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
2015-10-20
28
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 thereby contributed 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"(Line 1, Paragraph 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/JVzZ777K
0
考研英语一
相关试题推荐
Inthefollowingtext,somesentenceshavebeenremoved.ForQuestions41-45,choosethemostsuitableonefromthelist(A、B、C、
Theinventionofbothlabor-savingtoolsandtoolsofintelligenceisrarelyaccidental.Instead,itisusuallytheproductofh
Theinventionofbothlabor-savingtoolsandtoolsofintelligenceisrarelyaccidental.Instead,itisusuallytheproductofh
Theinventionofbothlabor-savingtoolsandtoolsofintelligenceisrarelyaccidental.Instead,itisusuallytheproductofh
Theinventionofbothlabor-savingtoolsandtoolsofintelligenceisrarelyaccidental.Instead,itisusuallytheproductofh
Thoughusuallyunintendedandoftenunrecognized,muchofbehavioralscienceisavalue-ladenenterprise.【F1】Researchquestions
Thoughusuallyunintendedandoftenunrecognized,muchofbehavioralscienceisavalue-ladenenterprise.【F1】Researchquestions
[A]Butscientistsarestillworkingtoimproveonthat,andamongthemissocialpsychologistAldertVrijoftheUniversityofP
[A]Notgivingbonustoemployeeswhodeserveit[B]Notgivingpositiveinformation[C]Notlinkingindividualjobstothebigpic
Videogamesgetabadpress.Manyareunquestionablyviolentand,ashasbeenthewaywithnewmediafromnovelstocomicbooks
随机试题
患者,男,72岁,反复咳嗽、咳痰20余年,并伴进行性呼吸困难10余年。因上呼吸道感染以上症状加重并出现意识模糊1天。查体:BP100/60mmHg,口唇发绀,桶状胸,双肺叩诊呈过清音,呼吸急促,双肺可闻及细湿哕音,双下肢凹陷性水肿,病理反射未引出。X线检查
A、Becausehumanbeingsarepowerfulenoughtokilloneanother.B、Becauseeveryspecieswillbecomeextinctbynaturalselection
在数据库技术中,实体集之间的联系可以是一对一、一对多或多对多,那么“学生”和“课程”的联系为______________。
TheMinisterforCommunityDevelopmentthoughtlongandhardabouthowto______thesocialproblemsofthepoorareas.
下列关于一、二等重力点联测说法正确的是()。
“征免”栏应填()。
下列各项中,应在“预付账款”贷方核算的是()。
根据教学中使用的主要方法划分课的种类,可分为【】
“从严治警”的基本含义是对公安民警严格教育、严格训练、严格管理、严格纪律。()
方程f(x)=1有且仅有一个实根.(1)f(x)=|x-1|(2)f(x)=|x-1|+1
最新回复
(
0
)