Abstract
Producing leafy vegetables in intensive hydroponic systems requires knowledge of production cost variables and their proper management. Flow rate is a decisive factor in both production and operating costs as it directly affects energy consumption. This study aimed to assess the productive aspects of lettuce in relation to nutrient solution flow rate and energy consumption in a nutrient flow technique hydroponic system. The experiment was conducted on individual benches, with treatments consisting of five nutrient solution flow rates: 0.5; 1.0; 1.5; 2.0 and 2.5 liters per minute (L/min). Production components and water pump operating costs were assessed. Average plant production was 250.5, 282.75, 316, 338.5 and 346.6 g for flow rates of 0.5, 1.0, 1.5, 2.0 and 2.5 L/min, respectively. The lowest operational energy costs and the highest production performance was observed at a flow rate of 1.5 L/min, while, reduced performance was noted at flow rates of 0.5 and 1.0 L/min. The different water management strategies evaluated indicate the feasibility of operating in a hydroponic system, considering all cost-benefit (C/B) ratios > 1.
References
CASEY, L. et al. Comparative environmental footprints of lettuce supplied by hydroponic controlled-environment agriculture and field-based supply chains. Journal of Cleaner Production, v. 369, 2022. Available in: https://doi.org/10.1016/j.jclepro.2022.133214. Accessed in: Mar. 20, 2023.
DALASTRA, C.; TEIXEIRA FILHO, M. C. M.; VARGAS, P. F. Periodicity of exposure of hydroponic lettuce plants to nutrient solution. Revista Caatinga, v. 33, n. 1, p. 81–89, 2020. Available in: https://doi.org/10.1590/1983-21252020v33n109rc. Accessed in: May 04, 2023.
DJIDONOU, D.; LESKOVAR, D. Seasonal changes in growth, nitrogen nutrition, and yield of hydroponic lettuce. Hortscience, v. 54, 2019. Available in: https://doi.org/10.21273/HORTSCI13567-18. Accessed in: Mar. 04, 2023.
GOODMAN, W.; MINNER, J. Will the urban agricultural revolution be vertical and soilless? A case study of controlled environment agriculture in New York City. Land Use Policy, v. 83, p.160-173, 2019. Available in: https://doi.org/10.1016/j.landusepol.2018.12.038. Accessed in: Mar. 4, 2023.
GUMISIRIZA, M. et al. Building sustainable societies through vertical soilless farming: A cost-effectiveness analysis on a small-scale non-greenhouse hydroponic system. Sustainable Cities and Society, v. 83, 2022. Available in: https://doi.org/10.1016/j.scs.2022.103923. Accessed in: Mar. 20, 2023.
JUNIOR, C. H. et al.. Effect of electric conductivity, ionic concentration and flow of nutrient solutions in the production of hidroponic lettuce. Ciência e agrotecnologia, v. 32, n. 4, p. 1142–1147, 2008. Available in: https://doi.org/10.1590/S1413-70542008000400016. Accessed in: Mar. 1, 2023.
KANNAN, M. et al. Hydroponic farming – A state of art for the future agriculture. Materials Today: Proceedings, v. 68, p. 2163-2166, 2022. Available in: https://doi.org/10.1016/j.matpr.2022.08.416. Accessed in: Mar. 20, 2023.
LEI, C.; ENGESETH, N. J. Comparison of growth characteristics, functional qualities, and texture of hydroponically grown and soil-grown lettuce. LWT, v. 150, p. 111931, 2021. Available in: https://doi.org/10.1016/j.lwt.2021.111931. Accessed in: Mar.1, 2023.
MAJID, M. et al. Evaluation of hydroponic systems for the cultivation of Lettuce (Lactuca sativa L., var. Longifolia) and comparison with protected soil-based cultivation. Agricultural Water Management, v. 245, e106572, 2020. Available in: https://doi.org/10.1016/j.agwat.2020.106572. Accessed in: Apr. 12, 2023.
MARTIN, M.; MOLIN, E. Environmental assessment of an urban vertical hydroponic farming system in Sweden. Sustainability, v. 11, p.01-14, 2019. Available in: https://doi.org/10.3390/su11154124. Accessed in: Mar. 4, 2023.
REZENDE, R. et al. Diferentes soluções nutritivas aplicadas em duas vazões na produção hidropônica da cultura da alface. Irriga, v. 12, n. 3, p. 354-363, 2007.
SAUSEN, D. et al. Soilless cultivation: an alternative for marginal areas. Brazilian Journal of Development, v. 6, n. 3, p. 14888-14903, 2020. Available in: https://doi.org/10.34117/bjdv6n3-381. Accessed in: Apr. 12, 2023.
SOUZA, S. V.; GIMENES, R. M. T.; BINOTTO, E. Economic viability for deploying hydroponic system in emerging countries: A differentiated risk adjustment proposal. Land Use Policy, v. 83, 2019. Available in: https://doi.org/10.1016/j.landusepol.2019.02.020. Accessed in: Mar. 4, 2023.

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