Furrow irrigation with and without use of runnoff water

Abstract

Two furrow irrigation systems were compared, the first one consisting of application of a constant outflow through siphons, for R values equal to 0.26, 1 and 2. The second system consisted of use of runoff water for R values equal to 0.50, 1 and 2. When R value increased, in both the irrigation systems the losses by percolation decreased while the efficiencies of application and distribution increased, as well as the runoff losses. The irrigation efficiency increased with R value when the runoff water was used, occurring, however, the opposite when this water was not used. Complementary observations were made concerning to measurements of the fluctuation of the outlet disponible runoff during the irrigation of five consecutive sectors aiming at the dimension of irrigation systems with use of runoff water.