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Agriculture

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Farming, ploughing rice paddy, in Indonesia
Farming, ploughing rice paddy, in Indonesia

Agriculture is the process of producing food, feed, fiber and other desired products by cultivation of certain plants and the raising of domesticated animals (livestock). Agriculture is also known as farming.

Contents

Overview

Rice fields in Java, Indonesia
Rice fields in Java, Indonesia

Agriculture includes—

  • subsistence agriculture, which is producing enough food to meet the needs of the farmer/agriculturalist and family (but no more)
  • (almost universally in the "developed" nations and increasingly so in other areas) the production of financial income from cultivation of the land or commercial raising of animals (animal husbandry), or both.

Agriculture is the practice—the study of these disciplines is called agricultural science.

Increasingly, besides food for humans and animal feeds, agriculture produces goods such as cut flowers, ornamental and nursery plants, timber or lumber, 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). Genetically engineered plants and animals produce specialty drugs.

In the Western world, use of genetics, better management of soil nutrients and improved weed control have greatly increased yields per unit area. At the same time, use of mechanization has decreased labor requirements, releasing most of the populace from intense agricultural labor. The developing world is behind by Western measures of productivity because of unavailability of the education, capital and technology base needed to sustain these advances, and usually ecoregion with less optimal climates and soils.

Modern agriculture depends heavily on engineering and technology and on the biological and physical sciences. Irrigation, drainage, conservation and sanitary engineering—each of which is important in successful farming—are some of the fields requiring the specialized knowledge of agricultural engineers.

Agricultural chemistry deals with other vital farming concerns, such as the application of fertilizer, insecticides (see Pest control), and fungicides, soil makeup, analysis of agricultural products, and nutritional needs of farm animals.

Plant breeding and genetics contribute immeasurably to farm productivity. Genetics has also made a science of livestock breeding. Hydroponics, a method of soilless gardening in which plants are grown in chemical nutrient solutions, may help meet the need for greater food production as the world's population increases.

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 Processing and Preservation; Meat Packing Industry).

Mechanization, the outstanding characteristic of late 19th- and 20th-century agriculture, has eased much of the backbreaking toil of the farmer. More significantly, mechanization has enormously increased farm efficiency and productivity (see Agricultural Machinery). Animals, including horses, mules, oxen, camels, llamas, alpacas, and dogs; however, are still used to cultivate fields, harvest crops and transport farm products to markets in many parts of the world.

Airplanes, helicopters, trucks and tractors are used in agriculture for seeding, spraying operations for insect and disease control, transporting perishable products, and fighting forest fires. 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.

Animal husbandry means breeding and raising animals for meat or to harvest animal products (like milk, eggs, or wool) on a continual basis.

In recent years some aspects of industrial intensive agriculture have been the subject of increasing discussion. The widening sphere of influence held by large seed and chemical companies, meat packers and food processors has been a source of concern both within the farming community and for the general public. There has been increased activity of some people against some farming practices, raising chickens for food being one example. Another issue is the type of feed-stock given to some animals that can cause Bovine Spongiform Encephalopathy in cattle.

The patent protection given to companies that develop new types of seed using genetic engineering has allowed seed to be licensed to farmers in much the same way that computer software is licensed to users. This has changed the balance of power in favor of the seed companies, allowing them to dictate terms and conditions previously unheard of. Some argue these companies are guilty of biopiracy.

Soil conservation and nutrient management have been important concerns since the 1950s, with the best farmers taking a stewardship role with the land they operate. However, increasing contamination of waterways and wetlands by nutrients like nitrogen and phosphorus are of concern in many countries.

Increasing consumer awareness of agricultural issues has led to the rise of community-supported agriculture, local food movement, slow food, and commercial organic farming, though these yet remain fledgling industries.

History

Determining the origin of agriculture is problematic since it pre-dates writing. Some authorities insist localized farming took place more than 10,000 years ago, while others believe the earliest systematic plantings/harvestings took place no more than 7,000 years ago. The practice of agriculture is often used to distinguish the neolithic period from earlier parts of the stone age.

The first crops that humans domesticated included wheat, (einkorn and emmer), and barley. It is clear that farming was invented at least twice, probably more often. Once in the Fertile Crescent, (some say by the Natufian culture others say by the Sumerians), once in East Asia (rice) and once in Central America (maize, squash). Most certainly there was a gradual transition from a hunter-gatherer economy to an agricultural one via a lengthy period when some crops were deliberately planted and other foods were gathered from the wild. The reasons for the earliest introduction of farming may have included climate change.

Farming allows a much greater density of population than can be supported by hunting and gathering. It also allows the accumulation of excess product to keep for winter use or to sell for profit. The ability of farmers to feed large numbers of people whose activities have nothing to do with food production was the crucial factor in the rise of standing armies.

After 1492 the world'Columbian_Exchange" title ="Columbian Exchange">Columbian Exchange. Crops and animals that were previously only known in the Old World were now transplanted in the New and vice versa.

Policy

Agricultural policy focuses on the goals and methods of agricultural production. At the policy level, common goals of agriculture include:

  • Food safety: Ensuring that the food supply is free of contamination.
  • Food security: Ensuring that the food supply meets the population's needs.
  • Food quality: Ensuring that the food supply is of a consistent and known quality.
  • Conservation
  • Environmental impact
  • Economic stability

Methods

Crops

World production of major crops in 2002

In millions of metric tons, based on USDA estimates:

Maize 624
Wheat 570
Rice 381.1
Cotton 96.5

However, grazing grass and animal feed-crop production must exceed the total of those four crops.

Paddy rice is rice in its as-harvested state. Milled rice is rice after it is processed to remove the husk and to, sometimes, polish the kernel. California is the major US producer of rice but Thailand and Indonesia are the major producers in the world.

Crop improvement

An agriculural scientist records corn growth
An agriculural scientist records corn growth

Domestication of plants is done in order to increase yield, improve disease resistance and drought tolerance, ease harvest and to improve the taste and nutritional value and many other characteristics. Centuries of careful selection and breeding have had enormous effects on the characteristics of crop plants. Plant breeders use greenhouses and other techniques to get as many as three generations of plants per year so that they can make improvements all the more quickly.

Plant selection and breeding in the 1920s and 'Pasture" title ="Pasture">pasture (grasses and clover) in New Zealand. Extensive radiation mutagenesis efforts (i.e. primitive genetic engineering) during the 1950s produced the modern commercial varieties of grains such as wheat, corn and barley.

For example, average yields of corn (maize) in the USA have increased from around 2.5 tons per hectare (40 bushels per acre) in 1900 to about 9.4 t/ha (150 bushels per acre) in 2001, primarily due to improvements in genetics. Similarly, worldwide average wheat yields have increased from less than 1 t/ha in 1900 to more than 2.5 t/ha in 1990. South American average wheat yields are around 2 t/ha, African under 1 t/ha, Egypt and Arabia up to 3.5 to 4 t/ha with irrigation. In contrast, the average wheat yield in countries such as France is over 8 t/ha. Higher yields are due to improvements in genetics, as well as use of intensive farming techniques (use of fertilizers, chemical pest control, growth control to avoid lodging).

[Conversion note: 1 bushel (q) of wheat = 60 pounds (lb) ≈ 27.215 kg. 1 bushel of corn = 56 pounds ≈ 25.401 kg]

Very recently, genetic engineering has begun to be employed in some parts of the world to speed up the selection and breeding process. The most widely used modification is a herbicide resistance gene that allows plants to tolerate exposure to glyphosate, which is used to control weeds in the crop. A less frequently used but more controversial modification causes the plant to produce a toxin to reduce damage from insects (c.f. Starlink).

There are specialty producers who raise less common types of livestock or plants.

Aquaculture, the farming of fish, shrimp, and algae, is closely associated with agriculture.

Apiculture, the culture of bees, traditionally for honey—increasingly for crop pollination.

See also : botany, List of domesticated plants, List of vegetables, List of herbs, List of fruit

Environmental problems

See also

External links


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