Aquaponic systems are becoming increasingly popular, even in urban contexts. Is it just a fad or could they actually become the future of sustainable farming?
By Rahmita Wirza & Shah Nazir
Aquaponic systems are a combination of aquaculture and hydroponics, meaning that plants and fish (and/or crustaceans) are grown together in one integrated system, that is, usually a tank filled with water. In agriculture, aquaponic systems are considered a sustainable way of food production as they follow circular economy principles, reducing input and waste.
In community gardens and urban farms, where they are becoming increasingly popular, aquaponic systems present themselves with pros and cons.
From an environmental perspective, they considerably reduce the amount of water needed. In a regular fish tank, water has to be discharged frequently. In an aquaponics system, however, bacteria convert fish excretions into exploitable nutrients for the water plants. From an economic perspective, the integration of aquaculture and hydroponics into one functioning system requires a considerable investment, at least in the beginning. From a social perspective, it is important to mention that aquaponics can secure the local cultivation of agricultural products – even in urban areas where cultivation of land is not possible. Aquaponics could thus contribute to community life and strengthen the economy.
Aquaponic system that involves tilapia or perch (up to 10,000 fish in the 5 ft deep tank), watercress and tomatoes. The water is drawn up through one pump and gravity fed through the potted plants (which remove the nitrogen from the fish waste) and back into the tank where it re-oxygenizes the tank water. (Image by Ryan Griffis via Wikimedia Commons/CC BY-SA 2.0)
The existing literature regarding aquaponic production methods covers different species of vegetables and fish, a variety of layouts of system, as well as climate conditions. However, there is currently a lack of knowledge that systematically summarizes the existing state-of-the-art work.
In order to change this, a recent article in Reviews on Environmental Health, now presents a systematic literature review in the field of urban aquaponics. According to the authors from Malaysia and Pakistan, “This systematic review will help practitioners to take help from the existing literature and propose new solutions based on the available evidence on urban aquaponics.”
Only time will tell if aquaponics are the future of farming, but it is safe to say that the more we know, the better our chances are to find out.
If you are interested, you can learn more in the original article here:
Rahmita Wirza and Shah Nazir: Urban aquaponics farming and cities- a systematic literature review, 04.09.2020.
