Is Integrated Multi-Trophic Aquaculture-Rice Co-Culture an Unrealistic or Feasible Approach to Providing Essential Crops, Optimizing Feed Conversion Ratio, Nitrogen and Phosphorus Use Efficiency?

Abstract Rice is not a horticultural crop, thus the idea that indoor cultivation cannot compete with outside production in desert and non-urban areas with shortages of water and challenging cultivation circumstances. The study intends to offer critical crops to poor communities through small-scale aquaponics systems that can adapt to climate change, despite some doubts about its feasibility. This study investigates the potential of integrated agriculture-aquaculture systems (IAAS) to enhance water, nitrogen, and phosphorus use efficiency (WUE, NUE, and PUE) while extending the nutrient cycle for rice and aquatic animal culture under climate adaptation conditions using greenhouses. This trial contained four treatments administered over 90 days. Two types of tilapia (T)-rice (R) co-culture systems and integrated multi-trophic-aquaculture (IMTA)-rice (R) co-culture systems were evaluated using two rice hydroponic culture techniques: floating raft system (FRS, T-R-FRS, and IMTA-R-FRS) and nutrient film technique (NFT, IMTA-R-NFT, and T-R-NFT). All treatments were carried out in two independent greenhouses equipped with indoor recycling closed systems and 10 kW solar panels. The FRS-R-IMTA system has superior rice properties compared to the NFT system. IMTA-R aquaponic and tilapia-R monoculture systems can reduce nutrients and water waste while increasing crop yields. These represent a potential solution to the challenges of climate change, which necessitates a more sustainable and resilient food production system. The IMTA system’s apparent FCR values (0.73) surpass those of the tilapia monoculture system (1.58). IMTA-developed technology enables farmers to profitably culture a diverse species of aquatic animals without the need for costly extra feed. The results showed that coupled IMTA-R and T-R using the FRS technique are more promising for optimizing NUE and PUE efficiency than the NFT technique, as well as for producing a wider range of aquatic animals (such as mullets, crayfish, freshwater clams, and silver carp) than the T-R-FRS.