Integrated nutritional management in aquaponic systems: modulating nitrogen excretion through specific dietary strategies

• Grant number: 24/19461-2
• Support Opportunities: Scholarships in Brazil - Master
• Start date: April 01, 2025
• End date: July 31, 2026
• Field of knowledge: Agronomical Sciences - Fishery Resources and Fishery Engineering - Aquaculture
• Principal Investigator: Brunno da Silva Cerozi
• Grantee: Josué Wenceslau de Oliveira Neto
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil

Abstract

The growth in global population is intensifying pressure on food production and agricultural intensification, exposing the environmental issues associated with traditional production systems. In this context, sustainable practices like aquaponics, which integrates fish and plant production in recirculating systems, have gained increasing importance. However, nutrient deficiencies and nitrate accumulation in the nutrient solution are recurrent challenges in aquaponics. This study proposes integrated nutritional management in aquaponic systems by reducing dietary protein levels and increasing feeding frequencies. Two experiments will be conducted with juvenile Nile tilapia fed twice and eight times per day with diets containing 26% and 32% crude protein. The first experiment will evaluate nutrient absorption and excretion rates in the fish, while the second will assess fish performance, plant biomass accumulation, and nutrient dynamics in the aquaponic system. This strategy is expected to improve nitrogen utilization efficiency in the fish, resulting in lower nitrogen excretion rates and a more balanced aquaponic nutrient solution, thereby enhancing plant productivity without compromising fish performance.