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
One of the least appreciated but most remarkable developments of the past 60 years is the extraordinary growth of American agric
One of the least appreciated but most remarkable developments of the past 60 years is the extraordinary growth of American agric
admin
2015-07-13
42
问题
One of the least appreciated but most remarkable developments of the past 60 years is the extraordinary growth of American agriculture. Farming now accounts for about one tenth of the gross domestic product yet employs less than 1 percent of all workers. It has accomplished this feat through exceptionally high growth in productivity, which has kept prices of food low and therebycontributed to rising standards of living. Furthermore, the exportable surplus has kept the trade deficit from reaching unsupportable levels. Agriculture not only has one of the highest rates of productivity growth of all industries, but this growth appears to have accelerated during the past two decades.
Over the period 1948 to 2004, total farm production went up by 166 percent. The land used for farming dropped by one quarter over the 56-year period, and investment in heavy farm equipment and other capital expenditures decreased by 12 percent. Several developments drove these changes, beginning with the replacement of the remaining horses by tractors immediately after World War II and with the expanding use of fertilizers and pesticides. Later came the adoption of hybrid seeds, genetic engineering of plants and improved livestock breeding.A key element was the U.S. Department of Agriculture’s (USDA) extension service. Operating through land-grant universities and other organizations, it educated farmers on biotechnology, pest management and conservation.
For many years, critics have claimed that modern agriculture is not sustainable, one of the major assertions being that it encourages erosion, which will eventually wash away most of the topsoil Lost topsoil, the argument goes, is virtually irreplaceable because it takes up to 300 years for one inch of soil to form.
But a detailed study of two large areas, the Southern Piedmont and the Northern Mississippi Valley Loess Hills, showed that based on 1982 data, soil loss has dropped sharply from the very high rates of the 1930s. The study attributed the decrease in soil erosion to the USDA, which urged farmers after World War Ⅱ to adopt conservation practices such as strip cropping, whereby alternating rows are planted, and leaving plant residues in the fields year-round to inhibit water runoff.
Despite being a robust contributor to the U.S. economy, modem agriculture is not without a dark side. Runoff of fertilizers, antibiotics and hormones degrade the environment and can upset the local ecology. If not grown properly, genetically modified crops could spread their DNA to conventional species.
The "dark side" (Para. 5) implies that modern agriculture will _____.
选项
A、have a great impact on the U.S. economy development
B、lead to ecology pollution, if improperly controlled
C、have to decrease the soil erosion
D、change the DNA of conventional species
答案
B
解析
观点态度题。根据最后一段的内容可知现代农业也有负面影响,即题干中的dark side,根据文中的degrade the environment及upset the local ecology可知,B项符合文意。
转载请注明原文地址:https://kaotiyun.com/show/8M74777K
0
考研英语一
相关试题推荐
Asksomeonetonameafamouspsychologist,andchancesaretheywillpickSigmundFreud,thebeardedAustrianacademicwhocame
FortyyearsagoWalterMischel,anAmericanpsychologist,conductedafamousexperiment.Heleftaseriesoffour-year-oldsalon
Wehaveknownforalongtimethattheorganizationofanyparticularsocietyisinfluencedbythedefinitionofthesexesandt
ManyforeignerswhohavenotvisitedBritaincallalltheinhabitantsEnglish,fortheyareusedtothinkingoftheBritishIsle
Youhavelosttheoriginalofadiplomayoureceivedfromacollegewhereyoustudied.Writetothedirectorofthecollegetoa
Youhadabirthdaypartyatyourhomerecently,butyouunintentionallyneglectedtoinviteaclosefriendofyours—Meilin.W
Nowmedicalresearchersarediscoveringatruism:"alcoholandtobaccodonotmix."Thesetwosubstances,bothdangeroustoheal
Scholasticthinkersheldawidevarietyofdoctrinesinbothphilosophyandtheology,thestudyofreligion.Whatgivesunityto
In1926,whilefilmingTheKingofKings,directorCecilB.DeMillemovedhiscastandcrewtoCatalinaIsland,offthecoastof
Boysandgirlsusedtogrowupandsetasidetheirchildishpursuits.Notanymore.Thesedays,menandwomenholdontotheirin
随机试题
决定资本主义社会中劳动力价值的因素中对各因素都有影响和渗透作用的因素是()
风寒表证兼有湿邪者,可选用下列哪种祛风湿药
A.清热生津,益气和胃B.清热泻火,生津除烦C.清热解毒,疏风散邪D.泻火解毒,清上泄下E.泻火养阴,退热除蒸
患者,男,40岁。间断颜面及下肢水肿2年,晨起时明显,双下肢轻度水肿,尿少,乏力,无恶心、呕吐、黄疸,既往体健。BP:150/90mini-Ig,24小时尿蛋白定量:887.6mg。血常规:Hb101g/L。尿常规:尿蛋白(++),RBC10~24/H
患者,男性,74岁,患高血压20余年。突然剧烈头痛伴呕吐,继而昏迷,出现脑疝症状。在通知医生的同时,首先要做好的准备是
渗流流速v与水力坡度J的关系是:
关于木材的强度,下列说法错误的是()。
作为科委副主任,你要做一个怎样的课题研究招标。来为北京的社会公共安全提供支持?
和平共处
【S1】【S10】
最新回复
(
0
)