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Intensive farming or intensive agriculture also known as industrial agriculture is characterized by a low fallow ratio and higher use of inputs such as capital and labour per unit land area.〔(Encyclopaedia Britannica's definition of Intensive Agriculture )〕〔(BBC School fact sheet on intensive farming )〕 This is in contrast to traditional agriculture in which the inputs per unit land are lower. Intensive animal husbandry involves either large numbers of animals raised on limited land, usually confined animal feeding operations (CAFO) often referred to as factory farms,〔〔(Factory farming. Webster's Dictionary definition of Factory farming )〕〔(Encyclopaedia Britannica's definition of Factory farm )〕 or managed intensive rotational grazing (MIRG). Both increase the yields of food and fiber per acre as compared to traditional animal husbandry. In a CAFO feed is brought to the animals, which are seldom moved, while in MIRG the animals are repeatedly moved to fresh forage. Intensive crop agriculture is characterised by innovations designed to increase yield. Techniques include planting multiple crops per year, reducing the frequency of fallow years and improving cultivars. It also involves increased use of fertilizers, plant growth regulators, pesticides and mechanization, controlled by increased and more detailed analysis of growing conditions, including weather, soil, water, weeds and pests. This system is supported by ongoing innovation in agricultural machinery and farming methods, genetic technology, techniques for achieving economies of scale, logistics and data collection and analysis technology. Intensive farms are widespread in developed nations and increasingly prevalent worldwide. Most of the meat, dairy, eggs, fruits and vegetables available in supermarkets are produced by such farms. Smaller intensive farms usually include higher inputs of labor and more often use sustainable intensive methods. The farming practices commonly found on such farms are referred to as appropriate technology. These farms are less widespread in both developed countries and worldwide, but are growing more rapidly. Most of the food available in specialty markets such as farmers markets is produced by these smallholder farms. ==History== Agricultural development in Britain between the 16th century and the mid-19th century saw a massive increase in agricultural productivity and net output. This in turn supported unprecedented population growth, freeing up a significant percentage of the workforce, and thereby helped enable the Industrial Revolution. Historians cited enclosure, mechanization, four-field crop rotation, and selective breeding as the most important innovations.〔 * Overton, Mark. (Agricultural Revolution in England 1500 - 1850 ) (September 19, 2002), BBC. * Valenze, Deborah. ''The First Industrial Woman'' (New York: Oxford University Press, 1995), p. 183. * Kagan, Donald. ''The Western Heritage'' (London: Prentice Hall, 2004), p. 535-9.〕 Industrial agriculture arose along with the Industrial Revolution. By the early 19th century, agricultural techniques, implements, seed stocks and cultivars had so improved that yield per land unit was many times that seen in the Middle Ages. The industrialization phase involved a continuing process of mechanization. Horse drawn machinery such as the McCormick reaper revolutionized harvesting, while inventions such as the cotton gin reduced the cost of processing. During this same period, farmers began to use steam-powered threshers and tractors, although they were expensive and dangerous. In 1892, the first gasoline-powered tractor was successfully developed, and in 1923, the International Harvester Farmall tractor became the first all-purpose tractor, marking an inflection point in the replacement of draft animals with machines. Mechanical harvesters (combines), planters, transplanters and other equipment were then developed, further revolutionizing agriculture. These inventions increased yields and allowed individual farmers to manage increasingly large farms. The identification of nitrogen, potassium, and phosphorus (NPK) as critical factors in plant growth led to the manufacture of synthetic fertilizers, further increasing crop yields. In 1909 the Haber-Bosch method to synthesize ammonium nitrate was first demonstrated. NPK fertilizers stimulated the first concerns about industrial agriculture, due to concerns that they came with serious side effects such as soil compaction, soil erosion and declines in overall soil fertility, along with health concerns about toxic chemicals entering the food supply.〔 ebook ISBN 978-1-84593-289-3〕 The identification of carbon as a critical factor in plant growth and soil health, particularly in the form of humus, led to so-called ''sustainable agriculture,'' alternative forms of intensive agriculture that also surpass traditional agriculture, without side effects or health issues. Farmers adopting this approach were initially referred to as ''humus farmers'', later as ''organic farmers''. The discovery of vitamins and their role in nutrition, in the first two decades of the 20th century, led to vitamin supplements, which in the 1920s allowed some livestock to be raised indoors, reducing their exposure to adverse natural elements. Chemicals developed for use in World War II gave rise to synthetic pesticides. Following World War II, synthetic fertilizer use increased rapidly,〔(【引用サイトリンク】title=A Historical Perspective )〕 while sustainable intensive farming advanced much more slowly. Most of the resources in developed nations went to improving industrial intensive farming, and very little went to improving organic farming. Thus, particularly in the developed nations, industrial intensive farming grew to become the dominate form of agriculture. The discovery of antibiotics and vaccines facilitated raising livestock in CAFOs by reducing diseases caused by crowding. Developments in logistics and refrigeration as well as processing technology made long-distance distribution feasible. Between 1700 and 1980, "the total area of cultivated land worldwide increased 466%" and yields increased dramatically, particularly because of selectively bred high-yielding varieties, fertilizers, pesticides, irrigation and machinery. Global agricultural production doubled between 1820 1920; between 1920 and 1950; between 1950 and 1965; and again between 1965 and 1975 to feed a global population that grew from one billion in 1800 to 6.5 billion in 2002.〔Matthew Scully (Dominion: The Power of Man, the Suffering of Animals, and the Call to Mercy ) Macmillan, 2002〕 The number of people involved in farming in industrial countries dropped, from 24 percent of the American population to 1.5 percent in 2002. In 1940, each farmworker supplied 11 consumers, whereas in 2002, each worker supplied 90 consumers.〔 The number of farms also decreased and their ownership became more concentrated. In 2000 in the U.S., four companies produce 81 percent of cows, 73 percent of sheep, 57 percent of pigs, and produce 50 percent of chickens, cited as an example of "vertical integration" by the president of the U.S. National Farmers' Union.〔(Testimony by Leland Swenson ), president of the U.S. National Farmers' Union, before the House Judiciary Committee, September 12, 2000.〕 Between 1967 and 2002 the one million pig farms in America consolidated into 114,000〔 with 80 million pigs (out of 95 million) produced each year on factory farms, according to the U.S. National Pork Producers Council.〔 According to the Worldwatch Institute, 74 percent of the world's poultry, 43 percent of beef, and 68 percent of eggs are produced this way.〔(State of the World 2006 ) Worldwatch Institute〕 Concerns over the sustainability of industrial agriculture, which has become associated with decreased soil quality and over the environmental effects of fertilizers and pesticides have not subsided. Alternatives such as Integrated pest management (IPM), have had little impact because policies encourage the use of pesticides and IPM is knowledge-intensive.〔 These concerns sustained the organic movement and caused a resurgence in sustainable intensive farming and funding for the development of appropriate technology. Famines continued throughout the 20th century. Through the effects of climactic events, government policy, war and crop failure, millions of people died in each of at least ten famines between the 1920s and the 1990s. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「intensive farming」の詳細全文を読む スポンサード リンク
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