【推荐1】Spring soccer season is under way, and many youth leagues are playing under new safety rules. In November, the US Soccer Federation said that players on its teams who are 10 or younger are no longer allowed to head the ball Players ages 11 to 13 have limits on how often they can practice heading. The new rules are made to prevent kids from getting concussions (脑震荡)—injuries caused by a blow to the head that shakes the brain. Common problems include headaches and dizziness. Severe concussions can lead to long brain damage.

Heading the ball can be one of the riskiest parts of soccer. Sometimes the force of hitting the ball with their heads gives players concussions. But more often, players receive concussions when they accidentally knock heads with other players and hit their heads on the grass. “More concussions happen during the act of heading than any other action in soccer,” explains Dr. Robert Cantu, an expert on brain injuries.

So far, the new rules are made only to teams that are part of the US Soccer Federation. But the group says it hopes other leagues will soon follow its example.

Former US soccer star Brandi Chastain is one of the leaders of the activity to ban heading in youth soccer. She applauds the rule change. Last month, Chastain showed her determination of learning more about the effects of heading when she promised to donate her brain to science after she dies.

“If there’s any information to be gathered on the study of someone like me，who has played soccer for 40 years, it feels like my responsibility,” Chastain told The New York Times.

【推荐2】Las Vegas city in Nevada is built in a desert. The city may be known to the world for its partying. But officials have found that there are 21 square kilometers of useless grass. The grass is never laid on, played on or even stepped on. The grass is only there to look nice.

Now, the city is asking the Nevada state legislature (立法机构) to ban useless grass. It is trying to become the first place in America to ban that kind of grass often seen between streets, in housing developments and in office parks.

Useless grass nearly makes up 40% of all the grass in Las Vegas and it needs lots of water to survive. Grass needs four times more water than dry climate plants. By tearing out the grass, the city could reduce yearly water usage by 15%.

In 2003, the Southern Nevada Water Authority banned developers from planting grass in front of new homes. It also offered homeowners $30 for each square meter of grass they tear out. But fewer people are now using the program. Water usage has increased here by 9% since 2019. And last year, Las Vegas set a record of 240 days without major rainfall. The Colorado River provides much of Nevada’s drinking water. The river could lose more water as climate change affects it.

Water officials in other dry cities said water usage needs to be reduced. But they fear the reaction to reforms like the ones in Las Vegas if their communities do not accept them. Cynthia Campbell is the water resources adviser for the city of Phoenix in Arizona. “The city restrictions (限制) may get too hard for some residents (居民). They’ll say that is the point of no return for them,” Campbell said. “For some people, it’s a pool. For some people, it’s grass.”

【推荐3】Many cities and towns have laws that require people to recycle paper and plastics. Now some state and local governments have passed laws that require citizens to recycle their food waste as well. California and Vermont have statewide laws about recycling food waste that apply to businesses and homes. The process of recycling food waste and turning it into usable soil is called composting (堆制肥料).

Food waste that can be composted includes fruit and vegetable peels, coffee grounds, tea bags, and eggshells. Garden waste such as stems and leaves can also be composted. Meat, fish, and dairy food waste cannot be recycled.

According to environmental groups, composting reduces the amount of trash going into landfills, and composted waste holds a wide range of nutrients (营养物). When compost is added to the soil in gardens and fields, it helps crops grow. 

Reducing the amount of waste that goes into landfills is one reason why cities and states are passing food-waste recycling laws. “Our landfills are far from enough for the creation of new ones is shrinking.” Renee Crowley, a project manager at the Lower East Side Ecology Center in New York City, told TFK.

Officials in Seattle, Washington, say that food waste makes up 30% of the trash going into landfills, and they are looking to reduce that percentage. That city has a law requiring people to recycle food waste. It is banned from all garbage. There is a fine (罚款) for people who put it into regular garbage.

Those who are against food-recycling laws say that the composting process is costly. In addition, it can be difficult for people who live in apartments to store their waste because they don’t have access to outside storage bins. Patti Ferguson from Orange County, California, told her local newspaper that she thought an indoor container containing food waste would get smelly.

【推荐1】Anyone watching the Winter Olympics in Beijing, China over the last few days has seen lots and lots of snow-man-made snow. Since the area gets little natural snow, this is the first time the Winter Olympics is taking place on almost 100% artificial snow.

This year’s Winter Olympics is being held in Beijing, China, and in two areas northwest of Beijing, Yanqing and Zhangjiakou. The areas get cold in the winter, but they don’t get a lot of snow. That’s because they’re not far from the Gobi Desert, and are generally very dry.

That meant some serious changes were needed to hold the Winter Olympics there. China took water from a reservoir which helps supply Beijing’s drinking water and sent it to a nearby river. To carry the water to the mountains for making snow, the country ran miles and miles of pipes. China says making the snow took about 49,000 gallons of water. Outside experts say it probably took a lot more water than that.

China hired an Italian company called TechnoAlpin to create the snow. TechnoAlpin created artificial snow at several earlier Winter Olympics. For the snow in this year’s Olympics, TechnoAlpin laid over 40 miles (64 kilometers) of pipe and brought in hundreds of snow-making machines. Even with all of those machines, making the snow for this year’s Games took seven weeks.

In recent years, it has become more and more common to use artificial snow at winter sports events. That’s true even in places that used to have a lot of snow naturally. Some artificial snow was used in the Winter Olympics in 2010 and 2014 because of warm weather. In the 2018 Games in Pyeongchang, South Korea, roughly 90% of the snow was man-made. As the world warms because of climate change, problems like this are expected to become far more common. Michael Mayr, who leads TechnoAlpin in Asia, says, “You could not have winter sports now without man-made snow.”