首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
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
29
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.
What does the new study by the two universities say about recent crop improvement efforts?
选项
A、They fail to produce the same remarkable results as before the 1980s.
B、They contribute a lot to the improvement of human food production.
C、They play a major role in guaranteeing the food security of the world.
D、They focus more on the increase of animal feed than human food grains.
答案
D
解析
推理判断题。由第四段第四句可知,研究者们认为人们偏向专注于提高喂养动物和为汽车提供能源的农作物的产量,而不是能养活人类的农作物的产量,故答案为D)“他们更加关注动物饲料而不是人类粮食产量的增加”。
转载请注明原文地址:https://kaotiyun.com/show/LbZ7777K
0
大学英语四级
相关试题推荐
TVLinkedtoLowerMarksA)Theeffectoftelevisiononchildrenhasbeendebatedeversincethefirstsetswereturnedon.Nowt
A、Youshouldthinkaboutthefuturewhenyoumove.B、Movingbringsopportunitiesaswellassomeproblems.C、Husbandandwifedo
A、Itsuitshim.B、Itlooksridiculous.C、Itlooksold.D、It’sgettingworse.A信息明示题。女士最后说秃顶并不可怕,有时还可以很吸引人,而自己的丈夫就秃顶,但她认为秃顶很适合她丈
中国的春节在农历(lunarcalendar)一月一日,是新一年的开始。这是举家团圆的时刻。一般说来,在春节前几天,只要有可能的话,多数人无论身处何地都会回家。就像圣诞节一样,人们会买很多东西如食品、礼物、衣服和烟花爆竹给孩子们。在除夕之夜,多数农村家庭
Themedicalworldisgraduallyrealizingthatthequalityoftheenvironmentinhospitalsmayplayasignificantroleinthepro
《本草纲目》(TheCompendiumofMateriaMedica)是明代(theMingDynasty)著名的医学家李时珍所著。这部著作近乎200万字,记载药物(medicalsubstance)1892种。除了中草药(Chinese
在中国,玉(jade)的历史可以追溯到商朝(theShangDynasty).数千年来,人们都视玉为最珍贵的石头。在古代,玉是仅限于宗教仪式的物品。在封建社会(imperialsociety),玉是财富和社会地位的象征。人们普遍相信玉能辟邪,能保护佩
传统中医(traditionalChinesemedicine)可以不借助任何仪器给病人治病,堪称奇迹。“望”、“闻”、“问”、“切”(pulsetaking)为传统中医诊断的四个方法。“望”指通过直接观察病人体表来了解情况。“闻”就是听声音、闻气味
科举制(imperialexaminationsystem)是中国古代朝廷(imperialgovernment)选拔官员的制度。它始于隋朝(theSuiDynasty),历时1300多年直到清朝(theQingDynasty)。科举考试在中
There’sNoPlaceLikeHome[A]Onalmostanynightoftheweek,Churchill’sRestaurantishopping.The10-year-oldhotspotinR
随机试题
活塞式压缩机其排气压力的高低取决于()。
小建中汤治疗虚劳的主要功用是()
Thereisclearevidence______themostdifficultfeelingofalltointerpretisbodilypain.
肾性高血压患者可选用
[2012专业案例真题下午卷]某新建2×300MW燃煤发电厂,高压厂用电系统标称电压为6kV,其中性点为高电阻接地。每台机组设两台高压厂用无励磁调压双卷变压器,容量为35MVA,阻抗值为10.5%,6.3kV单母线接线,设A段、B段。6kV系统电缆选为ZR
爱岗敬业是会计职业道德的精髓。()
给定资料 1.2013年11月12日,十八届三中全会闭幕。为期4天的全会听取并讨论了习近平受中央政治局委托作的工作报告,审议通过《中共中央关于全面深化改革若干重大问题的决定》。 全会提出,城乡二元结构是制约城乡发展一体化的主要障碍。必须健全体制机制
TheoreticalphysicistsusemathematicstodescribecertainaspectsofNature.SirIsaacNewtonwasthefirsttheoreticalphysici
下列对CSS内容表述不正确的一项是()。
Aboutacenturyagomorepeoplewouldnothaveappreciatedthestudyofaforeignlanguageastheydotoday.Gonearethosedays
最新回复
(
0
)