Roots of Aquaponics
INTRODUCTION
Aquaponics is
a combination of aquaculture and hydroculture which includes elements of
recurculation and symbiosis(1),its gives
output of vegetables and fishes utilizing water which is nutrient rich and fish
food and excreata as a basic source,again it is a soilless culture. History
says that one of the ancient practice is using fish waste as fertilizer for
crops.”stationary islands” set up in shallow lakes in central
America(e.g.,Aztec’s Chinampas 1150-1350
BC)2. In South East Asia about 1500 years ago used to introduction of
fish into paddy fields3 ,researchers at the New
Alchemy Institute North Carolina State University (USA) in 70’s and early 80’s
developed the basics of modern Aquaponics4. Good mile stone was set up in year
1980 at the University of the Virgin
Island(UVI) 1.A survey, conducted by Love et
al. 4, shows that
aquaponics has been receiving growing interest since then 5, which point out
its increasing food security for society.
Food security would be particularly
belongs to global population it now exceeds 7.2billions and is growing rapidly 9.6
billions around 2050.6Urban population growth will require an increasing
demand for animal protein7.
Aquaculture is
closed system of fish farming, where commercial fishes (catfish,ornamental
fish,cray fish or prawns etc.)are grown under controled conditions in container.
It includes a new aproach called recirculating aquaculture system (RAS), reuse of water with
< 10% of total water volume replaced per day8.
Hydroponics is a term used to
determine the production of plants in soilless media. Plant roots plays major
role in a nutrient artificial medium for mechanical support 9.It supports the
production of green leaf vegetables Chinese
cabbage,lettue,basil,spanich,chilles.
In other hand aquaponics system with
mature and high stock density of fish,plants such as tomato, peppers and
cucumbers.it includes salads capsicum,red salads
onions,snowpeas,okra,tomato,bellpepper.
To full fill the concept of aquaponics
living microbial concept comes a head
that is symbiosis (nitrification).
Nitrification, a two-step process;
First step ammonia is oxidized to nitrite, 2 NH4+ + 3 O2 ? 2 NO2? + 2 H2O + 4 H+ (Nitrosomonas)
Second step nitrite
is oxidized to nitrate.
2 NO2? + O2 ? 2 NO3? (Nitrobacter, Nitrospira)