Waste production and valorization in an integrated aquaponic system with bester and lettuce

Abstract

The purpose of this study was to characterize the wastewater effluent emerging from sturgeon aquaculture and to evaluate its potential for hydroponic lettuce production. Bester sturgeon and Lactuca sativa were used to test both nitrogen excretion and uptake in an aquaponic system under two hydraulic regimes. In the end of the experiment, fish growth performance, lettuce yields and nutrient retention were assessed. Higher ammonia excretion for sturgeons held in higher hydraulic retention time (HRT) was found. Similarly, lettuce registered greater amount of both biomass and yield in lower flow treatment. In terms of wastewater treatment efficiency, lower nitrate removal rate and higher total ammonia nitrogen (TAN) removal rate occurred in high flow rate treatments.

Key words: Phytoremediation, recirculating aquaculture, raft hydroponics, Lactuca sativa.