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
2017-07-09
20
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.
Farmers 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://kaotiyun.com/show/ojbZ777K
0
考研英语一
相关试题推荐
Thiseyeontheconsumerapproachisknownasthemarketingconcept,whichsimplymeansthatinsteadoftryingtosellwhatever
Finally,otherpeoplemaygiveusinstrumentalsupport—financialaid,materialresources,andneededservices—thatreducesstres
Peoplewereafraidtoleavetheirhouses,foralthoughthepolicehadbeenorderedtostandbyincaseofemergency,theywerej
【F1】Mostpeopleknowthatawkwardfeelingwhenyoushuffleintoanelevatorwithotherpeopleandtrynottomakeeyecontact.【
【F1】Mostpeopleknowthatawkwardfeelingwhenyoushuffleintoanelevatorwithotherpeopleandtrynottomakeeyecontact.【
Manyphilosophershavearguedthatpeoplemakedecisionsaboutwhat’srightandwrongbasedonmoralprinciplesandrationaltho
Manyphilosophershavearguedthatpeoplemakedecisionsaboutwhat’srightandwrongbasedonmoralprinciplesandrationaltho
Peoplewhoaredepressedareliterallysiekatheart:theyhaveasignificantlyincreasedriskforcardiovasculardisease,andn
Peoplewhoaredepressedareliterallysiekatheart:theyhaveasignificantlyincreasedriskforcardiovasculardisease,andn
随机试题
下列对IgA肾病诊断最可靠的依据是
胰腺内分泌部含有多种内分泌细胞,所以可以分泌多种消化酶。()
缺铁性贫血应用铁剂停药原则为
下列属于挡水建筑物的有()。
大华公司会计部门2012年开出和收到的票据情况如下:(1)2月5日,收到A公司开出的3个月期限的商业承兑汇票一张,注明的出票日期为2012年2月4日,金额10万元。(2)2月10日,大华公司向客户B企业开出一张支票,由于B企业的名称全称
下列各项中,与丧失现金折扣的机会成本呈反向变化的是()。
操作者自身的感觉系统提供的感觉反馈是______。
制发公文的目的和要求一般取决于()。
绿茶的主要成为是茶多酚。近来大量动物实验发现,茶多酚具有抑制肿瘤细胞增殖、促进肿瘤细胞消亡的作用。但是,有些专家通过对大量人群的研究,并未发现饮茶越多癌症发病率就越低这一现象。据此,他们并不认为经常饮茶能够防癌。以下哪项如果为真。则是上述专家作出结论最合理
在数据库的三级模式中,可以有任意多个
最新回复
(
0
)