Viabilidade econômica e sanitária do cultivo da alface em sistema hidropônico com diferentes tipos de água.

Abstract

Currently, one of the major concerns is the quality of surface water, which has been used as a support for the disposal of waste produced by man. The objective of this study was to evaluate the use of residual and salt water in the production of lettuce (Lactuca sativa L.) varieties in a hydroponic system at the CCT / UEPB of Lagoa Seca - PB, aiming to contribute to the viability of its application in regional family agriculture. The experiment was conducted in a hydroponic system using the laminar nutrient flow technique (NFT). The experimental design was randomized blocks with the treatments arranged in split plots subdivided in a 7x3 factorial scheme, with three replications, whose factors were 7 hydroponic solutions and three lettuce cultivars. Optimized nutrient solutions were formulated by reference to Furlani's nutrient solution. The experimental portion consisted of the nutritive solutions (S): S1 = solution of Furlani; S2 = domestic wastewater; S3 = optimized domestic wastewater; S4 = brackish water from tubular wells to collect groundwater; S5 = brackish tubular well water for optimal groundwater abstraction; S6 = wastewater solution from the UASB reactor and S7 = wastewater solution from the optimized UASB reactor). The results of this research evidenced the viability (economic, social and environmental) in the use of effluents and brackish water in hydroponic cultivation, providing vegetables with sanitary levels adequate to consumption. However, through government support for credit and technical assistance assistance in order to promote technical knowledge and environmental education that provide a correct agricultural management. The use of the solutions suggested in this research (S5, S6 and S7) reduces the negative impact on the environment by avoiding its introduction into water bodies, as well as saving on the use of fertilizers in agriculture and, consequently, increasing the economic viability of All treatments met the standard established by RDC No. 12 of January 2, 2001 of ANVISA, which were absent for thermotolerant coliforms and having tolerable levels of total coliforms.