helps scientists to figure out how forest ecosystems work. |
B.It reflects how the growing season is extending faster. |
C.It provides an opportunity to improve the computer models. |
D.It helps to make the effects of climate change clearer to the public. |
A.To tell us people should be more aware of the climate change. |
B.To tell us the climate change has some effects on the world. |
C.To tell us the early spring in eastern USA is a good time to travel. |
D.To tell us high technology is useful to detect the climate change. |
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【推荐1】Zulema Munoz collects seaweed in a small coastal town 100 miles south of Santiago, Chile. A good week may see her cut 1,100 pounds of seaweed from the rocks where it grows.
Muftoz is one of the 30, 000 people for whom Chilean seaweed industry provides a livelihood. Throughout Latin America, the cultivation (种植) and collection of seaweed are gaining a support both as a source of food and as a means of ensuring food security in a region where 34 million people are food insecure and poverty affects 47 percent of the rural population. Countries such as Argentina, Brazil, Colombia, Cuba, Ecuador, Mexico, Peru, and Venezuela have all explored seaweed production for food. Yet as demand outpaces production and wild stocks have declined, more attention is being paid to sustainable cultivation and harvesting methods that can keep the industry surviving.
Seaweed has a long history in South American style of cooking. The native cooking of Chile made frequent use of cochayuyo, the most abundant of the country 750 types of seaweed. Today, cochayuyo is commonly found in place of meat incharquican, a traditional dish cooked slowly in a closed pan.
Kelp, a type of large brown seaweed, as the new vegetable is a global trend too, and for good reason. Nutritionally, seaweed is packed with iodine and other nutrients, and appears on trend-making menus in Google's New York cafeteria, though it used to be thought difficult to get people to eat it.
While 83 percent of cultivated sea vegetables are produced for human consumption, we aren’t just eating it. Seaweed is used in fertilizers and animal feed, and seaweed-based food additives are likely in many products in your kitchen and bathroom right now. Carrageenan, made from red seaweed, is in everything from shampoo and toothpaste to ice cream and some hot dogs.
While seaweed grows readily—there are concerns that humans are taking too much of the wild stuff. It is possible that overexploitation of natural seaweed resources could lead to significant ecological, economic, and social consequences at local, regional, and even global scales. In Latin American countries like Brazil and Peru, where the seaweed industry is based on harvesting wild seaweed rather than cultivated, the need for environmentally friendly models is urgent.
1. What do you know about seaweed?A.It is hard to grow. | B.It is good to health. |
C.It tastes delicious. | D.It costs a great deal. |
A.How people collect weed. | B.What people do with seaweed. |
C.How people cook with seaweed. | D.Where people trade seaweed. |
A.To make the best of the seas and to increase the export of seaweed. |
B.To help more people out of poverty and to open up its new markets. |
C.To meet the needs of the market and to preserve the wild resources. |
D.To cut the costs of seaweed industry and to benefit rural population. |
【推荐2】The sunflower sea star has been listed as a critically endangered species following a groundbreaking population study led by Oregon State University (OSU) and The Nature Conservancy.
“These giant sea stars used to be easy to find and were a hit with divers. Unfortunately, your chances of finding one now are next to nothing in most of the areas near the United States—this listing is one step to extinction—and I don’t think they’re coming back without help,” said OSU’s Sarah Gravem, a research associate in the College of Science and the lead author of the study.
Populations of the sunflower sea star suffered dramatic crashes because of a marine (海洋的) wildlife epidemic event, which began in 2013. Scientists used more than 61,000 population surveys from 31 data sets to calculate a 90.6% decline in the sunflower sea stars and estimated that as many as 5.75 billion animals died from the disease, whose cause has not been determined. Moreover, the research showed no sign of population recovery in any region in the five to seven years since the event.
Sunflower sea stars are a key catcher of purple sea urchins (海胆) and the sea star decline has helped the increase in the urchin population in many regions. Too many urchins are linked to a decline in kelp forests(海藻林) already facing pressure from marine heat wave events, making the future uncertain for ecosystems that provide habitat for thousands of marine animals and help support coastal economies.
“Because most people are not out in the ocean every day, we don’t realize how much it’s being changed and impacted by humans. We need to think about how to keep our ocean healthy. While reducing the release of carbon dioxide is the most pressing need, rebuilding key catcher populations, like the sunflower sea star, can be an important piece of the puzzle too,” said study co-author Sara Hamilton, a Ph. D. candidate in the OSU College of Science.
1. What can we infer about sunflower sea stars from Sarah Gravem’s words?A.They present a danger to divers. |
B.They cannot recover on their own. |
C.They cannot adapt to the new environment. |
D.They attract many tourists to the United States. |
A.Human beings’ overfishing. |
B.The arrival of a new species. |
C.The rising ocean temperature. |
D.The occurrence of a marine disease. |
A.Their common enemies are sea urchins. |
B.Sunflower sea stars feed on the sea keep forests. |
C.Sunflower sea stars help preserve the sea kelp forests. |
D.The sea kelp forests provide habitats for sunflower sea stars. |
A.More species should be introduced to the ocean. |
B.Scientists play the most important role in protecting the ocean. |
C.The influence of human activities on the ocean has decreased since 2013. |
D.More action should be taken to increase the number of sunflower sea stars. |
【推荐3】Popping food into the microwave for a couple of minutes may seem harmless, and Europe's stock of these quick-cooking ovens give out as much carbon as nearly 7 million cars, a new study has found, and the problem is growing. With costs falling and kitchen appliances becoming frequently updated, owners are throwing many microwave after an average of eight years. This is pushing sales of new microwaves which are expected to reach 135 million annually in the EU by the end of the decade.
A study by the University of Manchester worked out the emissions of carbon dioxide-the main greenhouse gas responsible for climate change - at every stage of microwaves, from production to waste disposal (处理). “It is electricity consumption by microwaves that has the biggest impact on the environment,” say the authors, who also calculate that the emissions from using 19 microwaves over a year are the same as those from a car. According to the same study, efforts to reduce consumption should focus on improving consumer awareness and behaviour to use appliances more efficiently. For example, electricity consumption by microwaves can be reduced by adjusting the time of cooking to the type of food.”
However,David Reay, professor of carbon management argues that,although microwaves use a great deal of energy, their emissions are minor compared to those from cars. In the UK alone, there are around 30 million cars. These cars emit more than all the emissions from microwaves in the EU. Backing this up, recent data show that passenger cars in the UK emitted 69 million tons of carbon dioxide in 2015. This is 10 times the amount this new microwave oven study estimates for annual emissions for all the microwave ovens in the whole of the EU. Further, the energy used by microwaves is lower than any other form of cooking. Among common kitchen appliances used for cooking, microwaves are the most energy efficient, followed by a stove and finally a standard oven. Thus,rising microwave sales could be seen as a positive thing.
1. What is the finding of the new study?A.The use of microwaves emits more CO₂ , than people think. |
B.CO2 emissions pose a major threat to the environment. |
C.The frequent use of microwaves may do harm to our health. |
D.Quick-cooking microwave ovens have become more popular. |
A.They have a shorter life cycle than other appliances. |
B.They take less time to cook than other appliances. |
C.They are getting much easier to operate. |
D.They are becoming more affordable. |
A.Cooking food of different varieties. |
B.Eating less to cut energy consumption. |
C.Improving microwave users' habits. |
D.Using microwave ovens less frequently. |
A.It plays a positive role in environmental protection. |
B.It makes everyday cooking much more convenient. |
C.It will become less popular in the coming decades. |
D.It consumes more power than traditional cooking. |
【推荐1】A few weeks ago, I bought a locally-grown salad from a vending machine(自动售货机). But then I immediately realized that it was packaged in a plastic jar. ''I guess I live with this jar now and forever. '' I thought sadly as I stared down at my new child.
The salad jar was only the latest in a long line of examples of how I am addicted to the responsibility of reusing everything, trying to never throw anything away. Water bottles have been given second lives, and berry containers are transformed into Tupperware. I recently even looked at a plastic straw in my fruit juice: Could I reuse it too…?
Yet trying to squeeze my salad jar under my kitchen counter this weekend, I finally had to admit: Being an environmentalist has turned me into a hoarder(囤积者). While keeping a certain number of jars and vegetable bags will allow me not to buy new containers, at a certain point those 30 berry containers begin to get a bit unnecessary. Who am I kidding? Then one day I came across a blog post that asks accusingly. ''Are you turning your own home into a landfill(垃圾填埋场)? ''
In my defense, there is absolutely no excuse not to be a conscious consumer. The solution is painfully obvious, but hard to admit: Delaying waste is not, in fact, rejecting waste. In an over-packaged, over-consuming culture, this can feel like a burden. While I refuse to throw away packaging, the fact remains: I already have it. The damage is done. I've been ignoring one of the most essential and difficult parts—reduce, reuse, recycle. Even if I go out of my way to reuse the waste I do have, I need to reduce what I am bringing home in the first place.
While I might not be ready to go full zero-waste, it's a goal that is admirable to work toward. Until then, my salad jar child is going to make a great overnight oats jar.
1. What does the author try to indicate by the last sentence in paragraph 2 ?A.How important reusing is. |
B.How enthusiastic she is about reusing. |
C.How she makes use of the plastic straw. |
D.Why she is responsible for reusing plastic straws. |
A.She enjoys collecting a variety of small jars. |
B.She has saved far more containers than she needs. |
C.She likes the idea of saving fine packages in daily life. |
D.She stores more berry containers than other containers. |
A.Over-packaging. | B.Delaying waste. |
C.Over-consuming. | D.Rejecting waste. |
A.buy fewer over-packaged goods |
B.throw away unnecessary packaging |
C.reuse materials as much as possible |
D.appreciate the value of recycling materials |
【推荐2】Fisayo Longe started her fashion label Kai Collective to celebrate all female forms—not just the western idea of beauty. “I feel my clothes transform you into a woman who is more confident,” says Longe.
Born in London and raised in Lagos, Nigeria, before returning to the UK when she was 15, Longe’s original outlet for her love of fashion was her blog Mirror Me. Having a passion for travel, Longe would pick up fabrics from the countries she visited and make clothes for herself, which she posted on social media. As her creations started to become a hit, the seed for her own brand was planted.
“I wanted something I could put 100% of my creativity into, something that belonged to me and women like me,” explains the business owner, who recalls going into a high street store and the jeans not fitting her body very well.
Longe says, “I’ve always wanted to build that kind of community of women because, having grown up in Nigeria, I feel some women are made to feel they have to dim (使暗淡)their light—we don’t realize our power. Things are all centred around men and marriage. I want to build a community that focuses on ourselves and our confidence.”
With no formal fashion training, Longe set up Kai Collective four years ago with money borrowed from her mum. Longe is the first to admit she was rather “naive” when she started, giving an example of heading to Turkey with her mother to find a company to produce her designs. “That’s not the way to find producers,” she says. “It’s much better to go to trade shows.”
But whatever she’s doing, it’s obviously working, with the brand featured in an Elle magazine cover shoot with the model Adwoa Aboah, as well as in Beyonce’s black-owned businesses list.
1. How did Longe express her love of fashion at first?A.By setting up her own brand. | B.By making her clothes while travelling. |
C.By visiting high street stores frequently. | D.By putting her designs on social media. |
A.To help women realize their dreams. | B.To stress women’s role in a community. |
C.To inspire women to live independently. | D.To encourage women to find their own value. |
A.She was afraid of failure. | B.She got formal fashion training. |
C.She lacked relevant experience. | D.She hunted for producers at trade shows. |
A.She is on the right track. | B.She will never give up. |
C.She has great ambitions. | D.She is really hard-working. |
【推荐3】I’m a TV show host. One Sunday, I took my 7-year-old daughter by the sea for lunch. On arriving at the beach, I saw JoJo, a rich man in the hotel business. We sat down to chat in an open-air cafe.
Suddenly our talk was interrupted (打断) by a stranger, who politely asked permission to speak to me. Often people want to tell me something about my TV show, when I’m out on the streets.
He asked to speak to me alone, so we stood a bit away from my table. He said, “I’m James, 35 years old, father of a 7-year-old girl, who’s very sick. She needs treatment abroad. The doctors said that if she was treated in the UK, she would probably survive. But I’m poor, so can you please help me?”
Speechless, I looked at the man whose eyes were full of tears and asked how I could help. After we talked for a while, I went to sit back at the table. JoJo asked me, “What’s wrong with you? Your face changed.” I told him. JoJo was sorry for this family and said I had the means through the media to help him. Later we headed off to our destinations.
All weekend I thought about James, his daughter and his family. I even thought about doing a special TV show to raise money for this sick child.
On Monday morning I was at the office after I finished hosting my show, when my assistant said a man needed to speak to me. It was JoJo. He walked into my office. JoJo is so busy with his hotel business that I never imagined he had time to come and see me at the studios.
“Please, call the man with the sick child and tell him that I’ll pay all the money for his sick daughter’s treatment,” JoJo said, with a cheque (支票) in his hand. “I’ve been married for 35 years. I wasn’t lucky enough to have a child. I want to help this child now.” I picked up the phone to call James.
Now James’ daughter is well and living a normal life. JoJo often visit her. I’m so happy that there are so many good people on earth.
1. Why did James ask the author for help?A.He guessed the author knew many rich people. |
B.He knew that the author was a rich person. |
C.He thought the author could help him through the media. |
D.He once got help from the author. |
A.To support the author’s work. |
B.To show his love for a child. |
C.To show his sympathy for the poor. |
D.To set a good example to other rich people. |
A.Kind people are everywhere. |
B.The media are powerful. |
C.Famous hosts are always troubled. |
D.Even the richest person is not always lucky |