While not directly related to environmental matters, the topic of this article does fit nicely under the umbrella of Sustainable Economic Development. And if you keep reading until the end of the article, see if you agree with my idea for commercial-scale economic development opportunities at former mountaintop removal mining sites.
No soil, no fertilizer, no problem!
Aquaponics is the combination of aquaculture (raising fish in tanks) and hydroponics (growing plants in water) so that both grow better. In aquaponics, you grow fish and plants together in one integrated, soilless system. The fish waste provides a natural fertilizer source for the plants and the plants provide a natural filter for the water the fish live in. Aquaponics produces safe, fresh, organic fish and vegetables. When aquaponics is combined with a controlled environment greenhouse, premium quality crops can be grown on a year-round basis, anywhere in the world. Aquaponics can be used to sustainably raise fresh fish and vegetables for a family, to feed a town or to generate a profit in a commercial farming venture.
■ Aquaponics uses less than 2% of the water that traditional farming does.
■ Aquaponics is energy-efficient: current systems use one-tenth of the energy conventional farming does.
■ Aquaponics has eight to ten times more vegetable production in the same area and time.
■ Aquaponics is fully scalable from backyard family systems to full commercial systems.
■ Aquaponics produce can be USDA Certified Organic and Food Safety Certified.
Commercial-Scale Aquaponics Research
A graduate student at the SUNY College of Environmental Science and Forestry (ESF) is conducting a first-of-its kind experiment in urban food production, using dried food waste to raise fish and using the fish waste to nourish an ever-growing crop of Boston Bibb lettuce.
"The idea is that you're taking post-consumer food waste," said Michael Amadori, a master's student in ecological engineering, "and you are growing fish, then you're taking fish waste and you're growing lettuce."
"The whole idea with aquaponics is sustainability," he said. "You can grow fresh food in non-traditional areas, such as college campuses and the urban environment." Amadori said this is the first time anyone has experimented with using post-consumer food waste to feed the fish.
If he's successful, he will have found a way to reduce the amount of food that enters the waste stream while also devising a way to significantly lower the cost of growing fish commercially.
"Not only is Michael investigating the nutrient and energy flows in this system, he is designing a system that can be scaled up for use in small communities that have suffered economic hardship from the loss of manufacturing jobs, such as paper mill closures in the northeastern United States," said Douglas J. Daley, director of the ESF-based SUNY Center for Brownfield Studies and Amadori's major professor.
Amadori's experiment is set up in a greenhouse on the ESF campus. Six 55-gallon plastic barrels serve as tanks that each hold 20 young tilapia. In the early weeks of Amadori's work, the 120 fish together weighed less than a pound. When his experiment is complete in approximately a year, he expects them to attain commercial weight of one pound each.
The food waste is obtained from the dining center. "It's what's left on people's plates," he said. "Or it's left on the grill at the end of the day." He puts the food waste through a food grinder, dries it in an oven and breaks it into tiny pellets.
Fish in three of the tanks are fed the homemade pellets. The fish in the other three barrels eat commercial fish food so Amadori can compare the differences between the two populations.
Temperature-controlled water from the fish tanks is pumped into plastic containers in which rows of Boston Bibb lettuce grow in beds of gravel. There is no soil. The lettuce absorbs the nutrients from the fish waste and the water is cycled back into the tanks. The process continues around the clock.
Amadori said he is using tilapia because they are hardy enough to withstand changes in pH and temperature and because the mild-tasting fish have emerged as a popular menu item in the last few years.
He said the tilapia grown at fish farms is typically fed with fish that are harvested in the ocean and processed into commercial fish food. "It's extremely unsustainable," he said. "We can close the loop with this process," Amadori said. "One thing we have plenty of in an urban environment is food waste."
Economic Development Opportunities
Aquaponics is well-suited to non-traditional agricultural areas, since it requires no tillable soil and minimal amounts of fresh water. It consumes only moderate quantities of energy, chiefly to heat the buildings, along with electricity for lighting, water heating and water pumps.
A particularly appealing site for commercial-scale aquaponics is former surface mines, especially mountaintop removal mining sites such as those found in West Virginia and Kentucky. These sites would already have most, if not all, of the infrastructure elements required for a commercial aquaponics farming operation – road (and often nearby rail) transportation, electricity, natural gas, fresh water and flat terrain for building sites. In addition to the aquaponics farming operation, former mountaintop removal mining sites would also be good candidates for processing plants to manufacture fish food from non-traditional sources, such as food waste from schools, hospitals, restaurants and supermarkets.
For further information onaquaponics, see the following:
ESF Grad Student Puts a New Twist on Aquaponics: http://www.esf.edu/communications/view.asp?newsID=1030
Aquaponics Journal: http://www.aquaponicsjournal.com/
Backyard-Scale Aquaponics: http://www.nytimes.com/2010/02/18/garden/18aqua.html
This article was partially excerpted from publically available information, and was authored by Rick Wilson, Acacia Environmental Group LLC. Any opinions expressed in this article are those solely of the author, and are not intended as legal or professional guidance to any specific readers. For more information on the author see here.