2 . Walk through the Amazon rainforest today and you will find it is steamy, warm, damp and thick. But if you had been around 15,000 years ago, during the last ice age, would it have been the same? For more than 30 years, scientists have been arguing about how rainforests like the Amazon might have reacted to the cold, dry climates of the ice ages, but until now, no one has reached a satisfying answer.

Rainforests like the Amazon are important for mopping up CO₂ from the atmosphere and helping to slow global warming. Currently the trees in the Amazon take in around 500 million tons of CO₂ each year: equal to the total amount of CO₂ giving off in the UK each year. But how will the Amazon react to future climate change? If it gets drier, will it still survive and continue to draw down CO₂ ?

Scientists hope that they will be able to learn in advance how the rainforest will manage in the future by understanding how rainforests reacted to climate change in the past. Unfortunately, getting into the Amazon rainforest and collecting information are very difficult. To study past climate, scientists need to look at fossilized pollen, kept in lake mud. Going back to the last ice age means drilling deep down into lake sediments （沉淀物）which requires specialized equipment and heavy machinery. There are very few roads and paths, or places to land helicopters and aeroplanes. Rivers tend to be the easiest way to enter the forest, but this still leaves vast areas between the rivers completely unsampled（未取样）.So far, only a handful of cores have been drilled that go back to the last ice age and none of them provide enough information to prove how the Amazon rainforest reacts to climate change.

3 . When the leaves begin to change their colors and the birds head south, we know the season is starting to change. On September 7 comes White Dew (白露), the 15th solar term (节气) of the year. It indicates (标志着) the beginning of the cool autumn. As the temperature falls, white dew is often seen on the grass and trees at night.

For w riters and poets, autumn is a difficult season to describe. It ’s the end of the summer, and therefore a little sad. The days seem to get shorter, and when you wake in the morning, t here’s mist(薄雾) and it’s cooler. Winter is just around the corner.

American writer Ernest Hemingway wrote in his book A Moveable Feast (《流动的盛宴》), “You expected to be sad in the fall. Part of you died each year when the leaves fell from the trees and their branches (枝条) were bare (光秃秃的) against the wind and the cold, wintry light. ”

But on the other hand, autumn has its good side. There are so many changes at this time of year, such as the colorful leaves and cooler nights. French w riter Albert Camus even thought autumn was a second spring,   “when every leaf is a flower.” This view is also found in the most famous autumn poem in English literature, To Autumn by John Keats. In that poem, Keats says that autumn has its own songs, just like spring.

Another theme of this season is wisdom (智慧). The arrival of autumn is thought to be similar to a person becoming mature (成熟的).

The great Irish poet W.B. Yeats used this idea in his poem The Wild Swans at Coole (《库尔的野 天鹅》), writing about the changing seasons in Coole Park in the west of Ireland. Seeing and counting 59 swans, he remembers first making the count as a young man. Seeing the swans do the same thing for all those years, he’s reminded (提醒) that even though we get older, our hearts always stay the same age.

4 . Cities are diverse ecosystems. In addition to visitors from the wild, such as coyotes (丛林狼) in Los Angeles or boars (野猪) in Berlin, a large number of species share our urban areas. As our cities spread, we need to think about what it is like for other species to have human neighbors.

Because cities are built for humans, they do not always provide suitable habitats for wildlife. For example, most city parks are kept neat and tidy so that humans will find them beautiful. But when we cut grass or plant flowers, we destroy natural habitats.

Our actions sometimes help other species. When a bridge in Austin, Texas was repaired, engineers added small gaps running along the length of its bottom. This made a good home for bats, and soon the bridge was the home of thousands of bats. At first, people were afraid of the bats and tried to get rid of them. Now, they have come to value their winged neighbors. The bats are a tourist attraction, and they eat lots of bugs every night.

There are also structures built with the aim of bringing wildlife into the city. The Beijing Olympic Forest Park is a good example. The park used native plants and created open, natural spaces for wildlife. The result is a zone in Beijing with over 160 species of birds. In many ways, the park is the opposite of a zoo. Instead of being kept in cages, wildlife can move about freely.

Another example is a 2011 proposal for a tall “Birdscraper” building in New York. The building is intended to protect birds and fight pollution at the same time. It would be in the middle of a lake, birds would sit on it, and their droppings would fall into the water. The droppings would help water plants grow well and then create oxygen through photosynthesis (光合作用). If we learn to share our space, we can become better neighbors to the wildlife around us. If we do not, more species will become extinct and our own future will be endangered.

5 . Habitat loss, pesticides (农药) and climate change are threatening insect populations worldwide. In 2019, Biological Conservation reported that 40% of all insects species are declining (减少) globally and that a third of them are endangered.

And while it may sound nice to live in a world with fewer bad insects, environmental writer Oliver Milman says that human beings would be in big trouble without insects. That’s because insects play important roles in pollinating (给……授粉) plants we eat, breaking down waste in forest soil and forming the base of a food chain that other larger animals including- humans-rely upon.

“It would be an extremely terrible place to live in—and certainly not something we should ever aim for,” Milman says of an insect free existence. “You would certainly have mass starvation and social unrest…It’d be a place where there would be smelly waste and dead bodies everywhere because insects that break down those materials would be gone. ”

Milman charts the troubling decline of insects in his new book, The Insect Crisis: The Fall of the Tiny Empires That Run the World. He says that while it’s impossible to know exactly what’s happening with every insect species in the world, the overall trends are not good: The butterfly population in North America has declined quickly in the past 40 years, for example, and a U. N. assessment done in 2019 found that half a million insect species are under threat of extinction, some in the coming decades.

“The world, our surroundings, would be far quieter, far duller without insects,” he says. “When you start kind of digging down into these figures looking at the research, it’s clear that there’s something seriously wrong…There is a straight decline in most insect populations, and that spells major trouble for them but also for us.”

7 . My daughter has been crazy about raising a pet for a long time.

Last spring I bought two small chickens for her. She got _________ and took good care of them._________,a few days later, both chickens died. She _________ into tears because of their death. I helped her _________ the two chickens under a tree behind our house. I thought it would be the _________ of her idea. 

However, I was wrong. Children are children after all. The failure hasn’t _________ my daughter in any way. She still tried to keep a small animal or even a snail. 

One day last winter, I _________ under the eaves (屋檐) of the house a family of sparrows. My daughter and I could _________ the sparrows as our “pets”, but we didn’t. 

So I told her to _________ the grains on the windowsill (窗台). A few minutes later, the sparrows came to land on the windowsill __________ and pecked (啄) at the rice. Suddenly my daughter asked me, “Mum, can we catch and cage the sparrows, and let them live with us in the room? How __________ it is for them to live outside!” 

“Oh, my dear, I do not think it’s a good idea. You know,” I explained to her. “The sparrow is a bird who loves __________.No one can keep them in a cage. If they are caught, they will die quickly. They are __________ to living outside. Moreover, they have a warm nest under the eaves.” 

From then on, we have set up a kind of relationship with the sparrow family. We feed them and __________ them as pet birds. However, we do not need to possess them. We __________ seeing these little birds flying and jumping among branches, leaves and flowers in the spring morning.

9 . If the three Rs (reduce, reuse and recycle) is a guideline to save the planet, garbage-sorting is where the   efforts start. Since May 1, Beijing has started to carry out mandatory garbage-sorting in new efforts to better protect the environment. Under the new regulation, residents are required to classify household waste into four categories: kitchen, recyclable, hazardous and other waste. People who fail to sort their garbage properly can be fined from 50 to 200 yuan, reported Xinhua.

Some residential communities in Beijing have introduced rewards to encourage residents to sort their garbage. According to Xinhua, residents can earn points by classifying their domestic waste correctly and then exchange the points they accumulate for daily necessities such as soap.

Garbage sorting practices have reached over 70 percent of housing estates in 18 cities, including Shanghai,     Xiamen and Hangzhou, according to the Ministry of Housing and Urban-Rural Development. Shanghai first enacted a mandatory garbage-sorting regulation in July 2019 and has had a 90 percent compliance (服从) rate among its housing estates.

According to a report by the Ministry of Ecology and Environment, over 90 percent of the public believe that garbage-sorting is important for the protection of the environment. However, garbage-sorting is still a big problem in China. Only 30 percent of participants said they think they are completely sorting their waste, the report noted. According to Xinhua, it’s partly because many people lack the willingness to sort their own waste. Also, some previous garbage regulations didn’t include fines for people who failed to obey them.

“It’s a must to have a legal guarantee to promote garbage sorting,” Liu Jianguo, a professor from Tsinghua University, told China Daily, “Aside from China, many countries like Germany, Spain and Britain, also ask people to sort waste into specific categories. In Japan, there is a fixed time for the sorting of each kind of garbage and littering.”

10 . They give us paper and fuel, as well as vital ecological services-like cleaning the air, storing carbon and providing habitat. We’re talking about trees, of course. But human changes to the environment largely appear to be causing profound transformations in trees around the world.

In a new study, scientists reviewed global research on trends in tree seedlings (籽苗), growth and death. They combined those data with an analysis of deforestation. And they found that worldwide, older trees are dying at a higher rate than in the past due to factors like rising air temperature, wildfires, drought and pathogens (病原菌).

“And most of the drivers of that decrease in large, old trees are increasing themselves, such as temperature is going up, droughts are more severe, wildfires, windstorms and deforestation are all on the increase—although variable across the globe — they’re generally increasing. And so for both the loss has already occurred, but we expect more continued loss of big, old trees,” said Nate McDowell, an earth scientist at Pacific Northwest National Lab, who was one of the study’s authors.

“So if we have an increasing rate of death, particularly of the larger, older trees, what’s left are the younger trees. So that’s why, on average, through the loss of bigger, older trees, our forests are becoming naturally younger and shorter.”

This is a problem, because old trees are vitally (至关重要) important.

“For sure, the increase in death does limit the carbon storage (储存) of an ecosystem and can force the system to become a carbon source to the atmosphere. The second reason we care is from a biodiversity (生物多样性) perspective (角度): Old trees tend to house a higher biodiversity than young forests do. And another reason is beauty: As a society, we care about these trees. We have national parks named after these big trees. So there’s a personal reason for people to care about this as well.”