Aeroponic and NFT system optimization for lettuce: effects of flow rate and nutrient source on water use efficiency, growth, and profitability

Abstract

Hydroponic cultivation is an innovative method for cultivating plants that does not rely on traditional soil. The present research aimed to enhance water use efficiency using different hydroponic systems of NFT(nutrient film technique system)and aeroponics with the use of water sources (well water + nutrient solution and fish culture) and water flow rates of 0.8, 1.2, 1.6, and 2 l/h. System performance was evaluated in terms of nutrient uptake, water and nutrient index (amount of water consumption and nutrient solution consumption), crop characteristics, water use efficiency, and cost estimation. A split–split plot design with three replicates is used, and the data are statistically analyzed using SPSS. Results indicate that the optimum water flow rates are 1.6 and 0.8 l/h using NFT and aeroponic systems, respectively. The aeroponic system enhanced water use efficiency by 64.65 and 64.34% compared with the NFT system under nutrient solution and fish culture, respectively. The net profit using aeroponic was 34.38% and 5.37% higher than the NFT system using nutrient solution and fish farming, respectively. Using fish farming as a sustainable source of nitrogen, along with other nutrients, has provided ideal absorption of nutrients for the plant in addition to achieving a high economic return compared to using nutrient solutions.