Abstract
Year-round production of high-quality green forage using resource-efficient technologies is an important challenge for sustainable livestock farming. This study developed and experimentally evaluated an automated multi-tier hydroponic system integrating a sapropel-based bioactive medium, recirculating irrigation, and energy-efficient LED lighting. Experimental trials were conducted using feed barley (Hordeum vulgare L.) during a 10-day cultivation cycle. Resource consumption was assessed under light in-tensities of 200, 300, and 400 μmol m−2 s−1, while biomass productivity was evaluated using sapropel extract concentrations of 1.0%, 2.0%, and 2.5%. The highest biomass productivity was obtained at a 2.5% concentration, where fresh green mass reached 44.8 kg per tray (25.45 kg m−2), representing a 1.6-fold increase compared with the control treatment, which consisted of identical hydroponic cultivation conditions without sapropel extract addition. The recirculating irrigation system reduced specific water consumption, while optimized LED lighting improved energy-use efficiency. The results demonstrate that integration of natural bioactive supplementation with automated environmental control can significantly enhance hydroponic forage productivity while reducing specific resource inputs.