3 . In 1999, Giuliana Furci, founder and founding director of the Fungi (真菌) Foundation, developed a deep interest in fungi. They were everywhere, and the 20-year-old took particular joy in the variety of mushrooms: small and button-shaped; tall and umbrella-like; round with red caps topped with white flakes. Some were commonly found in people’s diets, for they were rich in nutrients such as vitamin, fiber, minerals and protein.

But Furci also quickly realized that these fungi went largely ignored in Chile, where there were few guidebooks and an almost total lack of policies and resources to protect them from over-harvesting and other human activities. Determined to correct this, Furci wrote a field guide and set up the Fungi Foundation—a nonprofit dedicated to fungi conservation. In her guide, special attention went to the role of fungi in the ecosystem.

“Life on the planet wouldn’t exist without fungi,” said Greg Mueller, a mushroom conservation expert. “Because of their relationship with forests and trees, we can’t survive without fungi. In terms of the health of the planet, they’re incredibly important to humans and the overall ecosystem.” Fungi can break down plants and animals, thus cycling nutrients and increasing their availability in the soil. They are also important contributors to the soil carbon stock through the same process. What’s more, fungi have been found to help degrade (降解) various pollutants, such as plastic. And mycelium (菌丝体), which is the root structure of mushrooms, is now being used to replace unsustainable materials, such as plastic and animal-based products.

Because of these, exploration of fungi was expanded at a faster pace. However, some were already listed as critically endangered. In 2010, Furci took an even bigger step—with other environmental nonprofits, she put forward a proposal for the government to systematically assess how large new developments such as housing, dams, and highways affect fungi. In 2012, a law was passed and Chile became the first country in the world to protect fungi by law.

4 . There are two distinctive types of electric buses making their way along Nanjing Xi Lu, one of Shanghai’s busiest roads. The first is a fleet of blue trolleybuses that serve bus route number 20, a line set up by a British-run transport company in 1928. They use poles to receive electricity from wires overhead and have kept the route running in this way for nearly a century. But while the historic electric buses are a reminder of Europe’s past technological innovation, the new buses traveling alongside them are symbols of China’s contemporary net-zero ambition. These modern electric buses powered by lithium batteries (锂电池) , were introduced in Shanghai in 2014. They offer a smoother ride, especially during starts and stops. Widely used across China, these buses are key to the country’s EV transition and are influencing the global shift towards green transportation.

The most recent data available shows that China in 2018 was still the second largest source of carbon dioxide emissions in the global transport sector, responsible for 11%, and behind only the United States, which accounted for 21%. After around two decades of government support, China now boasts the world’s largest market for e-buses, making up more than 95% of global stock. At the end of 2022, China’s Ministry of Transport announced that more than three-quarters (77% or 542, 600) of all urban buses in the country were new energy vehicles. The speed of this transition was remarkable.

So far, however, the Chinese cities with the most successful e-bus introduction — such as Shenzhen, Beijing and Shanghai — all have moderate weather and are relatively flat. To take its e-bus campaign to the next level, China faces challenges. For one thing, it is difficult to bring fleets to cities such as Hong Kong, which — like London — have double-deckers. These two-storeyed vehicles are “very hard” to electrify, because they are heavier, use more energy, and so need bigger batteries, reducing the number of passengers they can carry. Cold weather is a problem, too, as it can make a battery’s charging time longer and its range shorter. The reason China has not achieved 100% electrification for its buses is its northern regions, which have cold winters, says Xue Lulu, a transportation expert at the World Resources Institute China.

5 . If you haven’t taken down your Christmas tree yet, no worries. Here’s an idea: have you ever thought about eating it?

Julia Georgallis has some recipes. Over the last five years, she’s been preparing carefully for Christmas dinners in London with a friend. “How can we make something sustainable around Christmas time? What can we cat? What’s the thing that no one eats and that somehow represents Christmas? And then we just decided on Christmas trees,” Georgallis says.

She turned it into a book, How to Eat Your Christmas Tree. And her idea is that it’s not that odd. Some people enjoy Christmas wine. Some people like to go shopping and most people can get behind saving the planet.

“What I aimed for this book to do, really, was to get people thinking about the odd ways that they can be more sustainable in their daily lives,” Georgallis says.

“Eating Christmas trees isn’t going to save any animals in danger or freeze any ice caps. But if we start to think about everything that we do as a whole, then that builds up, you know, and that helps,” she says.

Most of the recipes in her book use the needles from the tree. “You’d use the needles like a herb,” she says.

“And different Christmas trees kind of have different flavors. They’re quite subtle, but they do have different flavors. So fir (冷杉), which is a really popular choice of Christmas trees, gives people better feeling and atmosphere. And then you have pine, which is a little bit more delicate.”

A warning: some Christmas trees are poisonous if eaten — like cypress and cedars. And be sure your tree wasn’t sprayed with pesticides (杀虫剂) and other chemicals. “So if you have any doubt that your Christmas tree might not have been grown to eat, then maybe don’t eat it,” Georgallis says.

And, of course, don’t even think about eating your artificial tree!

So, with all those instructions and with the appropriate tree, what could we cook? Well, Georgallis’ book has all sorts of recipes for different foods and drinks. Let’s open up the world’s cuisine with simple ingredients!

7 . Researchers in Australia have identified enzymes (酶) in the body of certain beetle larvae (甲虫幼虫) that can degrade or break down plastic. In a study published in Microbial Genomics, they write that these “superworms” could help reduce plastic waste in the future.

“Superworms are like mini recycling plants, cutting up the polysyrene (聚苯乙烯) with their mouths and then feeding it to the bacteria in their stomach,” said Chris Rinke from the University of Queensland in Australia. “The breakdown products from this reaction can then be used by other microbes to create high-value chemicals.”

In the study, scientists divided beetle larvae into three groups, feeding one group wheat bran, one polystyrene and one nothing. Over three weeks, they monitored their growth. “We found that superworms fed a diet of just polystyrene not only survived, but even had marginal weight gains,” said Rinke. “This suggests the worms can get energy from the polystyrene, most likely with the help of their stomach bacteria.”

On the other hand, the plastic-fed worms gained much less weight and were overall much less healthy than the bran-fed ones, though better off than the starvation group. After three weeks, some larvae were also set aside to grow into beetles, according to the study. About 93% of the bran-fed larvae formed adult worms, while about 67% of the plastic-fed larvae and 10% of the starved larvae formed adult worms.

The researchers investigated the superworm’s stomach bacteria to find the specific enzymes linked to plastic degradation, writes Fionna M. D. Samuels for Scientific American. The enzyme that degrades the polystyrene appears to live with the stomach bacteria, not the worm itself.

Polystyrene is one of the most common plastics used today. But it’s not very chemically reactive, and breaking it down with industrial recycling methods takes high heat. So, researchers have been looking for plastic-degrading enzymes and bacteria for years.

Further research will still need to be done to figure out how to employ these worms, bacteria and enzymes in recycling facilities.