A new group of free employees have been added to a French workforce. So far, a theme park in western France         1     (employ) six birds, more exactly six crows, to collect and deal with garbage — mainly cigarette ends and other small pieces. The birds take the     2     (collect) trash to special bins where they can receive bird food in exchange     3     putting away the litter.

Park president Nicolas said, “The purpose of employing the crows is to educate people to take up their social     4     (responsible). Since the birds are able to do     5     we are much more able to do than them, we should do this by ourselves?

Crows have long been observed for their various amazing     6     (display) of intelligence. They are one of the     7     (smart) groups of animals on earth, with remarkable problem solving, tool making, and deductive (演绎) reasoning skills.

In addition to inspiring humans to pick up trash, the clever crows currently     8     (work) at the park are pretty excited to put their intelligence to work.

“It has become     9     exciting game for them” Nicolas says. “They pick up the trash on the ground, and every day they     10     (reward) for what they have done.”

2 . The battery pack of an electric vehicle (EV) powers the car hundreds of kilometers, again and again, without letting off gases. But when the battery comes to the end of it’s life, its green benefits fade. If it ends up buried, it can release poisonous materials including heavy metals.

That's just one of the emerging problems challenging researchers: how to recycle millions of EV batteries. Current EV batteries "are really not designed to be recycled" , says Thompson, a researcher at an institution.

It wasn't much of a problem when EVs were rare. But now the technology is taking off. Governments realize this is an issue and are inching toward requiring some level of recycling. In 2018, China drew new rules to promote the reuse of EV battery parts. The European Union is expected to finalize its first laws this year. And in the United States, several states, including California—the nation's largest car market—are exploring their own rules.

Recycling won't be easy. Batteries differ widely in chemistry construction, which makes it difficult to create efficient recycling systems. Scientists, meanwhile, say effective battery recycling will require more than just technological advances. The high cost of transporting used batteries over long distances can discourage recycling. It causes an economic barrier: It's often cheaper for battermakers to buy freshly-mined metals than to use recycled materials.

"The need for progress is becoming pressing," says Linda Gaines, who works on battery recycling. "The sooner we can get everything moving, the better." To jump-start recycling, governments and industry are putting money into research centers. Scientists are working to ensure the EV batteries being sold today can be recycled in 2030 and beyond, when thousands of batteries will reach the end of their lives. "There's little time to waste.” says Linda.

3 . Colombia's Chiribiquete National Park, which is the largest protected tropical forest in the world, was just named a UNESCO World Heritage Site for its outstanding global value for nature and people. It was built in 1989 and has been enlarged twice and now covers 4. 4 million hectares in the Northern Amazon. This is a great win for environmentalists

Chiribiquete National Park has a high rate of species variety. It is home to almost 3, 000 animal and plant species, many of which are endangered outside of this amazing protected area. The park is also home to a huge amount of species that are distinctive to this area. Some of them have been decided to be many years old. According to UNESCO, the park, which is located in the middle of two Pleistocene refuges and functions as a corridor(走廊) between three bio-geographic provinces, hosts many special species. "

The National Heritage designation(称号)marks the great success of decades of joint conservation(保护)efforts by the Colombian government, the World Wide Fund for Nature(WWF), and other environmental organizations. “This is an important moment for the protection of key ecosystems in Colombia, " said Mary Lou Higgins, Director of WWF Colombia. "The recognition of this unique place as a World Heritage Site is an important step toward protecting forests for future generations. It is a milestone for the Amazon and for forest conservation globally. "

Colombian president Juan Manuel Santos said that he welcomed the UNESCO designation and considered it as great news for Colombia. He promised to increase the conservation funds by an additional $525 million to better protect the country's environment. However, it is still a long way to go in protecting the park for generations to come.

7 . Japan is particularly vulnerable to natural disasters because of its climate and topography(地形), and it has experienced countless earthquakes, typhoons, and other types of disasters.

A number of factors contribute to the high incidence of natural disasters in Japan. Firstly, the country faces extreme climate changes, such as seasonal rain fronts and typhoons, as well as heavy snowfall on the Sea of Japan. Secondly, Japan's topography is rugged(崎岖不平的). Thirdly, Japan is located in the Pacific earthquake belt and is often struck by earthquakes, while its complex coastline is vulnerable to tsunamis. And fourthly, Japan is located in the circum-Pacific zone, in which almost all the volcanoes of the world are concentrated, and has 83 active volcanoes—one-tenth of the world total.

Between the end of World War Il and the late 1950s, when Japan's defenses against disasters were weakened by the war, the country was hit by a series of major typhoons, violent earthquakes, and other disasters, and over 1, 000 lives were lost almost every year. The Ise Bay Typhoon of September 1959 killed more than 5,000 people, the biggest number in the postwar period. It urged the establishment of a planned and complete disaster prevention administration system, and in 1961 the Disaster Countermeasures Basic Act was made. After that measures for prevention, emergency relief, and recovery were linked interactively under a system that ensured effective ways to disaster countermeasures. In June 1960 a decision was reached to observe a "Disaster Prevention Day" each year on September 1 as a means of spreading disaster prevention knowledge and raising public awareness.

Japan in the 1960s thus began actively carrying out measures to shore up both the physical and institutional safeguards against disasters, with particular measures being placed on disaster prevention. These efforts have greatly reduced the number of people who die or become missing as a result of natural disasters. The declining trend is still continuing, and the number has fallen to between 100 and 200 per year in recent years.

8 . Some of the oldest art in human history is being damaged, scientists say. And climate change may be speeding up its loss. New research reports that ancient rock art in Indonesian caves is degrading over time, as bits of rock slowly break off from the walls. It's a huge loss for human history.

Salt crystals（结晶）building up on the walls are a key part of the problem, the study suggests. These salt crystals go into the cave walls, changing sizes as temperatures rise and fall. This process causes the rock to slowly break down.

Salt crystals may become larger when exposed to repeated changes between wet conditions and periods of drought. These kinds of changes are expected to become more obvious as the climate continues to warm.

In particular, the researchers say, climate change may cause more intense El Nino （厄尔尼诺）events in the future. These events can strengthen the kinds of conditions that help salt crystals form Scientists are still debating the exact influence of climate change on El Nino, a natural climate cycle that drives changing patterns of warming and cooling in the Pacific Ocean.

The new study, led by Jillian Huntley, examined 11 ancient cave art sites in South Sulawesi, Indonesia. The researchers found evidence of salt formation at all 11 sites. It's merely a small part There are more than 300 known eave art sites around the region. The researchers note that salt crystals may indeed be part of the problem, adding that climate change is a growing threat, one that deserves more attention.

9 . An Ontario teen is making waves by turning old fishing gear into new treasures. Since last year, Natalie, 15, has been taking lost or thrown — away fishing nets and rope and transforming them into bracelets, rope art, mats, baskets and necklaces.

Last year, Natalie was working on an assignment for her science, technology, engineering and mathematics (STEM) class. As part of the assignment, she learned about “ghost nets”, which are fishing nets that have been left or lost in the ocean by people who fish.

“They have huge effects on our environment. They can kill coral reefs and many animals,” said Natalie. “46 percent of the Pacific garbage is ghost gear.” The Great Pacific Garbage is a huge collection of trash floating in the Pacific Ocean between Hawaii and California.

Natalie told her mom she wanted to do something to help. She got in touch with a handful of charities, including the Sea Protection Society and Coastal Action.

After getting some shipments of ghost nets and rope from those organizations, Natalie, with the help of her family, started turning the discarded gear into new artworks. “We've made bracelets, rope art, mats, baskets, and we've made necklaces, which also use beach glass in them,” she said. Natalie then started selling the artworks online, the crafty buying and selling website.

She donated all her profits-minus a small sum of change to cover supplies — to the charities that donated fishing supplies to her. She's also been donating all the income from her non-profit business, called Nautical Waters, to charity. Natalie said she hoped to continue her passion for ocean life, with plans to study marine biology in university.