Evaluación de un sistema de reutilización dual biofiltro-huerto para biorremediación de agua empleando sustratos intercambiables como alternativa viable para cultivar especies hortícolas

Abstract

Water scarcity and pollution pose serious challenges to agriculture, mainly due to the excessive use of fertilizers and pesticides. In Cuenca, Ecuador, monitoring by ETAPA has confirmed the presence of such contaminants, highlighting the need for sustainable remediation solutions. This study evaluated a dual-use biofilter-garden system for the treatment of wastewater and its viability in horticultural production. Three treatments were tested: T0 (commercial substrate), T1 and T2 (mixtures of gravel, sand, clay, rice husk, coconut fiber, pumice, peat, and charcoal), in a completely randomized design with three replications, using simulated wastewater. Water quality parameters (pH, EC, COD, total nitrogen, total phosphorus, potassium) and substrate parameters (OM, C/N, NO₃, P₂O₅, K₂O) were monitored for 20 days, while lettuce growth was assessed over 42 days. T2 showed the highest pollutant removal efficiency, reducing total nitrogen (1 mg/L), total phosphorus (6.83 mg/L), and COD (230 mg/L), approaching the limits set by TULSMA. T2 also retained more nitrates (22.34 ppm), while T1 released more phosphorus (0.74 ppm). Regarding plant growth, T0 achieved the highest height (8.4 cm) and fresh weight (6.19 g), with 100% survival in T0 and T1. The results indicate that the dual biofilter-garden system is a viable option for sustainable water remediation and horticultural production. T2 stood out for its water treatment capacity, although further improvements in substrate nutrition and simultaneous cultivation during bioremediation are recommended to enhance productivity.