Agriculture (a term which encompasses farming) is the process of producing food, feed, fiber, fuel and other goods by the systematic raising of plants and animals.
Agri is from Latin ager, meaning "a field", and culture is from Latin cultura, meaning "cultivation" in the strict sense of tillage of the soil. A literal reading of the English word yields: tillage of the soil of a field. In modern usage, the word Agriculture covers all activities essential to food/feed/fiber production, including all techniques for raising and processing livestock. Agriculture is also short for the study of the practice of agriculture—more formally known as agricultural science.
The history of agriculture is a major element of human history, and agricultural progress has been a crucial factor in worldwide social change, including the specialization of human activity: when farmers became capable of producing food beyond the needs of their own families, others in the tribe or nation or empire were freed to devote themselves to something other than food acquisition.
42% of the world's laborers are employed in agriculture, making it by far the most common occupation. However, agricultural production accounts for less than 5% of the Gross World Product (an aggregate of all Gross Domestic Products).[1]
The term "farming" covers a wide spectrum of agricultural production work. At one end of this spectrum is the subsistence farmer, who farms a small area with limited resource inputs, and produces only enough food to meet the needs of his/her family. At the other end is commercial intensive agriculture, including industrial agriculture. Such farming involves large fields and/or numbers of animals, large resource inputs (pesticides, fertilizers, etc.), and a high level of mechanization. These operations generally attempt to maximize financial income from produce or livestock.
Modern agriculture extends well beyond the traditional production of food for humans and animal feeds. Other agricultural production goods include cut flowers, ornamental and nursery plants, timber, fertilizers, animal hides, leather, industrial chemicals (starch, sugar, ethanol, alcohols and plastics), fibers (cotton, wool, hemp, and flax), fuels (methane from biomass, biodiesel) and both legal and illegal drugs (biopharmaceuticals, tobacco, marijuana, opium, cocaine).
The twentieth century saw massive changes in agricultural practice, particularly in agricultural chemistry. Agricultural chemistry includes the application of chemical fertilizer, chemical insecticides (see pest control), and chemical fungicides, soil makeup, analysis of agricultural products, and nutritional needs of farm animals. Beginning in the Western world, the green revolution spread many of these changes to farms throughout the world, with varying success.
Other recent changes in agriculture include hydroponics, plant breeding, hybridization, gene manipulation, better management of soil nutrients, and improved weed control. Genetic engineering has yielded crops which have capabilities beyond those of naturally occurring plants, such as higher yields and disease resistance. Modified seeds germinate faster, and thus can be grown in an extended growing area. Genetic engineering of plants has proven controversial, particularly in the case of herbicide-resistant plants.
Engineers may develop plans for irrigation, drainage, conservation and sanitary engineering, particularly important in normally arid areas which rely upon constant irrigation, and on large scale farms.
The packing, processing, and marketing of agricultural products are closely related activities also influenced by science. Methods of quick-freezing and dehydration have increased the markets for farm products (see food preservation and meat packing industry).
Animals, including horses, mules, oxen, camels, llamas, alpacas, and dogs, are often used to cultivate fields, harvest crops and transport farm products to markets. Animal husbandry refers to the breeding and raising animals for meat or to harvest animal products (like milk, eggs, or wool) on a continual basis. Mechanization has enormously increased farm efficiency and productivity in Western agriculture (see agricultural machinery).
Airplanes, helicopters, trucks and tractors are used in Western agriculture for seeding, spraying operations for insect and disease control, aerial topdressing and transporting perishable products. Radio and television disseminate vital weather reports and other information such as market reports that concern farmers. Computers have become an essential tool for farm management
2007-03-12 11:43:30
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answer #10
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answered by Anonymous
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