Decoupled aquaponics – Innovative food production systems for a sustainable nitrogen management

Aquaponics offers an innovative approach to reduce nitrogen emissions and the use of N-fertilizer for the combined production of fish and plants in closed production systems. Here, the savings potential of a conventional hydroponic lettuce production using conventional nutrient solution in comparison with decoupled aquaponics using the nutrient rich fish water as basis for the nutrient solution was evaluated. The use of fish water saved 85 % CAN fertilizer in comparison to the control without differences in growth. This study clearly demonstrates the huge potential of decoupled aquaponics to foster the transformation of conventional agriculture towards sustainable production systems saving resources and minimizing emissions.

Decoupled aquaponic systems have the potential to become one of the most effective production systems for the combined production of animal protein and plant crops. Here, recirculating aquaculture systems for fish production are combined with hydroponics for soilless plant production thereby recycling dissolved nutrients derived from metabolism of the fish (Monsees et al. 2019).