1 . High-resolution (高分辨率) satellite imagery has been used to map every single tree in Africa, showing a technique that could help improve the monitoring of deforestation (森林砍伐) across the world. Florian Reiner at the University of Copenhagen, Denmark, and his colleagues used images from sate lies to map canopy (树冠) across the entire African continent.

Modern sate lies usually catch tree canopies at a resolution of 30 meters — fine for measuring the size of forests, but less good at mapping individual trees. The satellite data Reiner and his colleagues used had a resolution of 3 meters, enabling the study to map all trees, including those not part of a forest.

The results suggest that 30 percent of all trees in Africa aren’t in a forest and instead are across farmland, savannah and urban areas. “Many countries in Africa lack thick forests, but have a lot of trees.” says Reiner. “These trees are extremely important to the local ecosystems, the people and the economy. By tracking every single tree, researchers can start to monitor how these trees are coping with climate change or whether they are sensitive to deforestation.” It could also improve the monitoring of reforestation efforts, which are growing in popularity as a way of removing carbon dioxide from the atmosphere.

“At a local level, being able to consistently monitor when and where trees are disappearing or reappearing can lead to more actionable insights,” says John Francis at the Alan Turing Institute in London.

“The study is a proof of concept rather than a map ready for immediate commercial use,” says Reiner. “It’s research work. It’s showing what could be done,” he says. But he is already working with colleagues to scale up the tracking approach to cover the entire global canopy: “We’re hoping that this will be seen as a way forward in monitoring tree resources.”

1. Why is high-resolution satellite imagery used to map every single tree?

A．To know the exact height of the tree.

B．To have a clear picture of the canopy.

C．To help monitor the deforestation.

D．To improve the satellite technology.

2. What is John Francis’ attitude towards the map?

A．Doubtful.

B．Disapproving.

C．Indifferent.

D．Favorable.

3. What do Reiner and his colleagues expect to do?

A．Protect the trees only in Africa.

B．Put the map into commercial use.

C．Track the entire global canopy.

D．Improve the imagery technology.

4. What is probably the best title?

A．Ways to Measure the Size of Forests in Africa

B．Coping with Climate Change by Tracking Every Single Tree

C．A Map from the Satellite Ready for Immediate Commercial Use

D．High-resolution Satellite Imagery Used in Monitoring Deforestation

2 . Fig trees are native to Europe around the Mediterranean Sea, Asia and Arica, but they can grow in much cooler climates.

Once big enough, fig trees can accept temperatures even a few degrees below freezing. Some kinds of fig trees do better in such environments than others.

Depending on the weather and pruning (修剪), a fig can grow into a bush or a tee. Bushes with several stems (茎) growing from the ground do best if covered for the winter.     1    Either way, wait until the trees have dropped most of their leaves.

One popular method for burying trees for their protection involves digging a narrow, shallow area.     2    The space should be about 30 centimeters deep, 60 centimeters wide and as long as the height of the tree. To prepare the tree, gather its branches and tie them together with soft rope.

Next, push a shovel (铲子) into the soil about a half-meter from the trunk (树干) on the side opposite the hole. Lift that side of the tree’s root ball out of the ground. Then, gently push the tree toward the hole.    3    

Pack soil around the exposed side of the roots, and around the length of the tree. Load soil over the tree. Make it at least 30 centimeters deep. You will need more soil than you removed from digging.

    4    In this case, you should work upwards from the bottom and put cloth around the tree. Then put heavy brown paper around the cloth and tie it into place. Remove some soil from around the base of the tree. Place a large piece of cardboard into the space.     5    Tie the cardboard into place.

A．And in this area the tree can be laid.

B．All kinds of the trees could use protection.

C．You can also cover, or wrap, the tree instead.

D．And bend it around the bottom part of the tree.

E．When it is lying fat, cover the tree with plastic.

F．Trees with a single trunk can be buried or covered.

G．Remove the cover on the tee on a cloudy day in early spring.

3 . Flower scents (香味) help pollinators (传粉者) locate their favorite plants. Scientists have established that air pollutants change those scents, throwing off the tracking abilities of such beneficial insects as honeybees. But new lab experiments are the first to confirm that one pollinator, the tobacco hawkmoth, can quickly learn that a pollution-changed scent comes from the jasmine tobacco flower that the insect likes.

Chemical ecologist Markus Knaden and colleagues focused on one pollutant-ozone, the main element in smog. In the lab, his team blew an ozone-changed scent from a tiny tube into a tunnel, with a moth (飞蛾) awaiting at the far end of the tunnel. Usually, when the moth smells the unchanged scent, it flies upwind and uses its long, skinny mouthparts to probe the tube the way that it would a flower. The researchers expected that the changed scent might throw the moth off a little. But the insect wasn’t attracted at all.

In addition to scent, tobacco hawkmoths track flowers visually, so Knaden’s team used the feature, along with a sweet snack, to train the moth to be attracted to a pollution-changed scent. The researchers wrapped a brightly-colored artificial flower around the tube to trick the moth back across the tunnel, despite the unfamiliar scent. And the team added sugar water to the artificial flower. After a moth was given four minutes to taste the sweet stuff, it was attracted to the new smell when sent into the tunnel 15 minutes later, even when neither the sugar water nor the visual signal of the artificial flower was present.

This study focused on only one moth species, but Knaden’s team is now working on planning experiments with other pollinators that are easier to follow than tobacco hawknoths. While he guesses honeybees might also be as adaptable as the moth was, that won’t be true of every pollinator. “The situation can become very bad for insects that are not as clever or cannot see that well. I don’t want the take-home message to be that pollution is not a problem.”

1. What does the underlined word “probe” in paragraph 2 mean?

A．Surround.

B．Favour.

C．Access.

D．Examine.

2. According to the passage, ________.

A．not all moths were attracted to ozone-changed scent as expected

B．the current research conducted by Knaden is pioneering and wide-ranging

C．not all pollinators are adaptable to human-driven changes to their environment

D．the moth didn’t like the new smell without sugar water and artificial flower

3. What’s Knaden’s attitude towards the finding of the study?

A．Positive.

B．Cautious.

C．Unclear.

D．Critical.

4. What does the text mainly talk about?

A．A moth can be rid of the tracking ability to locate its favourite plants.

B．A moth is able to establish a relationship between pollution and scents.

C．A moth may outsmart smog by learning to like pollution-changed scent.

D．A moth is born with an ability to adapt to the changes in the environment.

4 . Most of Florida is a flat peninsula (半岛) with water on three sides and houses built as close to the shoreline as possible. For one thing we are more frequently the target of hurricanes than any other state; for another, our geography makes us more easily to be hurt by rising seas.

A news story about climate change in Florida popped up. Historically, scientists believed mangroves (红树林) didn’t live farther north than Cedar Key, in the middle of Florida’s Big Bend. But that’s not the case anymore. Samantha Chapman, a biology professor who’s been studying how Florida’s mangroves have been migrating (迁移), found them up near the St Mary’s River, which forms the border between Florida and Georgia. It seems that they soon be marching through Georgia and becoming a thriving new component of coastal habitats.

But a coastal biologist named Blair Witherington took issue on the matter. The mangroves weren’t spreading into a new territory, he pointed out. They were entering areas that had been classified as saltmarsh (盐沼), where the landscape was dominated by cordgrass. Saltmarsh and mangrove create very different habitats that attract a very different set of animals. “When one community replaces the other, this diversity is lost,” Witherington remarked. Changing the animals’ habitat has the potential to influence the whole food chain, making a widespread difference.

What was driving this? “Mangroves can survive a short freeze, but not a prolonged, hard freeze. By combing through the weather records kept by the state’s orange juice industry, biologists have been able to document that Florida is having fewer prolonged hard freezes than it used to. Then the mangroves have adapted by expanding their range.” Samantha explained.

“They’ve adapted in another way, too. Not only are the mangroves spreading into areas that once were unfriendly to them, but they have also changed their life cycle to speed things up. Normally it takes them about 15 years of growth before they start making seeds. Now, as they get into these marshes, they’re producing seeds when they’ re only a couple of years old,” Samantha said.

The problem with having too many mangroves by the sea is that climate change may overwhelm them. A study by the US Geological Survey said sea level rise could wipe out mangroves all along the Florida coast. So, here’s the question we humans have to consider: Nature is finding ways to adapt to how we’ve changed the climate. What are we doing to adapt to it? Or at least slow it down?

1. What can we learn about the state of Florida?

A．It could be affected by high tides easily.

B．Its geography fuels shipbuilding industry.

C．Its houses are built in a high-lying but flat area.

D．It is often hit by tornadoes and suffers huge losses.

2. What is the news story about Florida’s mangroves?

A．They migrate to warmer regions.

B．They are marching into a new habitat.

C．They form the border between Florida and Georgia.

D．They are introduced into Florida to prevent flooding.

3. Which of the following would Blair Witherington agree with?

A．Saltmarsh is fragile and requires urgent protection.

B．Florida includes a rich diversity of natural habitats.

C．The benefits of the mangroves outweigh their troubles.

D．Everything in the ecosystem is connected complicatedly.

4. What are the 4th and 5th paragraphs mainly about?

A．What mangroves had to face in their habitats.

B．Whether mangroves had influence on other plants.

C．How mangroves adapted to the changing environment.

D．Why mangroves had a different life cycle in marshes.

5. What can we infer from the last paragraph?

A．Human beings are supposed to worship nature.

B．It is urgent to grow more mangroves along coastlines.

C．Measures against mangroves’ migration are far from enough.

D．What we should do to stop the climate change is still up in the air.

5 . He was wandering in a rice field of dreams.     1     After walking a while he lay down in the leaf-shade with a friend, quite hidden. A rest was a good idea, because the wonder-plants went on and on. In fact, they covered the world.

Then Yuan Longping woke up, laughing.     2    . But they still deserved their name of super rice. The leaves were straighter and taller than ordinary, and the grains plumper. They had all the vigor of the wild strain that he and his team had found after much searching and had cross-bred, over careful years, with the domesticated variety.

The figures spoke for themselves.     3    . In Yunnan province more than 17000 kilograms had been produced per hectare. China’s rice crop had risen from 57m tonnes in 1950 to 195m in 2017; from food deficiency, to food security. Higher rice-yields allowed farmers to turn more land to other uses-fruit, vegetables, fishponds-so that people ate more and well.

For this he won the Medal of the Republic, China’s highest, and the World Food Prize. An asteroid was named after him. There was talk of the Nobel, too.     4    . Though he was rich, from his shares in a seed company that used his name, he looked like a peasant, thin as a twig, with his face leathered by sun and his big hands rough from “playing in the mud” all day.

He was far happier in his short-sleeved work-shirts, out in his rice, or stripped off swimming in any wild river he could find, than in a tang suit in some conference hall.

A．Nothing but the continuous development of his beloved country seemed to attract him

B．With his new hybrid rice the annual yield was 20-30% higher, so at least 60m more people could be fed every year.

C．His dreams focused on his people and his country, where all enjoyed food and wealth.

D．All that seemed just smoke to him.

E．The plants were taller than men. Each grain is as big as a peanut.

F．The rice plants he had tended for decades at Anjiang and then Changsha, sowing and nurturing them, visiting daily on his motorbike to inspect them, were not quite there yet.