Resource efficiency is essential in today's approach to horticulture. The global problems of water scarcity, soil pollution, biodiversity loss, and rapid growth of the global population require increased food production with fewer resources.
Resource efficiency is an indicator that allows defining how much biomass an agri-food system can produce per unit of the resource used. Closed hydroponic systems, such as vertical hydroponic towers (VHTs), exhibit high resource efficiency. In these systems, the water use efficiency (WUE) and the nutrient use efficiency (NUE) can be calculated in terms of the water loss through transpiration and the ion concentration in the nutrient solution. The research aimed to determine the WUE and NUE for chard crops in VHT under greenhouse conditions and to evaluate its feasibility as an urban and peri-urban system for leafy vegetable production. Trials were carried out with chard in the fall 2024 in a tunnel-type greenhouse at the facilities of the Autonomous University of San Luis Potosi. The VHTs were built with a 20 L square lower deposit on which a cylindrical pipeline of 11.5 cm in diameter and 1.6 m in height was vertically placed. Each pipe had 45 growing containers distributed on 15 levels of three containers spaced vertically 9 cm and a density of 25 plants·m−2. The experimental design was completely randomized with three treatments (75, 100, and 125% of Steiner's nutrient solution) and three replications. The transpiration (Tr) of the crop (recording weight loss in the deposit) and the shoot fresh weight (SFW) of the plants were measured daily using a scale. An ANOVA and Tukey's test for mean differentiation were performed with p < 0.05. Significant differences were found between treatments for SFW, WUE and NUE obtaining the best results at 75% of Steiner's nutrient solution. Results show that WUE increased between 3 and 6 times, and NUE between 3 and 12 times compared to chard grown in soil. These results were equal and even higher than horizontal hydroponic systems or vertical farms.
Vertical hydroponic closed towers installed in greenhouses are an optimal horticultural production system with high resources use efficiency. The implementation of VHT is feasible in areas where there is water scarcity or have a high population density.
López-Mora, M.F.; Borgovan, C.; González-Murillo, C.A.; Solano-Betancour, M.; Quintero-Castellanos, M.F.; Guzmán, M. Resource Efficiency of Swiss Chard Crop in Vertical Hydroponic Towers Under Greenhouse Conditions. Biol. Life Sci. Forum 2025, 47, 5. https://doi.org/10.3390/blsf2025047005
Source: MDPI
