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Some of the world’s most significant problems never hit headlines. One example comes from agriculture. Food riots and hunger mak
Some of the world’s most significant problems never hit headlines. One example comes from agriculture. Food riots and hunger mak
admin
2019-03-20
75
问题
Some of the world’s most significant problems never hit headlines. One example comes from agriculture. Food riots and hunger make news. But the trend lying behind these matters is rarely talked about. This is the decline in the growth in yields of some of the world’s major crops. A new study by the University of Minnesota and McGill University in Montreal looks at where, and how far, this decline is occurring.
The authors take a vast number of data points for the four most important crops: rice, wheat, corn and soyabeans(大豆). They find that on between 24% and 39% of all harvested areas, the improvement in yields that took place before the 1980s slowed down in the 1990s and 2000s.
There are two worrying features of the slowdown. One is that it has been particularly sharp in the world’s most populous(人口多的)countries, India and China. Their ability to feed themselves has been an important source of relative stability both within the countries and on world food markets. That self-sufficiency cannot be taken for granted if yields continue to slow down or reverse.
Second, yield growth has been lower in wheat and rice than in corn and soyabeans. This is problematic because wheat and rice are more important as foods, accounting for around half of all calories consumed. Com and soyabeans are more important as feed grains. The authors note that " we have preferentially focused our crop improvement efforts on feeding animals and cars rather than on crops that feed people and are the basis of food security in much of the world. "
The report qualifies the more optimistic findings of another new paper which suggests that the world will not have to dig up a lot more land for farming in order to feed 9 billion people in 2050, as the Food and Agriculture Organisation has argued.
Instead, it says, thanks to slowing population growth, land currently ploughed up for crops might be able to revert(回返)to forest or wilderness. This could happen. The trouble is that the forecast assumes continued improvements in yields, which may not actually happen.
How does the author view the argument of the Food and Agriculture Organisation?
选项
A、It is built on the findings of a new study.
B、It is based on a doubtful assumption.
C、It is backed by strong evidence.
D、It is open to further discussion.
答案
B
解析
观点态度题。原文第五段提到了联合国粮食农业组织的乐观预测,最后一段第一、二句首先说明这一预测是有可能发生的,而第三句才是作者真正的观点,即该预测的问题在于假设产量会持续增加,但是这未必会发生。故答案为B)“它是基于不可靠的假设”。
转载请注明原文地址:https://kaotiyun.com/show/hbZ7777K
0
大学英语四级
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