1 . In the U. S., people eat more protein than they need to, which might not be bad for human health, but does pose a problem for the country’s waterways. The nation’s wastewater is loaded with the leftovers from protein digestion: nitrogen compounds(氯化合物) that can feed harmful algal blooms(藻华) and pollute the air and drinking water.

Maya Almaraz, a biogeochemist at the University of California, Davis, and her team wanted to see how much of this nitrogen entered into the U. S. wastewater system because of a protein-heavy diet. The researchers found that the majority of nitrogen pollution present in wastewater—some 67 to 100 precent—is a by-product of water people consume.

Once it enters the environment, the nitrogen can have a series of ecological impacts. It helps algae grow much faster than they would normally, which is harmful to humans, other animals and plants. And when the algae eventually die, the problem is not over. Microorganisms(微生物) that feed on dead algae use up the oxygen in the water, leading to “dead zones,” where many species simply cannot survive, in rivers, lakes and oceans.

Although it is possible to treat algal blooms, many of the current methods are not always effective at getting rid of all of the harmful growth. Some of these methods can even lead to additional pollution. So the best strategy for dealing with the effects of nitrogen pollution is prevention, says Patricia Glibert, an ocean scientist at the University of Maryland. Almaraz and her team suggest that controlling nitrogen pollution could be approached more quickly with a change in eating habits that could save billions of dollars in the long term.

2 . A new study has found that light pollution is making the night sky brighter and the stars dimmer (暗淡的). The study examined data from more than 50, 000 citizen star watchers across the world, It found that man-made, or artificial lighting is making the night sky about 10 percent brighter each year. Data for the study was collected from 2011 to 2022.

The result was a much faster rate of change than scientists had estimated in the past. As cities expand and put up more lights, a “skyglow” is created in the sky. Skyglow is a term scientists use to describe light that becomes more intense. The research team gave an example to explain the result. If a child is born where 250 stars can be seen on a clear night, by the time that child turns 18, only 100 stars will be seen.

Past studies involving artificial lighting used satellite images of the Earth at night. They had estimated the yearly increase in sky brightness to be about 2 percent a year. But the satellites used are not able to identify light with wavelengths toward the blue end of the spectrum (光谱) — including light given off by energy-effective LED bulbs. The researchers noted that more than half the new outdoor lights put in across the United States during the past 10 years have been LED lights. The satellites are also better at finding light that gets spread upward like a spotlight than light that spreads out from side to side, Kyba said.

“Migratory songbirds normally use starlight to orient (确定方向) where they are in the sky at night,” said Georgetown University biologist Emily Williams. She was not part of the study. And when sea turtle babies hatch, they use light to orient toward the ocean — light pollution is a huge deal for them.

Falchi, the physicist at the University of Santiago de Compostela, said part of what is being lost is a universal human experience. “The night sky caused the generations before ours to have exciting new ideas or made them want to create something, especially in art, music, science and literature,” he added.

Japan said on Tuesday that it had decided to    1    (gradual) release tons of treated wastewater from the ruined Fukushima Daiichi nuclear plant (福岛第一核电站) into the ocean,    2     (describe) it as the best solution to dealing with the leftovers (残留物) from the Fukushima nuclear accident, one of the    3    (serious) in the world.

The    4    (decide) ends years of debate over how to deal with the water,    5    is enough to fill more than 500 Olympic-sized swimming pools.

“The Japanese government ignores concerns and strong opposition both at home and abroad. Such an    6    (responsilble)act not only directly harms the interests of the people in Japan’s neighbouring countries, but    7    threatens the global marine environment and international public health security,” Chinese Foreign Ministry spokesman Wang Wenbin said.

Greenpeace(绿色和平组织)criticized Japan’s plan and said there are other solutions that should    8    (censider). “    9    than using the best available technology to store and process the water    10    the long term, they have chosen the cheapest solution, damping the water into the Pactfie Ocean.”

Beaches across the planet share many features: sand, water, ocean gentle winds — and plastic. At Floyd Bennett Field, the coastal area     1     artist Barry Rosenthal goes collecting, rubbish piles up fast and in layers, as if at an archaeological (考古的) site.

Plastics will indeed be the product of our age,     2     (particular) in oceans where the material goes into ecosystems and floats around the world. More than millions and millions of pieces of plastic already fill the seas, with some nine million tons     3    (add) each year.

Rosenthal observed how bottles,     4    (toy), and food boxes fade, wear out, yet never disappear. He started building and photographing sculptures (雕像) of ocean trash to illustrate the problem of ocean pollution. Finally he began to gather the rubbish to use as his art materials, cleaning     5     small part of the coast over and over again. “I started to just collect as much as I could and go back to my studio to sort       6     out,” he says. Each sculpture has a theme, by color, shape, or intended use, such as the oil containers.

A project begun for aesthetics (美学) has got a     7    (two) purpose: raising social and environmental awareness. Over the last few years, Rosenthal     8    (tour) to speak about ocean pollution and what might help clean it up. The most     9    (meaning) advance, he says, would be to rethink our method of consuming (消费). “We need a change in all packaging design     10    (make) people feel good,” he says.

6 . Pollution is one of the biggest problems in the world today. In many places, rubbish is thrown into lakes and rivers.     1    

In some cities, the air is filled with pollution.     2     If it is not cleaned up, more people will be hurt.     3     Land and water pollution kills many animals every year.

If we do not act to improve the environment, more living things will be killed by pollution.

    4     We should separate rubbish into different groups. In this way, it can be recycled and reused. We had better plant more trees.     5     What’s more, we shouldn’t put the waste into lakes or rivers.

If we can do these, we will make the world a better place to live in.

7 . During a waste collection session in May at the base of Mount Qomolangma, in the Tibet Autonomous Region, participants put garbage（mostly plastics）into bags and prepared to transport them downhill.

Dressed in camouflage and a blue vest, Samdrub dragged a sack to a blue truck parked a few hundred meters away. Scores of similar sacks were piled up along the roadside, waiting to be loaded onto the vehicle. Not far away, a couple of sheep roamed the deserted land looking for grass. “Loads of it here. Loads of it. This is the fifth consecutive time we have come here and we still haven’t finished the clean-up, ” said Samdrub, 64, who, like many Tibetans only uses one name. Samdrub and her companions are members of a regular clean-up campaign organized by the Lhasa Ban-White Association, an environmental advocacy group that taps the volunteer spirit to control abandoned plastic trash, also known as “white pollution”. The volunteers are of all ages and come from different walks of life. Now retired and with time to kill, Samdrub and her friends have taken to the city’s ravines and riverbanks to battle the pollution. “In recent years, I’ve read reports that livestock choked and died after eating plastic. I was born and raised in rural Shigatse, and I know how big a financial loss that is for herders. ” Samdrub said.

Tersing Dorji, 62, a member of the Lhasa Ban-White Association, said the worst pollution results from rural farmers’ markets and the common use of plastic bags, which are super-thin and relatively expensive to recycle. “They are of various colors and very light, and when the wind blows they fly everywhere. ” she said.

A rule was then implemented by authorities in Lhasa that banned the production of super-thin plastics and ordered retailers to charge customers a fee if they wanted a regular plastic bag. The ban was later extended to the entire region. It has worked well generally, especially in supermarkets and other large operations, where additional charges for plastic bags have prompted many shoppers to opt for reusable items, such as cloth bags.