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Panoramic view of Ötlingen from the southeast; the hilly landscape is typical for the region ofMarkgräflerland
Agriculture is the practice of cultivating the soil, planting, raising, and harvesting both food and non-food crops, as well aslivestock production. Broader definitions also includeforestry andaquaculture. Agriculture was a key factor in the rise ofsedentary humancivilization, whereby farming ofdomesticated plants and animals created foodsurpluses that enabled people to live in the cities. While humans started gathering grains at least 105,000 years ago, nascent farmers only began planting them around 11,500 years ago. Sheep, goats, pigs, and cattle were domesticated around 10,000 years ago. Plants were independently cultivated in at least 11 regions of the world. In the 20th century,industrial agriculture based on large-scalemonocultures came to dominate agricultural output.
As of 2021[update],small farms, of which the vast majority are one hectare (about 2.5 acres) or smaller, produce about one-third of the world's food. Moreover, five of every six farms in the world consist of fewer than 2 hectares (4.9 acres) and take up only around 12% of all agricultural land. In terms of total land use, large farms are dominant. While only 1% of all farms globally are greater than 50 hectares (120 acres), they encompass more than 70% of the world's farmland. Further, nearly 40% of all global agricultural land is found on farms larger than 1,000 hectares (2,500 acres).
Farms and farming greatly influencerural economics and greatly shaperural society, affecting both the directagricultural workforce and broaderbusinesses that support the farms and farming populations.
The major agricultural products can be broadly grouped intofoods,fibers,fuels, andraw materials (such asrubber andtimber). Food classes includecereals (grains),vegetables,fruits,cooking oils,meat,milk,eggs, andfungi. Global agricultural production amounts to approximately 11 billion tonnes of food, 32 million tonnes of natural fibers and 4 billion m3 of wood. However, around 14% of the world's food is lost from production before reaching the retail level.
Modernagronomy,plant breeding,agrochemicals such aspesticides andfertilizers, and technological developments have sharply increasedcrop yields, but also contributed toecological and environmental damage.Selective breeding and modern practices inanimal husbandry have similarly increased the output of meat, but have raised concerns aboutanimal welfare and environmental damage. Environmental issues includecontributions to climate change, depletion ofaquifers,deforestation,antibiotic resistance, andother agricultural pollution. Agriculture is both a cause of and sensitive toenvironmental degradation, such asbiodiversity loss,desertification,soil degradation, andclimate change, all of which can cause decreases in crop yield.Genetically modified organisms are widely used, althoughsome countries ban them. (Full article...)
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, theAmerican 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, reflectingurban heat islands by showing the downtown areas of several cities (e.g.,Baltimore, Maryland,Washington, D.C. andAtlantic 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 theNational Arboretum websites still present the 1990 map as current. In 2006, the USNational 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. (Full article...)
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