Aquaculture developments raise issues of concern in terms of environmental impacts and ecosystem health. For aquaculture systems to be sustainable, they should not cause damage to natural systems by critically increasing (e.g. nutrients) or decreasing the concentrations of natural substances (e.g. chlorophyll). Other potential impacts relate to increasing concentration of man-made substances, such as persistent chemicals and through physical disturbance leading to habitat changes.
Aquaponics is a food production system that combines soil-less vegetable growing (hydroponics) and fish farming (aquaculture) within a closed re-circulating system. This combination of food production methods (hydroponics and aquaculture) removes the problems associated with the individual production methods.
For aquaculture, the main problem with Recirculating Aquaculture Systems is the production of Nitrate rich waste water that must be treated or dumped, creating major environmental problems. For hydroponics, the main problem is the complete reliance on chemical fertilizers to grow the vegetables.
When both methods are combined in an aquaponic unit, the nutrient-rich wastewater from the fish tanks, which would normally need to be treated or dumped, is used as an organic fertilizer for plant production. In turn, this removes the need for chemical fertilizers for plant growth using hydroponics.
Advantages for Aquaponic Food Production:
- Uses organic waste as the plant fertilizer
- Uses natural pest controls
- Tends to produce better tasting and at times more nutritional crops
- Potential for year-round production if growing environment can be controlled (i.e. greenhouse)
- Imitates a natural eco-system thus making it a highly sustainable food production method
- Increasing population & Urbanization
- Declining land agricultural productivity
- Increasing demand for healthy, pesticide free produce
It is considered that the model multi-use aquaponics production platforms have socioeconomic and environmental impacts on aquaculture, recreational fishing, yachting and boating and other water-based activities. They also have an impact on land-based activities, agricultural tourism, water waste management, regional employment (direct and indirect) and training opportunities.
