1 . Over eight million acres of land in the US were scorched in 2020. We've lost more trees faster than nature or humans can regenerate. So we've got to have better tools to be able to reforest faster.

A Seattle—based company called DroneSeed thinks that tool could be, as its name suggests, automated seed dropping drones, which means multiple drones operating to perform a task at the same time.

Typically, reintroducing tree growth is a slow, manual process that can take up to three years. It requires growing young trees in a nursery that tree planters plant by hand. And they're using a shovel and they burn the caloric equivalent of running two marathons every day. But automated drones can cover a lot more ground and get the job done faster.

Grant Canary, DroneSeed CEO, says in groups of five, the drones can cover up to 50 acres in a day compared to about two acres by human. And he says the speed and automation can save landowners 30 to 50 percent of their reforestation costs. Eight- foot- long drones take off on pre-programmed routes carrying loads of nearly 60 pounds. They zip up and down those mountainsides, distribute seed vessels in very targeted, precise locations and make reforestation workable. But they don't drop raw seeds. Instead, Drone Seed has developed seed vessels that include a patent mixture of every thing a seed needs to survive, like fertilizers, nutrients and natural pest deterrents.

Unlike seedlings, they don't need to be buried in the ground. The vessel is a dry fiber so it absorbs moisture, soaking up and expanding so that helps it avoid drying out, which is one of the biggest causes of seed mortality.

Aerial seeding is not a new idea. But historically, raw seeds are dropped and can land in poor soil. So Drone Seed uses advanced laser mapping to identify the best locations for their seed drops, targeting healthy soil and other ideal conditions. Those are the areas that are not gravel. They don't have high competitive vegetation and so the seeds themselves are going to grow better.

2 . In recent years, Ethiopia has become a regional leader in solid waste management. Last year, the country transformed the landfill (垃圾填埋场) in Addis Ababa into a new waste-to-energy plant, the first such project on the continent. The plant incinerates up to 1, 400 tonnes of waste every day, about 80 percent of the city's rubbish, supplying the capital with 25 percent of its household electricity needs.

However, despite these important steps, challenges remain in Ethiopia. Although the country has permitted the Basel, Stockholm and Rotterdam conventions, laws and policies for environmentally sound management of hazardous (有害的) wastes are still not effective in pre- venting littering waste illegally.

To help Ethiopia meet these challenges, the Chemicals and Waste Management Program is supporting the country with a three-year project to enhance its capacity for sound management of hazardous wastes.

In the initial stages, a project management unit will be formed, made up of many representatives from government departments and private organizations. This unit will be responsible for reviewing and assessing Ethiopia's current legal system, which, despite numerous advances in recent years, does not specifically target the recycling of hazardous waste. Once legal gaps are identified, the project will seek to update existing policies and strategies.

Many people in Ethiopia are not aware of the possible effect of environmental damage and the need to report such crimes to the police. To resolve this pressing issue, Ethiopia will be conducting a series of capacity-building activities, including creating awareness-raising programs, training trainers and providing equipment.

Ethiopia will also work to establish a national mechanism for chemicals and waste management by engaging government departments and civil society groups. Authorities will also make budgetary provisions (预算拨款) in national, regional and institutional planning to ensure funding for these activities is sustainable even after the project's completion.

3 . The Indo-Pacific bottlenose dolphins of Shark Bay in Western Australia have an unusual way of obtaining food.

They drive fish into a large, empty marine gastropod shell. Then they carry the shell and captured(捕捉)fish up to the surface, and shake it upside down. Then, the fish go straight down into the dolphins' stomachs. It's called shelling, only the second tool use recorded among dolphins, and the first that dolphins have been seen learning from their friends, just like great apes.

The dolphins were first observed using tools over 20 years ago, slipping sea sponges over their beaks(喙)to protect them as they searched for food. This behaviour is called sponging, and it allows the dolphins to access food in deeper water channels than non-sponging dolphins.

Sponging is a skill passed down from mothers to daughters-a type of learning called vertical transmission. But there is another kind of learning, horizontal social transition, in which individuals pick up skills from their social peers-their friends.

There are similarities between dolphin and great ape societies that have led scientists to believe that dolphins should be capable of horizontal leaning.

Now a team of researchers led by behavioural ecologist Sonja Wild of the University of Konstanz in Germany has finally identified it.

Their data comes from over a decade's worth of observations. Between 2007 and 2018, the researchers documented over 1.000 individual dolphins across nearly 5,300 encounters with the animals.

They used genetic, behavioural and environment data to model the likely transmission pathways, and found that shelling was likely spread among friends, rather than passed down from parents.

This opens the door to a new understanding of how dolphins may be able to behaviourally adapt to changing environments.

In 2011, a large marine heatwave destroyed the seagrass habitat of Shark Bay, in which the dolphins search for food. This resulted in a die-off of both fish and the invertebrates that live in the giant shells that the dolphins use for their fishing, and, afterwards there was an immediate increase in the dolphin's shelling behaviour. It's possible that both the decrease in fish and the increase in shells could have played a role in this uptick.

5 . With a quick movement, the little creature vanishes in the air like it never existed and somehow appears dramatically-this is a part of the film Fantastic Beasts and Where to Find Them. But in reality, “disappeared” fantastic creatures can also reappear.

The Global Wildlife Conservation(GWC) announced on Oct 30 they have rediscovered the Voeltzkow's chameleon(变色龙)in Madagascar. The last time that the animal was seen was in 1913.

This discovery excited the researeh team, but the finding was not easy. The GWC organized an expedition as part of its Seareh for Lost Species program, an attempt to rediscover species that have not been observed by scientists for at least a decade. They headed into the forests of northwestern Madagascar in April 2018. But they didn't have much luck for a long time. Just days before the trip was to end. the tour guides spotted one of the chameleons. Ultimately, the team discovered three males and 13 females.

Male Voeltzkow's chameleons are up to 164 millimeters long and are light green with dark stripes, which get darker when they are angry or stressed. Females are smaller than males, growing to about 150 millimeters long. They can change their skin to a pattern of red dots and a stripe of purple against a background of black and white.

“The Voeltzkow's chameleon adds color and beauty to the planet, and reminds us that even when all seems lost, a great adventure can reawaken hope." said Don Church, president of the GWC. "Now we have so much to learn about this extraordinary reptile(爬行动物)・including how we can best save it from extinction.”

This isn't the only time a species thought to be extinct has been rediscovered. In fact, this year scientists discovered a frog that has been missing for more than 50 years in a Brazilian jungle. Another example is the Albany adder snake, which was rediscovered in 2016. The species had disappeared for over a decade and was generally believed to be extinct.

So how are these "lost" species able to make a comeback? If the environment changes in favor of certain species that have been considered extinct, the population size of those species may recover again. As they reach greater numbers, the chance of humans discovering them increases.

6 . Happiness is not a warm phone, according to a new study exploring the link between young life satisfaction and screen time. The study was led by professor of psychology Jean M. Twenge at San Diego State University (SDSU).

To research this link, Twenge, along with colleagues Gabrielle Martin at SDSU and W. Keith Campbell at the University of Georgia, dealt with data from the Monitoring the Future (MtF) study, a nationally representative survey of more than a million U. S. 8th-, 10th-, and 12th-graders. The survey asked students questions about how often they spent time on their Phones, tablets and computers, as well as questions about their face-to-face social interactions and their overall happiness.

On average found that teens who spent more time in front of screen devices — playing computer games, using social media, texting and video chatting — were less happy than those who invested more time in non-screen activities like sports, reading newspapers and magazines, and face-to-face social interactions.

"The key to digital media use and happiness is limited use," Twenge said. "Aim to spend no more than two hours a day on digital media, and try to increase the amount of time you spend seeing friends face-to-face and exercising — two activities reliably linked to greater happiness."

Looking at historical trends from the same age groups since the 1990s, it's easy to find that the increase of screen devices over time happened at the same time as a general drop-off in reported happiness in U. S. teens. Specifically, young peopled life satisfaction and happiness declined sharply after 2012. That's the year when the percentage of Americans who owned a smartphone rose above 50 percent. By far the largest change in teens' lives between 2012 and 2016 was the increase in the amount of time they spent on digital media, and the following decline in in-person social activities and sleep.

8 . Traffic jams are the horrible dreams of motorists’ lives. If you think your journey is bad, spare a thought for drivers in Sao Paolo, Brazil — one evening in May last year, the traffic jams during the rush hour added up to a 344km queue, according to the city's traffic management agency.

This isn't a new problem, of course. During the car boom of the 1960s, city planners had one seemingly obvious solution: build more and wider roads. But the more roads created, the more cars they attracted. So what's the solution? Some cities have adopted easy methods, like banning cars from driving on certain days.

However, ending this horrible dream may need more of a complete rethink. A company, Urban Engines, has a slightly fresher method. "We're providing an online game that offers trip suggestions and prizes to encourage commuter behaviour changes, including changing travel from peak to off-peak times,“ says Shiva Shivakumar, Urban Engines' co-founder and GEO. For the past two-and-a-half years, the company has conducted pilot studies in major cities, including Bangalore and Singapore. In Bangalore, one-in-six people who took part in the trial started travelling off-peak, and in Singapore one-in-eight.

But others think this solution doesn't go far enough—and that we should provide more reasons for putting fewer cars on the road. “The only effective long-term solution is to improve alternative methods—walking, cycling and particularly high-quality public transport,” says Todd Litman of the Victoria Transport Policy Institute in Canada. Road pricing that charges motorists extra if they drive during the rush hour could also be an option. Cities like Singapore, London and Stockholm have successfully used road pricing to control the steel river.

The solution to beating traffic jams in cities, if it comes, will probably take a long time to gain prizes. But if at least some of these new ideas are a success, the days of Sao Paolo's heavy traffic jams may finally become history.

10 . They' re not the world' s tallest or longest bridges, but a string of river crossings made from tree roots are engineering wonders that contain lessons for modern architects.

The town of Cherrapunji in the Khasi Hills is credited with the world record for annual rainfall of over 75 feet! And in this rainy, wet climate, the rubber fig tree grows with abandon. The tree has a secondary root system that grows up above the ground floor and lets the tree easily grow on top of big stones and even out in the middle of streams. Long ago, the Khasis, a tribe in Meghalaya region, realized they could make use of these roots to their own advantage. By controlling and directing the secondary roots, they have created strong living bridges with which to cross streams and rivers by themselves.

To make a tree grow in a certain direction, the tribespeople use the trunks of a betel nut tree whose middle is got rid of, as a guidance system. The thin, tender roots of the rubber tree are placed so they grow in the direction of the tree trunk rather than fanning out. Eventually, the roots reach the other side of the river and grow into the soil. This process can take well over a decade before the bridge is fully functional and then over time the bridge grows and strengthens. Rocks are placed along the bridge' s sides to improve the footpaths.

Some of these bridges are over 100 feet long and can even support the weight of fifty or-more people at a time. These bridges are used daily by the people of the villages around Cherrapunji and a few are thought to be more than 500 years old. There is even a double decker bridge , known as the “Umshiang Double-Decker Root Bridge", which features two bridges grown right on top of each other. It is thought to be the only bridge of its kind.