Organicfarmingavoidstheuseofchemicalpesticidesandman-ma...
問題詳情:
Organic farming avoids the use of chemical pesticides and man-made fertilizers. Supporters say organic farming is better for the environment than traditional methods. But studies have shown that organic farming generally produces less food per hectare.
That lower yield means feeding the world organically would require more land. But good farmland is limited. And scientists say deforestation (砍伐森林)from the clearing of land for agriculture is already a problem for climate change.
In a new study, researchers wanted to measure the difference between traditional and organic yields. So they combined the results of sixty-six earlier studies. They found that some organic farms can produce almost as much as traditional farms. But most cannot.
Traditional yields are typically higher than organic yields. But with certain management practices, certain environmental conditions, and certain crop species, this yield difference can be quite small. On average, organic farms produced twenty-five percent less compared to traditional farm. But yields of organic fruits and other perennial (多年生長的) crops nearly equaled the yields from traditional ones.
However,organic vegetables and cereal crops (穀類作物)like maize (玉米)and wheat had a lot lower yields compared to traditionally grown crops.
The soil on organic farms holds water better, and that can reduce the yield difference. Also, organic fanners can improve their yields by making sure their crops get enough fertilizer.
The United Nations predicts that world demand for food will grow seventy percent by the middle of the century. John Reganold is a soil scientist at Washington State University. He says no one should remove organic agriculture as part of the solution.
nold—who was not part of the study—says farming is increasingly a combination of organic and traditional methods.
8. What can reduce the yield difference between organic and traditional farming?
a. certain farmlands
b. certain crop species
c. certain environmental conditions
d. certain management practices
A. a, b, c B. a, c, d C. b, c, d D. a, b, d
9. What does the underlined word “yield” in Paragraph 2 most probably mean?
A. Nutrition. B. Output. C. Profit. D. Production.
10. What’s John Reganold’s attitude towards avoiding the use of organic farming?
A. Negative. B. Positive. C. Supportive. D. Uncertain.
11. The passage is most probably .
A. a news report B. an agriculture report
C. a science report D. an educational report
【回答】
CBAB
知識點:科普環保類閱讀
題型:閱讀理解
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