2 . Chemists have spent the past century trying to make plastics break down in seawater. Most plastics take centuries to fully break down in the ocean.     1     However, this may change. Scientists have designed a new kind of plastic that can break down in seawater within weeks, not decades or more.

    2     It is known as polylactide (聚乳酸) or PLA. It’s made by linking many building blocks into a long string. Scientists had hoped PLA would quickly break down in the environment. And in some places it does, but not in seawater. After three years in the ocean, LA remains largely unchanged.

Timo Rhein Berger is a PhD student at the University of Twente in the Netherlands.     3       For part of that work, he became part of a team that just added some biology-inspired breaking points to PLA. They put those breaking points to places where monomers (单体) in the PLA molecules are linked. Then, they soaked (浸泡) their samples in artificial seawater. In this way, they measured how fast the PLA broke down. As the team had hoped, seawater attacked the weakened links between monomers. That could tear the PLA chain apart.     4    

When the researchers weakened 15% of PLA’s monomer links, the PLA broke down entirely within just two weeks. When they weakened only 3% of the links, the breakdown took about two years.     5     This can be achieved by adjusting how many weakened links it has.

In 2016, Shennongjia made     1     onto the UNESCO World Heritage List. It meets two criteria     2     (require) by the list. Firstly, it is apparently one of the most “complete” natural     3    (area) in the world,     4     some plants and animals have survived millions of years. Secondly, Shennongjia     5     (have) incredible biodiversity. It is     6    (challenge) to look after so many species. But scientists make great efforts     7    (protect) them. The local people also play an important part, and they live     8     harmony with nature.

Nina has run marathons in 32 countries. All of her runs have a guiding purpose: to call attention     1     global water issues. Nina recently finished her year-long series of runs in Chicago,     2     thousands were attending a water conference.She called for action     3    (address)the struggles of people around the world     4    (face) “too little water or too dirty water”. Her efforts have encouraged others to take part by running through a global campaign called“Run Blue”.

6 . Ways to Cut Your Carbon Footprint

Your carbon footprint, which drives more global warming, is associated with everything from powering our homes to getting around, producing our food and making all the stuff we buy. There are dozens of things we can do to cut our carbon footprint.

Reduce food waste. About one-third of all food gets wasted each year. Producing food that won’t be eaten wastes valuable resources, including energy. It also creates a lot of greenhouse gases. Someone could cut their food carbon footprint by 12 percent by not wasting purchased food.    1    

    2    Most U.S. electricity comes from a mix of sources, including fossil fuels. Unless a home is fully powered by renewable sources, such as wind and solar, people will need to use less electricity to cut their energy carbon footprint.

Jacket your home with insulation (隔热材料). When it’s chilly out, a thick jacket holds in our body heat to keep us warm.    3    Thick insulation in the walls, roofs and floors keeps heat inside in winter and outdoors in summer. Roughly four in every five U.S. homes would save energy costs and cut greenhouse gas emissions if they added more insulation.

    4     People who use traditional vehicles can make up the largest part of the carbon footprint. That’s why people should walk more, ride bikes or take mass transportation. If you need to use a car, consider an electric vehicle (EV). Once they hit the roads, EVs don’t emit planet-warming gases.

Buy less new stuff. Everything we buy also contributes to our carbon footprints. So a key way to shrink those footprints is to buy fewer new things. Shopping for the secondhand goods cuts much pollution.    5     And recycle wherever you can.

9 . When Malaika Vaz was a kid, living in Goa, India, she was constantly surrounded by nature. Among her childhood experiences, she recalls journeys to the Arctic and Antarctic, climbing mountains, diving, and windsurfing.

At some point in her late teens, Vaz realized adventure didn’t really mean anything if there wasn’t an intention to protect the natural spaces we were exploring in. Motivated by her passion for filmmaking, she began to seek a way that would both satisfy her appetite for adventure and allow her to advocate the protection of the species and ecosystems she interacted with.

Today Vaz wears many hats in the filmmaking world, as a documentary director, producer, and presenter. After falling in love with manta rays (蝠鲼), she discovered they were being hunted illegally and started to dress herself as a seafood trader to get as close as possible to the issue. She traced sellers to figure out why the threatened species were being killed. She shared the shocking details in Peng Yu Sai, her Green Oscar-nominated film on the matter.

The subjects that grab her attention, Vaz admits, run the gamut. When she was asked to define her focus, she replied that she preferred variety. She always argues that the issues she looks into are more interrelated than they may initially appear. “I think that it’s exciting to dive into the different aspects of environmental stories,” she says.

Her work doesn’t stop at recording important stories; she also ensures the message is heard. From Vaz’s viewpoint, real improvement in planetary protection lies in the hands of each of us rather than just those of several environmentalists. “If you’re an engineer and you care about the natural world, you can change the kind of construction materials you use. If you’re a teacher loving nature, you can bring that into the learning for your class.” she says.

As a filmmaker, Vaz believes it’s important to figure out ways that attract the audience who can push for the protection of the natural world.

10 . Compost (堆肥) is one of the most wonderful things in the world. You take organic matter that would otherwise end up in landfills and create a nutrient-rich material that will help make gardens grow, flowers bloom and make it easier to feed the world. Thanks to Tipa, an Israeli start-up, you will soon be able to add plastics to your compost mix.

Plastic is one of the most challenging problems on the planet. As No Camels reports, it often takes 500 years for plastic to break down, and even then, microplastics remain in water or on land. Furthermore, according to Inc. Com, even though plastic can theoretically be recycled, less than 5 percent of flexible plastic packaging that is put into recycling by consumers is actually recycled.

But that doesn’t need to be the case anymore.

Now, Tipa and other companies have begun to create plastics that are able to biodegrade like any organic matter does. When asked how she got the idea of creating compostable flexible plastics, Dafna Nissenbaum, the CEO and co-founder of Tipa, said, “Nature also packs its products, like bananas, apples and oranges, but with a compostable material. Our plastics will break down exactly like any other organic material and turn into solid fertilizer (肥料).”

Unlike other compostable plastics on the market, Tipa’s plastics can be fully composted in home composts. This means that the average person with a garden compost could use their packaging and just throw it in the compost instead of the recycling bin when they are done with it.

Another thing that Tipa has been doing is to create partnerships with existing producers instead of creating their own factories. The company’s materials are purposefully designed to be compatible (兼容的) with machinery that already exists and produces non-compostable plastics. Tipa says that fits in with its goal of creating a sustainable future.

Tipa has partnered with some high-end designers. Both Stella McCartney and Mara Hoffman use Tipa’s products to package their products. Many brands are now aware that using sustainable packaging will endear them to customers, and Tipa helps them do that.