(中学篇)2015年第10期:例谈高中英语读写课教学中词汇处理的策略(浙江:岑璐)一文涉及的课外补充阅读材料

Is your Diet Destroying the Environment?
 
A vegetarian diet is often praised for its health benefits. Studies have shown that vegetarians usually have lower levels of heart disease and a lower risk of diabetes (糖尿病) than people who eat meat. What most people are less aware of, however, are the effects that a vegetarian diet can have on the environment.
 
Researchers from the Union of Concerned Scientists in the US recently studied how consumer behavior affects the environment. The study showed that meat consumption (消耗) is one of the main ways that humans can damage the environment, second only to the use of motor vehicle.
 
Then, how can eating meat have a negative effect on the environment? The most important impact of meat production is through the use of water and land. 2,500 gallons of water are needed to produce one pound of beef, whereas 20 gallons of water are needed to produce one pound of wheat. One acre of farmland used for raising livestock can produce 40,000 pounds of potatoes, 30,000 pounds of carrots, or 50,000 pounds of tomatoes. By producing crops instead of animals, we can make more efficient use of the land and water.
 
Furthermore, farm animals such as cows,pigs,and sheep release methane (沼气)gas by expelling gas from their bodies. One cow can produce up to 60 liters of methane each day. Methane gas is the second most common greenhouse gas after carbon dioxide. Many environmental experts now believe that it is more responsible for global warming than carbon dioxide. It is estimated that 25% of all methane released into the atmosphere comes from farm animals.
 
People are becoming aware of the benefits of switching to a vegetarian diet,not just for health reasons, but also because it plays a vital role in protecting the environment. Some people go further, and eat a vegan diet, which excludes all products from animal sources, such as cheese, eggs, and milk. However, some nutritionists believe it can be comparatively deficient in many necessary vitamins and minerals our bodies need.
 
Today, many people are concerned about improving their health, and about protecting the environment.switching to a vegetarian diet — or just eating less meat — is a good way to do both of these things at the same time.