2 . Each year, the world produces more than 300 million tons of plastic waste, which can take a longtime to breakdown. Almost a third of the world’s plastic waste is polypropylene, a hard plastic used to make bottle: caps and food containers that typically take hundreds of years to degrade.

Now, a group of scientists at the University of Sydney, in Australia have developed a solution: using fungi (真菌) found in soils to devour lab samples of polypropylene.

In the experiment, the scientists first weakened pieces of polypropylene plastic by exposing them to heat, chemicals, or ultraviolet (UV) light so the fungi can do their job quickly. Fungi degrade materials like plastic into simpler molecules that they can then get rid of. The usually smooth plastic become full of marks as the fungi carryout their dirty work.

The two fungi, Aspergillus terreus and Engyodontium album, made a meal of the plastic in the lab experiments. As the researchers reported, between 25 and 27 percent of samples were digested after 90 days, and the plastic was completely broken down after 140 days.

More than 400 microorganisms have so far been found to degrade plastic naturally, with fungi attracting a fair bit of attention for their ability to degrade all sorts of man-made materials. “Recent studies suggest some fungi may even degrade some of the ‘forever chemicals’ like PFAS, but the process is slow and not yet well understood,” explains microbiologist Dee Carter of the University of Sydney.

Currently, the team is testing ways to speed up the degradation process, and assessing the economic and environmental factors of potential commercial use. If the team can transform their laboratory solution into a commercial-scale plastic waste management system, the world will finally have a promising solution to one of our most pressing environmental issues.

3 . Scientists have discovered more than 5,000 new species living on the seabed in an untouched area of the Pacific Ocean that has been identified as a future hotspot for deep-sea mining, according to a review of the environmental surveys carried out in the area.

It is the first time the previously unknown biodiversity of the Clarion-Clipperton Zone (CCZ), a mineral-rich area of the ocean floor that spans 1.7m sq miles between Hawaii and Mexico in the Pacific, has been comprehensively documented. The research will be critical to assessing the risk of extinction of the species, given contracts for deep-sea mining in the near-pristine area appear imminent.

Most of the animals identified by researchers exploring the zone are new to science, and almost all are unique to the region: only six, including a carnivorous sponge and a sea cucumber, have been seen elsewhere.

Contracts for mining exploration in the CCZ have been granted to 17 deep-sea mining contractors in an area covering 745,000 sq miles. The companies, which are backed by countries including Britain, the US and China, want to dig for minerals including cobalt manganese and nickel in part to sell to the alternative energy sector.

To better understand the impact of mining this fragile ecosystem and its newly discovered inhabitants, an international team of scientists has built the first “CCZ checklist” by compiling all the records from expeditions to the region. Published in the journal Current Biology, it includes 5,578 different species, of which an estimated 88% to 92% had never before been seen.

To study and collect specimens (样品) from the ocean floor, biologists have joined research cruises in the Pacific that send remote-controlled vehicles to traverse (穿越) the seabed 4,000 to 6,000 meters below. Adrian Glover, a deep-sea biologist at the NHM and senior author of the study described it as an “incredible privilege”. The expedition, funded through the Natural Environment Research Council and others, is backed by UK Seabed Resources (UKSR), a deep-sea mining company that operates the UK’s exploration area. The scientists watch operations by video link direct from the boat as new species are gathered by remote control vehicles in the darkness below.

The seabed, Glover said, is an “amazing place” where, despite the extreme cold and dark, life thrives. “One of the characteristics of the abyssal plain is the lack of food, but life has a way of persisting down there,” he said, “It’s a mystery.” One of the deep-sea animals discovered was nicknamed the “gummy squirrel”, because of its huge tail and jelly-like appearance, he said. There are also glass sponges, some of which look like vases.

With approval for deep-sea mining looming, Glover said he believed it was “imperative that we work with the companies looking to mine these resources to ensure any such activity is done in a way that limits its impact upon the natural world”.

4 . Have you ever heard of and seen Canadian geese? Do you know that they __ fresh grass and seeds?

Canadian geese have a good __ for their politeness. They always bow down to you whenever you walk by. However, I have recently found that they can sometimes be __ to their peers, especially on occasions when they quarrel for food——yes, these __ gentlemen do quarrel, just for something to eat

Yesterday I witnessed two Canadian Geese arguing __ for a clump(草丛) of beautiful fresh grass. The clump was __ right in the middle of them, while the two were shouting noisily, stretching their necks as long as they could to look aggressively at each other. It’s __ to witness the “impolite” side of Canadian geese. Hence, I couldn’t help __ my morning walk, standing still to watch these “gentlemen” quarreling. Interestingly, after a short while, a truck roared past their feast, disturbing their __ conversation. The two geese were equally __ by the massive “monster”, thus giving up their conversation.

Would they start quarreling again? I stood still, __ the ridiculous question and waited. Beyond my expectation, right after the truck’s passing by, the two geese immediately lost their ___for quarreling as if they had forgotten all about what had happened. Even the two turned around and left the __ in opposite directions as if nothing had happened. They left only me there, imagining what might have happened without the __.

They got along harmoniously again. Sometimes it’s not that bad to be __.

5 . It could be said that trees naturally call for attention as they climb toward the sky with their arms outstretched. Yet, it’s still easy for us to ignore them. As we rush through our own day-to-day lives, trees seem to play the role of an insignificant backdrop.

Nothing could be further from the truth. Rooted to a single spot, trees appear sill.But that stillness is not associated with laziness. In fact, trees are guards of the planet as the impact of their hard work carries miles farther than the ground in which they stand.

Globally, trees are the most cost-effective tool in promoting biodiversity. They support the survival of a significant number of animals. For example, a big reason why ring-tailed lemurs (狐猴) are endangered is that half of the forests they depend on in Madagascar off the East coast of Africa were cut down.

Not only do animals depend on trees for shelter, trees are significant to the health of humans as well. In fact, doctors in Canada are so convinced of trees’ benefits for the mind and body that they recommend patients visit national parks. Trees help a lot in tackling climate change too. They absorb and store carbon dioxide(CO2) — the key greenhouse gas emitted by our cars and power plants — before it has a chance to reach the upper atmosphere and trap heat around the Earth’s surface.

So it’s time to put trees in the spotlight. The Arbor Day Foundation, the world’s largest nonprofit, is devoted to this exact mission: inspiring people to plant,protect, and honor trees. We know there’s never been a more important time for trees. And we know there’s never been a more important time for mankind to engage in its role as environmental guards. This isn’t a one-sided relationship. What we give to nature we will receive in return, tenfold (十倍地). So as springtime arrives once again, take a moment and appreciate what a tree can be.

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9 . Rachel Carson’s classic best seller about ecological threats, Silent Spring, started a wave of American environmentalism. It played a direct role in the 1972 decision to ban the use of the pesticide(杀虫剂)DDT. Sixty years ago, the public was introduced to Carson’s arguments. The coming anniversary makes this a good time to consider whether the book achieved one of her major goals: protecting wildlife and, in particular, birds.

Carsen took a complex technical subject — the damaging effects of persistent pesticide and expressed it in one simple, poetic image: a spring in which no birds sang. She asked us to imagine what it would be like to awaken in the morning in a world without these songs. She wrote with grace, and she made us feel the loss. But how well have we acted on Carson’s warnings?

With some exceptions, we haven’t been very successful, and neither have birds. Twenty-nine percent of North American birds have died out since 1970, Grass lands were the hardest hit, with a documented loss of more than 700 million breeding individuals. The number of dead birds totaled nearly three billion, a figure that sparked(引起) a campaign with tips on what people can do to save them. Given these data, it is easy to conclude that despite the brilliance of her writing, Carson did not succeed in protecting birds.

Still, the 2019 bird study, despite its worrying results, also suggests that protecting biodiversity is not lost cause. One important exception is wet lands, where bird abundance increased by 13 percent. The other animative exception is bald eagles, which acre on the edge of extinction at the time Carson wrote, but they recovered in large part as a result of the ban on DDT. A news story published by the Au dub on Society notes that “the numbers show that taking steps like wildlife management, habitat restoration and political action can be effective to save species.”

10 . Yellow flower carpeted fields are a sure sign of summer. In Denmark alone, more than 200,000 hectares of rapeseed (油菜籽) are planted every year. But until now, the plant has only been used for oil and animal food, as it is both bitter and unsafe for human consumption.

To protect themselves, the rapeseed plants produce a group of substances (物质) called glucosinolates (硫苷), which give the plants a strong and bitter taste that scares off insects and disease. As a result rapeseed is unhealthy to eat and the rapeseed cake, which is the remains of the seeds after the oil has been squeezed out, has only been used as feed for pigs and chickens, despite its 30 — 40 percent protein content.

Now, researchers from the University of Copenhagen have discovered the three proteins that help to store the bitter substances in seeds of thale cress (阿拉伯芥), a plant closely related to the rapeseed. The new knowledge makes it possible to prevent the accumulation (积聚) of these substances in the seed by removing the proteins through “transport engineering” technology. In doing so, the defensive substances remain in all other parts of the plant, allowing it to continue to defend itself.

So far, the researchers have shown that their method works in thale cress. “The next task is to apply our method to the closely related rapeseed plant, which we are now working on,” says Professor Halkier, leader of the research.

“Half of plant proteins in the EU come from rapeseed. The climate crisis demands that we reduce meat consumption and eat more plants, which is where rapeseed has great potential as a new source of plant protein. Our latest research results bring us a step closer to making full use of rapeseed,” says Professor Halkier.