Agriculture and agronomy portal
Agriculture is the cultivation of land and breeding of animals and plants to provide food, fiber, medicinal plants and other products to sustain and enhance life. Agriculture was the key development in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that enabled people to live in cities. The study of agriculture is known as agricultural science. The history of agriculture dates back thousands of years; people gathered wild grains at least 105,000 years ago and began to plant them around 11,500 years ago before they became domesticated. Pigs, sheep, and cattle were domesticated over 10,000 years ago. Crops originate from at least 11 regions of the world. Industrial agriculture based on large-scale monoculture has in the past century come to dominate agricultural output, though about 2 billion people worldwide still depend on subsistence agriculture.
Modern agronomy, plant breeding, agrochemicals such as pesticides and fertilizers, and technological developments have sharply increased yields from cultivation, but at the same time have caused widespread ecological and environmental damage. Selective breeding and modern practices in animal husbandry have similarly increased the output of meat, but have raised concerns about animal welfare and environmental damage through contributions to global warming, depletion of aquifers, deforestation, antibiotic resistance, and growth hormones in industrially produced meat. Genetically modified organisms are widely used, although they are banned in several countries.
The major agricultural products can be broadly grouped into foods, fibers, fuels, and raw materials (such as rubber). Classes of foods include cereals (grains), vegetables, fruits, oils, meat, milk, and eggs. Over one-third of the world's workers are employed in agriculture, second only to the service sector, although the number of agricultural workers in developed countries has decreased significantly over the past several centuries.
|(Pictured left: USDA Hardiness Zones in North America)
A hardiness zone (a subcategory of Vertical Zonation) is a geographically defined area in which a specific category of plant life is capable of growing, as defined by climatic conditions, including its ability to withstand the minimum temperatures of the zone (see the scale on the right or the table below). For example, a plant that is described as "hardy to zone 10" means that the plant can withstand a minimum temperature of -1°C. A more resilient plant that is "hardy to zone 9" can tolerate a minimum temperature of -7°C. First developed for the United States by the Department of Agriculture (USDA), the use of the zones has been adopted by other nations.
Based on the average annual minimum temperature for a given location, the USDA map provides an easy guideline for categorizing locations suitable for winter survival of a rated plant in an "average" winter. Since temperatures in the non-coastal-adjacent areas of the continent rarely present a consistent experience from year to year, and occasionally present a major—and often agriculturally devastating—deviation from the average minimum, the map has limitations for much of the country as a basis for using with long-term reliability, at least in areas close to the margin of a plant's rated hardiness-zone.
In 2003, the American Horticultural Society (AHS) produced a draft revised map, using temperature data collected from July 1986 to March 2002. This was a period of warmer winters than the 1974–1986 period, especially in the eastern U.S.A. The 2003 map placed many areas approximately a half-zone higher (warmer) than the 1990 map had. Reviewers noted the map zones appeared to be closer to the original 1960 map in its overall zone delineations. The 2003 AHS draft map purported to show finer detail, for example, reflecting urban heat islands by showing the downtown areas of several cities (e.g., Baltimore, Maryland, Washington, D.C. and Atlantic City, New Jersey) as a full zone warmer than outlying areas. The map excluded the detailed a/b half-zones introduced in the 1990 map, an omission widely criticized by horticulturists and gardeners due to the coarseness of the resulting map. The USDA rejected the AHS 2003 draft map; the agency stated it would create its own map in an interactive computer format. As of August 2010 the AHS and the National Arboretum websites still present the 1990 map as current. In 2006, the US National Arbor Day Foundation completed an extensive updating of U.S. Hardiness Zones. It used essentially the same data as the AHS. Once the Foundation analyzed the new data, it revised hardiness zones, reflecting the generally warmer recent temperatures in many parts of the country. The Foundation's 2006 map appears to validate the data used in the AHS 2003 draft. The Foundation also did away with the more detailed a/b half-zone delineations.
Sustainable agriculture is the practice of farming using principles of ecology, the study of relationships between organisms and their environment. It has been defined as "an integrated system of plant and animal production practices having a site-specific application that will last over the long term:
Sustainable agriculture in the United States was addressed by the 1990 farm bill. More recently, as consumer and retail demand for sustainable products has risen, organizations such as Food Alliance and Protected Harvest have started to provide measurement standards and certification programs for what constitutes a sustainably grown crop.
Categories: Sustainable agriculture, Sustainability
Did you know...
Agriculture and agronomy journals
Things you can do
Here are some tasks awaiting attention:
- Article requests : Fish production principles
- Expand : Agricultural land, Agricultural cycle, Agricultural education, Agrobiology, Agronomist, Agroforestry, Food and Agriculture Organization, Agricultural organization, Fungiculture, Fodder, Fish emulsion, more...
- Photo : Fungiculture, Nematodes
- Verify : Agriculture, forestry, and fishing in Japan
- Other : Categories to cleanup: Category:Agriculture
- – When a task is completed, please remove it from the list.
- Select [►] to view subcategories
- Select [►] to view subcategories