2 . Since the first factories began manufacturing polyester (聚酯) in the 1950s, humans have produced about 9. 1 billion tons of plastic. And about 12 percent has been burnt, releasing harmful gases into the air. Most of the rest has ended up in landfills and in the natural environment. Plastic inhabits the oceans, cities and national parks, in large or tiny pieces.

Carbios is among the companies that are attempting to commercialize a type of chemical recycling, which breaks down polymers into their fundamental moleculars, called monomers (单体). Those monomers can then be recombined into polymers that are as good as new.

But some experts warn that chemical recycling may face many of the same issues that already plague the recycling industry, including competition from cheap plastics made from the raw materials. For the past several years, Carbios has been improving a method that uses an enzyme (酶) found in a microorganism to convert polyethylene terephthalate (PET), a common ingredient in plastic bottles, into its monomers.

Enzymatic recycling’s promise isn’t limited to PET: the approach can be applied to other plastics. In early experiments, it took weeks for enzymes to process just a part of a batch of PET. In 2020, Alain Marty, chief science officer at Carbios, announced they’d developed an enzyme that could stand warmer temperatures and change nearly an entire batch of PET into monomers in a matter of hours.

Most PET produced globally is used for textile fibers, which, because they often contain mixed materials, are rarely recycled. Mats Linder, leader of Stena Recycling in Sweden, said he’d like to see recycling technologies focus on these and other parts of the recycling industry where conventional recycling is coming up short.

As it happens, Carbios is working to do just that. Gregg Beckham, a senior research fellow at the National Renewable Energy Laboratory, believes the global plastic problem will call for a diverse mix of technological solutions. He thinks enzymatic recycling and other recycling technologies are advancing rapidly, and he’s optimistic that they’ll have a role to play.

3 . As most parts of the country enter the summer flood season, weather events will again put the country’s disaster preparedness to test.

Some areas in the south of the country are experiencing what the National Meteorological Center calls the strongest rainfall in 60 years. Other parts of northwestern and central China, as well as the Yellow and Huaihe river valleys, have been under the control of heat waves.

On Sunday, the Ministry of Water Resources and the China Meteorological Administration issued the year’s first red alert for flash floods. On Monday, the National Meteorological Center sustained red alerts for high temperatures, yellow alerts for storms and fog, and blue alerts for severe convective (对流) weather.

According to experts, this round of strong rainfall will be long-lasting, wide-ranging and of very strong intensity (强度) in some areas. The waters in 75 rivers across the country have already risen above the warning levels.

As the lessons from the past few years have taught us, climate change has considerably increased the frequency, intensity and damaging potential of extreme weather events. And, most worrisome of all, their severity has frequently made people victims before they know it.

The upsetting potential of severe weather would still be beyond most people’s imagination had it not been the 2021 floods in Zhengzhou, capital of Henan province. It exposed the consequences of poor urban planning, inadequate drainage systems, inactive disaster preparedness and slow emergency responses.

The importance of multi-hazard early warning systems and natural disaster response preparedness was highlighted in the sixth Assessment Report that the UN Intergovernmental Panel on Climate Change released in August 2021.

The report provided evidence that extreme hydrometeorological events, such as droughts, floods and heat waves, are increasing as is the severity of their impacts on everyday life around the globe as well as harming fragile ecosystems. It concludes that climate change is widespread, rapid and intensifying, and extreme weather will become more frequent.

4 . Shocking declines in bird populations are taking place around the world. Loss of natural habitats is cited as the key threat to bird biodiversity. Climate change is identified as a possible driver of bird population declines.

“We are now witnessing the first signs of a new wave of extinctions of continentally distributed bird species,” says lead author Alexander Lees, senior lecturer at Manchester Metropolitan University in the United Kingdom. “Bird diversity peaks globally in the tropics and it is there that we also find the highest number of threatened species.”

The study says about 48% of existing bird species worldwide are known or suspected to be undergoing population declines. Populations are stable for 39% of species. Only 6% are showing increasing population trends, and the status of 7% is still unknown. The study authors reviewed changes in bird biodiversity using data from the International Union for Conservation of Nature’s   “Red List” to reveal population changes among the world’s 11,000 bird species, The findings mirror the results of a 2019 study which determined that nearly 3 billion breeding birds have been lost during the past 50 years across the United States and Canada.

Despite their findings, study authors say there is hope for bird conservation efforts, but transformative change is needed. “The fate of bird populations is strongly dependent on stopping the loss of habitats,” says Lees. “That is often driven by demand for resources. We need to better consider how commodity (货物) flows can contribute to biodiversity loss and try to reduce the human footprint on the natural world.”

“Fortunately, the global network of bird conservation organizations taking part in this study have the tools to prevent further loss of bird species and abundance,” adds Rosenberg. “From land protection to policies supporting sustainable resource-use, it all depends on the will of governments to live side by side with nature on our shared planet.”

As a human in the 21st-century industrialized world, there’s a good chance that microplastics are pumping around in your veins(静脉), as indicated by a small first-of-its-kind study in Environment International.

According to a report on the study, scientists from Vrije University Amsterdam recently developed a method to    1     (accurate) measure concentrations of microplastics in human blood for the first time. Just as     2    (suspect) in the past, microplastics from the outside world are ending up in the bloodstream of humans. The team tested the blood of 22 people and concluded that 17 of the samples contained tiny amounts.

“Up to now, we    3    (prove) plastic exists in our bloodstream,” study author Marja Lamoree said. “This dataset is the first of its kind and must be expanded    4     (gain) insight into how widespread plastic is in our bodies, and how    5    (harm) that may be. With this insight, we can determine whether    6    (expose) of our bodies to microplastics poses a threat to health.”

Human bodies are riddled(充斥)with microplastics,    7     wider evidence for the effects of microplastics    8    human health is still inadequate. However, with    9    large number of studies finding that microplastics can be found in our bodies, it’s a question    10    needs some definite answers soon.

6 . A method to transform a commonly thrown-away plastic to a resin (树脂) used in 3D- printing could allow for making better use of plastic waste.

A team of Washington State University researchers developed a simple and efficient way to transform polylactic acid(PLA), a bio-based plastic used in products such as plastic tableware and food packing to a high-quality resin. Yu-Chung Chang, a postdoctoral researcher on the work said they made stronger materials just straight out of waste, and they hoped that would provide people with the stimulation to upcycle this stuff instead of just throwing it away.

PLA is rarely recycled because like most plastics, when it’s melted down and reformed, it doesn’t perform as well as the original version and becomes less valuable.

“But once you look into it, it turns out that it can take up to 100 years for it to break down in a landfill,” Chang said. “In reality, it still creates a lot of pollution. We want to make sure that when we start producing PLA millions of tons, we will know how to deal with it. ”

In their study, the researchers developed a fast method to recycle PLA breaking the long chain of molecules (分子) down into simple monomers (单体)-the building blocks for many plastics. The entire chemical process can be done at mild temperatures in about two days. The chemical they used to break down PLA, aminoethanol, is also inexpensive.

“If you want to rebuild a Lego castle into a car, you have to take it apart brick by brick, Chang said. “That’s what we did.” Once PLA was broken down to its basic building blocks, the researchers rebuilt the plastic and created a type of liquid resin that is commonly used as printing “ink” for 3D printers. When used in a 3D printer and cured into plastic pieces the product was equal or better than commercially available resins.

The researchers have applied for a temporary patent and are working to further improve the process. They are also looking into other applications for the upncycling method.

Scientists are racing to study the volcano in Tonga that    1     (erupt) just before sundown on January 15,2022.

“Everything so far about this eruption is really strange,” said Janine Krippner,    2     scientist working on Smithsonian’s Global Volcanism Program. “The sound of the explosion, the tsunami(海啸) waves that followed eruption and the huge energy of this explosion,    3    equaled to five to six million tons of TNT, were unlike any seen in recent     4    (year).”

The tsunami waves that followed the eruption    5     (be)even stranger. Tsunami waves usually start from the center of the eruption. Yet this time, waves appeared in other places far earlier than would be expected of a classic tsunami.     6    addition, as tsunami waves travel further, they usually become    7    (weak).While the waves that hit the islands in Tonga were damaging, they weren’t high enough to account for the surprisingly larger waves across the ocean.

Monitoring underwater volcanoes is a complex task. GPS — which is frequently used     8    (track) changes in the surface-doesn’t work on the seafloor. The situation in Tonga shows how well the Tonga Geological Services(TGS)has been applied to    9    (deal) with the latest eruption. “They don’t have a huge amount of money. They don’t have a number of staff, either.” Janine Krippner added. “But     10    (actual) they have done a really nice job to reduce the possible.

Inside the world of Buy Nothing

David Stahl did not need leftover(剩下的) pickle juice(腌黄瓜汁). But a few months ago, he decided     1    (ask) for some just to see if it was possible, posting a request to a New York chapter of Buy Nothing, a local Facebook group.

It turns out, people are willing to give away just about anything, if you ask. A week     2    (late), Stahl walked 10 blocks to a stranger’s apartment lobby and retrieved(取回) a 1-gallon Mt. Olive jar of the pale green liquid.

Welcome to the wild world of Buy Nothing, a network of social media groups, mostly on Facebook,     3     people give and receive things, treating the stuff     4    (take) up space in their homes as gifts meant to be shared and treasured.     5    (create) in 2013 by two women in Bainbridge Island, Washington, it has grown to 6,700 independent Buy Nothing Facebook groups in 44 countries.

Giving away the stuff that you no longer want     6    (be) nothing new. But Buy Nothing turns the act of decluttering(清除杂物) into a way to meet and befriend your neighbors. Because each group is     7    (geographical) limited, sometimes encompassing(包含) only a few city blocks,     8     active group can become a tightknit(紧密联系的) trading post.

“We have plenty right here within each of our local communities to sustain(支援) us,” said Liesl B. Clark, one of the     9    (found) of the Buy Nothing Project. “If we can reuse and refurbish and fix and repair and just keep recycling these items, nothing needs to     10    (discard)(丢弃).”

10 . Large amounts of waste, or garbage, are filling streets in Nepal’s capital, Kathmandu, after protesters blocked a road leading to a landfill outside the city. People in Bancharedanda where the garbage is kept blame the government for not doing enough to protect them from the waste.

One British tourist, Richard McSorley, recently talked about the problem. He remembered how clean Kathmandu was when he first visited it many years ago. “If I were a new tourist, I would be despondent now,” McSorley said, while pointing to a load of garbage next to a city street. For weeks, treatment of waste has been a continuous problem in the city surrounded by hills. The problems started after people in the village of Bancharedanda refused to have the garbage thrown at a nearby landfill.

Biswas Dhungana was one of the protesters. He said the villagers were refusing to permit trucks loaded with garbage to enter. They say government officials have done little to provide basic equipment and effective ways to deal with the garbage. He added, “We have been forced to live like pigs in terrible conditions for several years as the government has not done anything to keep the village clean.”

Last week, hundreds of villagers built a wall of rocks on the road leading to Bancharedanda. It forced about 200 trucks filled with Kathmandu’s garbage to return without dumping their load. It was said that protesters also threw stones from surrounding hills.

Sunil Lamsal is an official to watch over how Kathmandu’s garbage is treated. He said, “I am working to deal with the concerns of the locals in Bancharedanda. But now, garbage continues to grow on the streets of Kathmandu. This has led to increased danger for people living in the capital. In the light of it, the government will soon take further positive measures to tackle the problem, as the environment affects every family.”