Environmental impact assessment of aquaponic vegetable production: initial results

Aquaponics is an innovative and sustainable production system that combines crop and fish cultivation with minimal chemical fertilisers input. Thus, the University of Thessaly established a pilot-scale aquaponics unit in which have implemented comparative studies of crop performance and yield under three production systems: hydroponics (HP), coupled aquaponic system (AQ, solution directly derived from the fish tanks) and decoupled aquaponic system (CAP, aquaponic solution enriched with nutrients through supplementation of fertilizers to reach the target values of HP). The CAP system has been consistently proved to promote plant physiology, growth and yield compared to the other two systems. The aim of this work was the comparative assessment of the environmental impacts caused during the production of cucumber crop grown under the above systems. The data used for the analysis were collected in the pilot aquaponic system of the University of Thessaly located in Velestino, Greece. The system consisted of an aquaculture system with a capacity of 9 m³ in which tilapia breeding was performed. The system was connected to a greenhouse cultivation area of about 300 m². Cucumber crop was cultivated for a period of about 6 months. Eighteen categories of environmental impacts were assessed using an equal number of indicators. The results showed that the use of the CAP aquaponic system offers the potential to reduce the environmental impacts of cucumber cultivation.