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
18
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 sharp decrease of soil erosion in 1982 resulted from _____.
选项
A、the education of the USDA on farming technology
B、the practices of environmental protection on farming
C、the prevention of water runoff in the two large areas
D、the protection of plant residues around the whole year
答案
B
解析
细节推断题。根据1982定位到第四段,第二句话说了此项研究将这一成绩归功于美国农业部在二战后对土地保护所做的努力(conservation practice),因此B项的protection on farming正确。
转载请注明原文地址:https://jikaoti.com/ti/l1FRFFFM
0
考研英语一
相关试题推荐
Comparedwithothermodesoftransport,traintechnologymightseemtobeprogressingasslowlyasasuburbancommuterservicer
Comparedwithothermodesoftransport,traintechnologymightseemtobeprogressingasslowlyasasuburbancommuterservicer
Comparedwithothermodesoftransport,traintechnologymightseemtobeprogressingasslowlyasasuburbancommuterservicer
FortyyearsagoWalterMischel,anAmericanpsychologist,conductedafamousexperiment.Heleftaseriesoffour-year-oldsalon
Mike,oneofyourfriends,issoaddictedtomakingfriendsontheInternetthathehaslittlesocialinteractioninreality.Yo
Publicimagereferstohowacompanyisviewedbyitscustomers,suppliers,andstockholders,bythefinancialcommunity,bythe
You,LiMing,asthedirectorofadigitalmediacompany,aredecidingtowriteamemorandumtothetrainingmanager,DavidPrin
Scholasticthinkersheldawidevarietyofdoctrinesinbothphilosophyandtheology,thestudyofreligion.Whatgivesunityto
ResearchersledbyNewYorkUniversityneuroscientistJosephLeDouxrecentlyclaimedtobethefirstscientiststoeraseasingl
Boysandgirlsusedtogrowupandsetasidetheirchildishpursuits.Notanymore.Thesedays,menandwomenholdontotheirin
随机试题
藿香善治
经脉中可用离、合、出、入来概括其循行特点的是
下列说法正确的是()
下列属于银行业监督管理目标的是()。
实收资本的金额和企业注册资本的金额总是相等的。()
汉地佛教寺院造像组合中,“华严三圣”指的是()。
阅读下面的文字,按要求作文。古罗马哲人赛涅卡说,人的生命如同寓言,不在于长短,而在于内容,有内容的生命自然是精彩的。生物学家达尔文说,自然界中包括人类在内的各种生命的存在本身就是一种精彩。对此,你又是如何看的呢?请以“精彩的生命”为标题
大嘴鲈鱼只在有鲦鱼出现的河中长有浮藻的水域里生活。漠亚河中没有大嘴鲈鱼。从上述断定能得出以下哪项结论?I.鲦鱼只在长有浮藻的河中才能发现。Ⅱ.漠亚河中既没有浮藻,又发现不了鲦鱼。Ⅲ.如果在漠亚河中发现了鲦鱼,则其中肯
藏族有一句民谚:“天平是轻重的衡量器,实践是是非的试金石。”美国也有一句谚语:“只有实践的钥匙,才能打开真理的宝库。"它们同样地反映了这样一个哲学观点()
以……为中心
最新回复
(
0
)