1 . Increased human activity and climate change have caused a rise of algae (藻类植物) in water bodies around the world—sometimes choking ecosystems of sunlight and oxygen. In more extreme cases, they can produce dangerous poisons that can sicken or kill people and animals. But the plenty of algae could prove crucial as our population rises beyond eight billion people worldwide because algae are crops that don’t need land, freshwater, or fertilizer to fill nutritional gaps.
And even though they are so closely associated with human’s bad impact on Earth, algae could also play vital roles in slowing climate change and helping fight against pollution, viruses, and more. With microplastic pollution documented in almost all habitats related to water, a study showed that algae can help filter microplastics from water. Algae can also filter chemicals that can be used for fertilizer.
Algae can produce more effective biofuel than traditional sources. Rescarchers at a German algae growing facility are already using it to fuel plane. Researchers believe this and other sustainable fuels could reduce carbon released from airplanes by up to 80 percent.
Animal feed containing a kind of red algae reduces harmful methane(甲烷)released from cattle by more than 80 percent. The addition works by changing the environment in a cow’s stomach, stopping the production of methane before it can be released.
Red algae can stop the copies of some viruses, and have been shown to stimulate the body’s immune (免疫的) system and could become a powerful anti-HIV medicine.
In 2019, freshwater algae were launched into space to change the CO2 breathed out by astronauts on the International Space Station into oxygen. Since algae are also high in protein, they could replace up to 30 percent of astronaut food in the future.
1. What can we know about algae from the first paragraph?| A．Better late than never. | B．Every coin has two sides. |
| C．All is well that ends well. | D．Two heads are better than one. |
| A．They avoid climate change. | B．They absorb pollutants in the air. |
| C．They reduce microplastics in the water. | D．They filter most poisonous chemicals. |
| A．Change animal feed into methane. |
| B．Store carbon released from airplanes. |
| C．Help researchers to create traditional sources. |
| D．Create biofuel and reduce methane in cows’s stomach. |
| A．By helping fight against diseases. | B．By increasing human’s strength. |
| C．By producing more oxygen than other plants. | D．By replacing much food for astronauts. |
2 . Forests are feeling the heat. In places like the American West, rising temperatures and drought mean less water for trees. Now, scientists have found that thinning early in forest growth creates tougher trees that can endure climate change. What’s more, these thinned forests can suck carbon out of the air just as fast as thick forests.
“When it comes to carbon storage and climate change adaptation, we can have our cake and eat it too,” says Andrew Larson, forest ecologist and author of the new study. “It’s a win-win.”
As trees grow, they convert carbon dioxide to food and store it in their leaves, trunks, and roots. But if trees get too crowded, they compete for light and water. Removing some trees can ease the competition, letting the remaining trees grow big and healthy. But scientists worry that removing trees can reduce forest carbon storage.
To see whether the climate trade-off truly exists, scientists tapped into a long-term experiment in northwestern Montana. In 1961, U.S. Forest Service officials started the experiment in a young forest of western larch. The forest was broken up into plots. In some plots, the 8-year-old trees were thinned from tens of thousands per hectare down to 494 per hectare. These trees grew thick trunks and broad tree shades. Other plots were left alone, and the trees there grew tall and skinny as they competed for sunlight. The original study was rooted in an interest in growing timber rapidly. But the scientists at the University of Montana sprouted a new question: How did tree density (密度) influence carbon storage?
To find out, they measured tree height, diameter, and width of branches to estimate the amount of carbon stored. They also calculated the carbon contained in other plants, dead wood, and forest floor debris. The research showed total carbon was nearly the same in both forests. The un-thinned forest had more trees, but the thinned forest compensated with bigger trees.
1. What is scientists’ finding about forests?| A．The tougher trees in thinned forests stand climate change. |
| B．Thinned forests have as much carbon as thick forests. |
| C．The American forests are suffering sever heat wave. |
| D．The thick forests grow rapidly than thinned ones. |
| A．We are able to produce and enjoy a cake together. |
| B．Carbon storage and climate stability are the final goals. |
| C．We can choose between carbon storage and climate change. |
| D．Carbon storage and climate adaptation can be achieved meanwhile. |
| A．Through observing forests grow. |
| B．Through comparative experiments. |
| C．By providing examples to illustrate. |
| D．By collecting massive amounts of data. |
| A．To achieve how to plant trees scientifically. |
| B．To test how much carbon forests contain. |
| C．To prove the advantages of thinned forests. |
| D．To see how tree density affects carbon storage. |
Herbal tea has v
1. Why does the woman want to plant vegetables?
| A．To save money. | B．To sell fresh food. | C．To try something new. |
| A．The lack of gardening skills. |
| B．The limited room for gardening. |
| C．The time to clean the backyard. |
| A．Purchase some seeds. |
| B．Check out a website. |
| C．Ask neighbors for help. |
5 . Now, a study proves that gardens are more than just a pretty place. The study, by researchers at Illinois State University, demonstrates that such constructed gardens can have a measurable and positive impact on water quality.
Floating gardens are essentially platforms built and wrapped in coconut husks (椰子壳), and filled in with native plantings. As plants grow, they extend their roots into the water. On the North Branch of the Chicago River, non-profit Urban Rivers and its partners are developing a mile-long floating eco-park called the Wild Mile. The re-development of this former industrial canal is Urban Rivers’ important project. As part of the park, floating gardens, attached to shore, are being fixed.
The primary aim of the floating gardens is beautification. But the Illinois State team, from the University’s Department of Geology, Geography, and the Environment, saw an ideal setup for a controlled experiment. “We joined it because it’s the perfect opportunity to see if there’s an influence on water quality,” explains lead author Abigail Heath.
The study is novel: previous studies have explored floating gardens’ influence on water quality over time, primarily in wastewater treatment ponds, but not over space, in moving water. The project also matches well with Urban Rivers’ broader goals. “The city is interested in bettering water quality,” says Phil Nicodemus, Urban Rivers’ Director of Research. “Happily, Illinois State took part in it later.”
Could this small human-made park improve water quality? An average of data collected over the course of the study shows middle but definitive improvement. For example, nitrogen (氮) dropped from 4.69 milligrams per liter in surface water to 4.43 milligrams per liter, a drop of about 1 percent.
“Despite how small this garden was, there was measurable improvement in water quality from upstream to downstream,” notes Heath. She and her colleagues see this as a model for how large floating gardens should be to help improve water in similar settings. “Even this tiny garden makes a difference,” she says.
1. What can be inferred from the second paragraph?| A．The floating gardens are environmentally friendly. |
| B．The floating gardens are fixed everywhere in the eco-park. |
| C．The floating gardens can help fix the former parks. |
| D．The Urban Rivers were once industrial canals. |
| A．To reduce waste water. | B．To attract more visitors to the park. |
| C．To make the surroundings brilliant. | D．To help researchers do the experiment. |
| A．The floating garden. | B．The project. |
| C．The treatment of ponds. | D．The quality of water. |
| A．Floating Gardens: More than Pretty |
| B．The Best Way to Better Water Quality |
| C．A Practical Method of Improving Parks |
| D．Floating Gardens Beautify the City |
Space Station Rice Tests Show Promise
Chinese astronauts have successfully grown rice seedlings (幼苗) onboard the Tiangong space station.
There have been other rice
China launched the Wentian space laboratory into orbit on July 24. The space lab, which weighs 23 metric tons and is 17.9 meters tall, is the country’s
“We want to investigate how microgravity affects the plant flowering time on the molecular (分子的) level
“If we want to land on and explore Mars, food
7 . With no special equipment, no fences and no watering, two abandoned agricultural fields in the UK have been rewilded (重新野化), in large part due to the efforts of jays, which actually “engineered” these new woodlands. Researchers now hope that rewilding projects can take a more natural and hands-off approach and that jays can shed some of their bad reputations.
The two fields, which researchers have called the New Wilderness and the Old Wilderness, had been abandoned in 1996 and 1961 respectively. The former was a bare field, while the latter was grassland—both lay next to ancient woodlands. Researchers had suspected that the fields would gradually return to wilderness, but it was impressive to see just how quickly this happened, and how much of it was owed to birds.
Using aerial data, the researchers monitored the two sites. After just 24 years, the New Wilderness had grown into a young, healthy wood with 132 live trees per hectare, over half of which (57%) were oaks. Meanwhile, the Old Wilderness resembled a mature woodland after 39 years, with 390 trees per hectare.
“This native woodland restoration was approaching the structure (but not the species composition) of long-established woodlands within six decades,” the researchers explained in the study.
Part of this reforestation was done by the wind, and researchers suspect that previous ground disturbance may have aided the woodland establishment—which is good news, as it would suggest that agricultural areas may be reforested faster than anticipated. However, animals—Eurasian jays, thrushes, wood mice, and squirrels—also played an important role in helping the forests take shape. This handful of species provided much of the natural regeneration needed for the forest to develop. Jays, in particular, seem to have done a lot of heavy lifting.
1. What does the underlined word “shed” in Paragraph 1 refer to?| A．Be opposed to. |
| B．Be ashamed of. |
| C．Get used to. |
| D．Get rid of. |
| A．The scale of the woodlands. |
| B．The diversity of the fields. |
| C．The rate of the changes. |
| D．The frequency of the wilderness. |
| A．The woodland restoration was approaching the structure of long-established ones. |
| B．Much of the wilderness of the fields was owed to birds. |
| C．Previous ground disturbance aided the woodland establishment. |
| D．How quickly the fields returned to wilderness over time. |
| A．The essential role of humans in the reforestation. |
| B．The factors that contribute to the reforestation. |
| C．The importance of woodland establishment. |
| D．The threats faced by a handful of wild animals. |
8 . For many people, catching a smell of freshly cut grass is a pleasant sign that warmer weather is here to stay. For the grass, however, this scent signals an entirely different story.
The smell we associate with freshly cut grass is actually a chemical SOS, one used by plants to beg nearby creatures to save them from attack. After all, when danger strikes —whether it's gardening equipment or a hungry caterpillar — plants can't lift their roots and run. They must fight where they stand. To protect themselves, plants employ a string of molecular (分子) responses. These chemical communications can be used to poison an enemy, warn surrounding plants of dangers or attract helpful insects to perform needed services.
Clearly, plants can communicate. But does that mean they can feel pain? According to some researchers, plants release gases that are the equivalent of crying out in pain. Using a laser-powered microphone, researchers have picked up sound waves produced by plants releasing gases when cut or injured. Although not audible to the human ear, the secret voices of plants have revealed that cucumbers scream when they are sick, and flowers cry when their leaves are cut.
There's also evidence that plants can hear themselves being eaten. Researches show that plants understand and respond to chewing sounds made by caterpillars dining on them. As soon as the plants hear the noises, they respond with several defense mechanisms.
For some researchers, evidence of these complex communication systems — giving out noises via gas when in pain — signals that plants feel pain. Others argue that there cannot be pain without a brain to register the feeling. Still more scientists infer that plants can exhibit intelligent behavior without possessing a brain or conscious awareness.
As they grow, plants can change their paths to avoid obstacles or reach for support with their tendrils (卷须). This activity comes from a complex biological network distributed through the plants' roots, leaves and stems. This network helps plants reproduce, grow and survive.
1. What does the smell of freshly cut grass signal?| A．Warmer weather. | B．Being poisonous. |
| C．Cry for help. | D．The need of services. |
| A．By giving out gases. | B．By changing the color of their leaves. |
| C．By producing audible sound waves. | D．By sharing it through the root systems. |
| A．Their tendrils. | B．Their biological network. |
| C．Their communication systems. | D．Their conscious awareness. |
| A．Do plants feel pain? | B．How plants protect themselves? |
| C．Do plants communicate? | D．How plants grow and reproduce? |
