Aquaponics: High-tech Agriculture Goes Urban
Aquaponics and Hydroponics farming requires less water and less land than traditional field farming. Long a niche technology existing in the shadow of conventional growing methods, hydroponics is getting a second look from university researchers and public health advocates.
Supporters point to the environmental cost of trucking produce from farms to cities, the loss of wilderness for farmland to feed a growing world population, and the risk of bacteria along extensive, insecure food chains as reasons for establishing urban hydroponic farms.However, the expense of setting up the high-tech farms on pricey city land and providing enough year-round heat and light could present some insurmountable obstacles.
The roots of hydroponically produced fruits and vegetables can dangle in direct contact with water or be set in growing media such as sponges or shredded coconut shells. Most commercial operations pump water through sophisticated sensors that automatically adjust nutrient and acidity levels in the water.
Hydroponics are generally used for fast-growing, high-value crops such as lettuces and tomatoes that can be produced year-round in heated, well-lit greenhouses. So far, production is not large enough for the U.S. Department of Agriculture to track. The country's largest hydroponic greenhouse is Eurofresh Inc.'s 274-acre operation in southeastern Arizona, where more than 200 million pounds of tomatoes were produced in 2007. Most large-scale commercial operations are in the arid Southwest, where water-efficiency is prized, or the sometimes frigid Northeast, where the method can be used year-round in heated greenhouses.
The technology has benefited from nearly three decades of NASA research aimed at sustaining astronauts in places with even less green space than a typical U.S. city.
This article is courtesy of www.cnn.com/2008/TECH/science/11/21/urban.agriculture.ap/index.html