Abstract
Aquaponics
is a bio-integrated system that links recirculating aquaculture with
hydroponic vegetable,
flower or herb production. Recent advances by researchers
and
growers alike have turned
aquaponics into a working model of sustainable food production. This
publication provides
an overview of aquaponics with brief
profiles
of working units around the country. An extensive
list of resources point the reader to print and web-based
educational materials for further
technical assistance.
Introduction
Aquaponics,
also known as the integration of hydroponics with aquaculture, is
gaining increased
attention as a bio-integrated food production system. Aquaponics
helps
production agriculture
meet its goals of sustainability by following certain
principles:
The
waste products of one system serve as food or fuel for a second
biological system.
The integration of fish and plants is a type of polyculture that
increases diversity
and
thereby enhances system stability Biological water filtration
removes nutrients
from water before it leaves the system Sale of greenhouse products
generates
income
which
supports the local economy.
ZERO WASTE THEORY
Instead
of locating the fish and vegetable components in separate containers
inside a greenhouse,
fish production can be located in outdoor tanks or
adjacent
buildings.
The effluent simply
needs to be delivered to hydroponic vegetable beds. In warm climates, hydroponic
vegetable
beds may be located outside. As
an
example, the Center for Regenerative Studies at California
State Polytechnic University-Pomona implemented an outdoor
integrated bio-system that
links:
(a)
a pond containing treated sewage wastewater stocked with tilapia and
carp; (b) water
hyacinth - an aquatic plant very efficient at sucking up nutrients -
covering
50% of the water
surface area; the plant biomass generated by water hyacinth is used
as feedstock for compost
heaps; (c) nearby vegetable gardens
irrigated
with nutrient-laden pond water.
In
addition to locating the fish and vegetable components in separate
containers, fish and plants can
be placed in the same container to function as a polyculture.
For
example, plants sit on top of
floating polystyrene panels with their roots hanging down into the
water that fish swim around
in. Models include the Rackocy
system,
solar-algae ponds (see literature by Zweig and Kleinholz),
and the solar-aquatic ponds, or Living Machines, made popular by
John Todd at Ocean
Arks
International.
