Bees may soon need to add protein shakes to their diet. Pollen(花粉) normally provides their protein(蛋白质). But rising levels of carbon dioxide (CO₂) in the air have reduced the protein in pollen. That's what a new study finds.

    Scientists compared recently collected flowers from Canada goldenrod. Then they compared pollen in them to pollen in goldenrod reserved at a museum in Washington, DC. They found today's plants have less protein. Protein levels in pollen from the older flowers were 18 percent. Today's goldenrod pollen has only about 12 percent protein. That's about one-third less than 172 years ago. Over that same period, CO₂ levels have gone up by more than one-third. Back more than 170 years ago, they were about 280 parts per million in air. Today they are about 398 ppm.

    To test whether CO₂ changes had played a role in the falling protein levels, the researchers did some tests. They grew goldenrod for two years at CO₂ levels of up to 500 ppm. More CO₂ in the air led to lower levels of protein in the flowers' pollen.

    Joan Edwards, one of the researchers, says that this drop in pollen protein could affect a bee's diet and health. It would be like eating junk food, tasting good but offering less nutrition(营养).

    Honeybees need to eat lots of protein. They use it to feed their young. They also need it to keep their immune systems healthy, says Cédric Alaux, a bee biologist at the French agricultural research agency.

    Bee populations have been decreasing worldwide in recent years. A drop in their food quality might play a role, Edwards says. And that drop might affect crops too. "The health of the bee population is not just for the flowers and the bees and biodiversity." She worries it also could play a role in "human health and well-being."

    Some years back, nobody paid much attention to the waste in homes and landfills. It became so vast that the government started getting concerned the phenomenon could create a disaster. A solution had to be found, but one that is kind to humans and the environment. . Below are the reasons why we need to recycle.

    Conserve natural resources

    . If a lot of pressure is put on these natural resources, they might be run out of fast. The only way to stop the pressure applied to these resources is recycling. According to the United States Environmental Protection Agency, recycling one ton of paper saves up about 17 trees as well as 7 tons of water.

Reduce carbon emissions

    Recycling greatly minimizes carbon emissions, commonly referred to as greenhouse gases. , they would end up being burned, giving out dangerous greenhouse gases. Whatever your opinion on global warming, a lot of people agree to the idea that everyone needs to play a role in minimizing the effects of pollution and emissions.

    Recycling has been proved to save up lots of energy. Companies that use recycled aluminum save up to 95% energy during production of aluminum products when compared to companies that source raw materials.

    One person can make a big difference

    Most people have already made up their minds that one person cannot make any difference in regard to recycling waste. That thinking might apply in other fields. In recycling, an individual can make a big difference. Averagely, every American produces about 1, 600 pounds of waste every year. Up to 1, 100 pounds of waste is able to be recycled every year per person. .

A. Save energy

B. Protect the environment

C. That's how recycling was born

D. If these wastes were not recycled

E. That represents half a ton per individual

F. Many kinds of resources are considered limited

G. You and your neighbor's effort to recycle will mean clean surrounding air