首页
登录
职称英语
Given that 8 percent of food crops grows faster on farms using grou
Given that 8 percent of food crops grows faster on farms using grou
游客
2025-02-22
9
管理
问题
Given that 8 percent of food crops grows faster on farms using groundwater
than the aquifers are replenished, and many large rivers are so heavily diverted
that they do not reach the sea for much of the year, researchers believe
Line freshwater sources-underground aquifers and rivers-are stressed. Better
(5) management of soil and water and creative cropping patterns can boost
production from rainfall-watered cropland, but the heaviest burden will fall on
irrigated land. At present, most farmers irrigate their crops by channeling
water down their fields in parallel furrows.
One alternative, drip systems, enables farmers to deliver water directly to
(10) the plants’ roots drop by drop, nearly eliminating waste by distributing water at
low pressure through a network of perforated plastic tubing installed on or
below the surface of the soil, where it then emerges through small holes at a
slow but steady pace. Because the plants enjoy an ideal moisture environment,
drip irrigation usually offers the added bonus of higher crop yields. Another
(15) alternative, sprinklers, can perform almost as well as drip methods when
designed properly, but traditional high-pressure irrigation sprinklers spray
water high into the air to cover as large a land area as possible, and the more
time the water spends in the air, the more of it evaporates before use.
Despite the payoffs, the higher costs of these technologies relative to
(20) simple flooding methods have been a barrier to their spread, and so has the
prevalence of national water policies that discourage rather than foster efficient
water use. Many governments have set very low prices for publicly supplied
irrigation, leaving farmers with little motivation to invest in ways to conserve
water or to improve efficiency and most authorities have also failed to regulate
(25) groundwater pumping, even in regions where aquifers are over-tapped.
Therefore, farmers might be inclined to conserve their own water supplies if
they could profit from selling the surplus, but this practice is often discouraged.
Efforts aside from irrigation technologies are also conducive to the
reduction of agricultural demand for water; for instance, measurements of
(30) climate factors such as temperature and precipitation can be fed into a computer
that calculates how much water a typical plant is consuming, and farmers can
use this figure to determine, quite accurately, when and how much to irrigate
their particular crops throughout the growing season. But the most effective, if
unlikely way, to do more with less water is to reconfigure our diets, especially
(35) the typical North American diet, which, with its large share of animal products,
requires twice as much water as diets common in many Asian and some
European countries. Eating lower on the food chain could allow the same
volume of water to feed two Americans instead of one, and despite the resultant
loss of nutrition, this may be the only recourse for countries serious about
(40) reducing their aquifer strain. [br] Most nearly parallel, in its fundamental approach to the drip system solution described in the passage would be a machine designed to
选项
A、save electricity by converting unused sunlight into power through the use of photocells
B、waste less electricity by insulating and reducing resistance in the conduits of the power grid
C、increase electrical efficiency by requiring consumers to use appliances that rely on less electricity
D、create a more reliable power grid by supplying electricity from a wider range of power plants
E、reduce the electricity necessary to powering a city by encouraging denser population growth
答案
B
解析
转载请注明原文地址:https://tihaiku.com/zcyy/3967805.html
相关试题推荐
Giventhat8percentoffoodcropsgrowsfasteronfarmsusinggrou
Giventhat8percentoffoodcropsgrowsfasteronfarmsusinggrou
Giventhat8percentoffoodcropsgrowsfasteronfarmsusinggrou
RichardM.Russellsaid52percentofthenation’sgrowthsincetheSecondWorld
BecausetheymakeupjustasmallpercentofallobjectsthatfalltoEarth,car
ThattheThirdBattalion’sfifty-percentcasualtyratetransformeditsassaulto
WhenEarthformed4.6billionyearsago,theSunburnedonly70percentasb
Thetablebelowgivesinformationaboutthepercentageoflandcoveredbyfo
Thegraphshowsthepercentageofmenandwomenemployedinexecutivepositi
Thelinegraphshowsthepercentageofpeoplewhohavecriminalrecordsatd
随机试题
[originaltext]M:Mrs.Hudson,anewresearchshowsthatevenjustfiveminutes
[originaltext]W:Mr.Brown,I’dliketotalktoyouaboutsomethingthatisget
会计计量单位只有一种,即货币计量。()
泪液中的粘蛋白成分来源于A.角膜上皮细胞 B.结膜上皮细胞 C.结膜杯状细胞
田汉是话剧方面实践和创造的先驱,也是改良旧剧的倡导者和实践者,是中国话剧运动名副
土样制备方法不同,所得击实试验成果不同,以下哪个结论是正确的:()A.最大干密
关于应激时血液系统的变化,错误的是A.慢性应激时红细胞数量增加 B.急性应激时
以下服用舌下片的注意事项中,错误的是A.给药宜迅速、把药片放于舌下 B.含服时
信用政策决定了企业应收账款赊销效果的好坏,信用政策主要包括()A、信用期间
关于乙型肝炎病毒特征叙述错误的是A、电镜下可见3种颗粒形态 B、完整病毒称为D
最新回复
(
0
)