Aquaponics as an integrated agri-aquaculture system (IAAS): Emerging trends and future prospects

Aquaponics, an integrated agri-aquaculture system, is an interdisciplinary approach that addresses the water-food-energy nexus of United Nations' sustainable development goal and increasing demands of global population at minimal ecological cost. Embracing the ‘circular bio-based economy’ concept, aquaponics has exhibited immense potential for reduced resource utilization, discharge mitigation, nutrient, energy, wastewater recycling, and production of highly nutritious food within the system. Aquaponics has attained increased public interest in recent years in urban areas, in line with the trend towards greater productivity with limited resources, diving it from small-scale operation to brink of commercialization. The holistic analysis of scientific articles on aquaponics has perceived the transition of research trends from optimization of system performance (component ratio, hydraulic loading rate, etc.) to adoption of marine, inland saline, decoupled aquaponics and nutrient management to address challenges like freshwater scarcity, depleting marine resources, salinization, nutrient deficiency for plants, etc.; yet a constructive scientific concept is still limited. Marine, inland saline, and decoupled aquaponics has increasingly gained popularity in last decades, yet further expansion is demanded as a way forward to tackle the global challenges. This article provides insight into the prevailing state-of-art with recommendations for future orientation of research for developing this sustainable production technology.