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
考研
Most people may drink only two liters of water a day, but they consume about 3 000 if the water that goes into their food is tak
Most people may drink only two liters of water a day, but they consume about 3 000 if the water that goes into their food is tak
admin
2017-11-14
29
问题
Most people may drink only two liters of water a day, but they consume about 3 000 if the water that goes into their food is taken into account. The rich gulp down far more, since they tend to eat more meat, which takes far more water to produce than grains. So as the world’s population grows and incomes rise, farmers will need a great deal more water to keep everyone fed; 2 000 more cubic kilometers a year by 2030, according to the International Water Management Institute (IWMI). Yet in many farming regions, water is scarce and likely to get scarcer as global warming worsens. The world is facing not so much a food crisis as a water crisis, argues Colin Chartres, IWMI’s director-general.
The solution, Mr. Chartres and others contend, is more efficient use of water or, as the sloganeers put it, "more crop per drop". Some 1.2 billion people live in places that are short of water. Farming accounts for roughly 70% of human water consumption. So when water starts to run out, farming tends to offer the best potential for thrift. But governments rarely charge farmers a market price for water. So they are usually more wasteful than other consumers—even though the value they create from the water is often less than households or industry would be willing to pay for it.
The pressing need is to make water go further. Antoine Frerot, the head of the water division of Veolia Environment, promotes recycling of city wastewater to be used in industry or agriculture. This costs less and cuts pollution.
Yet as Mr. Frerot himself concedes, there are many even cheaper ways to save water. As much as 70% of water used by farmers never gets to crops, perhaps lost through leaky irrigation channels or by draining into rivers or groundwater. Investment in drip irrigation, or simply repairing the worst leaks, could bring huge savings.
Fanners in poor countries can usually afford such things only if they are growing cash crops, says David Molden of IWMI. Even basic kit such as small rainwater tanks can be lacking. Ethiopia, for example, has only 38 cubic meters of storage capacity per inhabitant, compared to almost 5 000 in Australia. Yet modest water storage can hugely improve yields in rain-fed agriculture, by smoothing over short dry spells. Likewise, pumping water into natural aquifers for seasonal storage tends to be much cheaper than building a big dam, and prevents the great waste of water through evaporation.
Agronomists are beginning to devise tools to help monitor the efficiency of water use. Some have designed algorithms that use satellite data on surface temperatures to calculate the rate at which plants are absorbing and transpiring water. That allows governments and development agencies to concentrate their efforts on the most prodigal areas.
Raising yields does not always involve greater water consumption, especially when farms are inefficient. It would take little extra water to double cereal output in many parts of Africa, Mr. Molden argues. IWMI reckons that some three-quarters of the extra food the world needs could be provided simply by bringing yields in poor countries closer to those of rich ones. That is more realistic than the absolute alternative; giving up meat and other thirsty products altogether.
[A] cultivating cash crops
[B] leaking irrigation system
[C] expenses and efficiency
[D]surface temperature data
[E] low water price
[F] water shortage
[G] food crisis
The water use rate of plants is computed with
选项
答案
D
解析
题目对应信息在倒数第二段第二句:Some have designed algorithms that use satellite data on surface temperatures to calculate the rate at which plants are absorbing and evaporating water.大意是,一些农学家设计了一些算法,利用地表温度卫星数据来计算植物吸收和蒸发水分速度。题干中water use rate of plants“植物对水的利用速度”概括了原文the rate…evaporating water“植物吸收和蒸发水速度”的说法。
转载请注明原文地址:https://jikaoti.com/ti/n9k7FFFM
0
考研英语一
相关试题推荐
Inspiteof"endlesstalkofdifference",Americansocietyisanamazingmachineforhomogenizingpeople.Thereis"thedemocrat
Americansnolongerexpectpublicfigures,whetherinspeechorinwriting,tocommandtheEnglishlanguagewithskillandgift.
Teachersneedtobeawareoftheemotional,intellectual,andphysicalchangesthatyoungadultsexperience.Andtheyalsoneed
WhenPaulGorski,thefounderofanorganizationcalledEdChange,visitscollegesanduniversitiestoadvisethemoncampusdive
Socialsciencehasweighedinonthe"tigermom"debate,anditlookslikeeveryoneisright:Bothover-protectiveandlaid-back
Historiansareunderstandablyreluctantaboutpredictingthefuturebecauseofalltheunknownvariablesinvolved.Forexample,
Familiarasitmayseem,gravityremainsamysterytomodernphysics.Despiteseveraldecadesoftrying,scientistshavefailed
Islamiclawisaparticularlyinstructiveexampleof"sacredlaw".Islamiclawisaphenomenonsodifferentfromallotherforms
Thiseyeontheconsumerapproachisknownasthemarketingconcept,whichsimplymeansthatinsteadoftryingtosellwhatever
随机试题
高级语言的翻译过程有两种形式:______和______。
给定曲线y=x3与直线y=px—q(其中p>0),求p与q为何关系时,直线y=px—q是y=x3的切线.
下列哪种氨基酸必须由食物提供
患者,女,58岁。绝经数年,忽又来潮,量多、色淡,肌热面赤,烦渴欲饮,脉洪大而虚。治疗应选用()
A、变态反应B、特异质反应C、停药反应D、后遗效应E、快速耐受性青霉素引起的过敏性休克属于( )。
两个或两个以上合作单位之间,以承包人的名义,为共同承包工程建设项目而签订的合同,一般称为()。
在多台起重机共同抬吊一个重物时,重物的重量分担往往是不均衡的。在起重工程中,以不均衡载荷系数计入其影响,一般不均衡载荷系数Κ2取()。
如果仝球变暖导致海平面大幅上升,和其他国家一样,中国将要_________被海水淹没地区的人口,特别是长江下游河段,或者建造大坝保护地处低洼地区的沿海城市,这些都需要巨大的花费。中国和其他国家面临的挑战是限制二氧化碳的排放,从而_________全球变暖所
世界之最是指在全世界范围内最突出的某一人、事、物等。下列世界之最的说法错误的是()。
一台交换机的总带宽为8.8Gbps,如果该交换机拥有两个全双工1000Mbps光端口,那么最多还可以提供的全双工10/100Mbps电端口的数量是()。
最新回复
(
0
)