Urban Aquaculture

Urban Aquaculture

This article relates to On Such a Full Sea

Fan, the protagonist in On Such a Full Sea, works in a large fish tank. She tends to the fish that are being bred and makes sure the system is working in fine form. Such farms are part of B-Mor's economic system and the output they generate is shipped to the Charters beyond B-Mor's gates.

As the temperature of oceans continues to rise, creating unstable environments for large-scale fishing, and as the world population keeps increasing, fish farming or aquaculture, which can be done in oceans, ponds or tanks, has been increasingly used to supplement diets.

The two primary types of aquaculture include extensive aquaculture where the chemical composition of ponds is altered so as to increase the production of phytoplankton and correspondingly, increase the production of fish, and intensive aquaculture, which includes a variety of external methods to increase fish production. These can range from cages suspended in the water, with the fish fed aerated oxygen and food; to artificially carved ponds where fish are corralled and raised. All these methods have their critics, with many accusing fish farming of overuse of antibiotics and upsetting the ecosystems in which these fish are raised.

The method used in On Such a Full Sea most closely resembles what is known as urban aquaculture, one version of intensive aquaculture. At its most basic, urban aquaculture relies on a large tank to grow fish. The system is, of course, more complex, using an interesting symbiotic process to grow both fish and plants. Waste from the fish is used to fertilize the plants that grow at the top of the tanks and the plants in return filter the water for use by the fish.

These aquaculture systems have been increasing in use, especially in urban centers where space is scarce. In Chicago, a system called The Plant incorporates a four-story produce and fish farm. Using the principles of hydroponics (growing plants in water), the Plant includes 3,000 square-feet of lettuce, and tilapia in tanks. Essential to this system's maintenance is a 9,000-gallon water circulation system. The Plant goes one step further than the tanks at B-Mor: leftover vegetable and fish waste is converted to fertilizer and biogas and powers a small electrical system.

Similar methods (or parts of them) are in force in Brooklyn and Milwaukee. Among the many advantages of such a system are decreased transportation costs and the ability to bring fresh food to urban food deserts.

first photo credit: Dr. John Todd, Vermont-based scientist, author and entrepreneur, of self-sustaining aquaculture tanks.
second photo credit: Brent Baughman /NPR
third photo from: Sweet Water Organics urban aquaculture warehouse site, Milwaukee

Filed under Medicine, Science and Tech

This "beyond the book article" relates to On Such a Full Sea. It originally ran in January 2014 and has been updated for the December 2014 paperback edition. Go to magazine.