Integration of circular economy and zero-waste practices with hydroponics for sustainable agriculture

Combines circular economy principles with hydroponics to minimize resource waste and maximize crop productivity. Reuses water, nutrients, and organic by-products to support zero-waste, closed-loop agricultural systems. Reduces land, water, and chemical inputs while ensuring year-round, climate-resilient food production. Transforms agricultural waste into valuable inputs, enhancing efficiency, sustainability, and economic viability. Offers a scalable model for urban and peri-urban farming aligned with zero-waste and sustainability goals. The integration of circular economy (CE) and zero-waste principles into hydroponic agriculture offers a system-level pathway for addressing resource scarcity, nutrient losses, and environmental degradation associated with conventional linear farming. This study develops a structured conceptual and analytical framework that operationalizes CE principles within hydroponic systems through defined system boundaries, closed-loop resource configurations, and a multidimensional performance assessment model. The research employs system mapping, resource-flow analysis, and indicator structuring to translate circular design strategies into measurable environmental, operational, and economic metrics. Unlike prior reviews that primarily discuss conceptual alignment or isolated efficiency gains, this study contributes: (i) a system-boundary-based circular design taxonomy for hydroponic configurations, (ii) an integrated indicator set linking resource circulation efficiency, system stability, and economic resilience, and (iii) a comparative assessment logic distinguishing linear, partial recirculation, and near-zero discharge systems. The analytical results show that circular hydroponic configurations improve resource retention through continuous nutrient recirculation and controlled dosing, minimize discharge via closed-loop management, and enhance operational stability when buffering capacities across water, nutrient, and energy subsystems are aligned. Secondary resource integration, including biomass valorisation and nutrient recovery, further increases system-level circularity and reduces external input dependency. The study identifies capacity balance and feedback control as critical determinants of sustainability performance in tightly coupled bio-physical production systems. By shifting evaluation from yield maximization to resource productivity, variability management, and value retention, the proposed framework advances sustainability assessment in hydroponic agriculture. The resulting model provides a transferable analytical foundation for circular system design, resilience enhancement, and policy-supported scaling of climate-adaptive food production systems.