首页
登录
职称英语
The farm is a major marketplace for millions of tons of synthetic fertilizers
The farm is a major marketplace for millions of tons of synthetic fertilizers
游客
2023-12-23
24
管理
问题
The farm is a major marketplace for millions of tons of synthetic fertilizers and pesticides, and for advanced machinery and the fuel required to run it. The modern superfarm, large and highly capitalized, is resource dependent compared with the diversified small farms that were once dominant. On diversified farms, major energy needs may be supplied by resident humans and animals. Soil fertility may be maintained by alternating cash crops and restorative crops, and also by returning animal manure to the soil. This fanning model of relatively self-sufficient agriculture, and the way of life associated with it, are still economically viable, as demonstrated by prosperous Amish farmers and other practitioners of "alternative" agriculture. Particularly relevant to today’s mainstream agriculture are the energy-saving practices on large "organic" farms, which are thoroughly mechanized but which minimize the use of pesticides and synthetic fertilizers.
By comparison, mainstream American agriculture has until lately been careless in its use of energy, water, and land. When fossil energy was cheap, applications of fertilizers and pesticides paid large dividends, so farmers were encouraged to use these products. Soon most farmers used too much fertilizer and pesticide. Farmers in dry regions enjoyed an era of cheap water, obtained from publicly subsidized irrigation systems or from pumping groundwater using inexpensive energy. The soil too was expendable as demand grew for U.S. agricultural products.
The period of extraordinary profligacy in the use of soil, water, and fossil fuels may well be at an end. The new structure of large farms is quite sensitive to cost factors. These adaptive farms, whose development was assisted by public tax, subsidy and research policies, have access to capital, technologies, and management skills, enabling them to switch relatively quickly to resource-conserving practices—for example, to low-tillage system that requires less fuel, that shepherds soil moisture, and that may reduce soil erosion. It seems likely that federal programs that have enlarged our farms, therefore, have had a further result of creating the potential for a more conserving agriculture. With respect to energy use. for example, energy costs per unit of output are lower for large farms, mainly because these farms quickly economized on energy as costs rose. In the future, according to one authoritative assessment, "agricultural production is likely to use capital and land more intensively but energy, fertilizer and labor less intensively". [br] The main difference between the modem super farm and diversified farms lies in ______.
选项
A、their sizes
B、the machinery employed
C、the degree of dependence on resources
D、the kinds of crops cultivated and animals raised
答案
C
解析
转载请注明原文地址:https://tihaiku.com/zcyy/3298841.html
相关试题推荐
[originaltext]Everyoneknowsaboutunemployment.ButmillionsofworkingAm
[originaltext]Everyoneknowsaboutunemployment.ButmillionsofworkingAm
[originaltext]Everyoneknowsaboutunemployment.ButmillionsofworkingAm
MillionsofbooksandanInternet-basedcampusnetworkareavailablefortheUni
MillionsofbooksandanInternet-basedcampusnetworkareavailablefortheUni
[originaltext]Everyoneknowsaboutunemployment.ButmillionsofworkingAm
[originaltext]Everyoneknowsaboutunemployment.ButmillionsofworkingAm
[originaltext]Everyoneknowsaboutunemployment.ButmillionsofworkingAm
[originaltext]Everyoneknowsaboutunemployment.ButmillionsofworkingAm
TheNorthKoreahasmillionsofdollarsdepositedinaMacaubank.[br][origin
随机试题
Amerchant,whosedaughterhadmarriedamanwithwhomitprovedshecouldnotg
A. B. C. D. E.
下列隧道围岩初期支护说法正确的有()。A.Ⅰ、Ⅱ级围岩支护时,宜采用局部喷
水利安装工程工程量清单项目包括( )。A.围护设备安装工程 B.地质勘测安装
高压设备上工作需要全部停电或部分停电者应填用()工作票。 A.第一种
以下关于工作分析的说法正确的是()A.工作分析为企业战略的落实和组织结构的优
自律细胞自动兴奋频率的高低主要取决于 A.0期去极化速度B.4期自动去极化速
人民警察的辞退,是指公安机关对已不具备人民警察条件,不适合在公安机关继续工作的人
根据《水土保持法》,水土保持方案审批部门为( )以上人民政府水行政主管部门。A.
根据《防洪法》,防洪区是指洪水泛滥可能淹及的地区,分为()。A、泄洪区 B、洪
最新回复
(
0
)