Influência dos parâmetros de campo no desempenho dos sistemas de irrigação por sulcos.

Abstract

This research developed an analysis on the furrow irrigation system, purposing to verity the influence of the field parameters on the performance of these systems. The study was performed basing on data from field evaluations done by the author in the Sao Goncalo irrigation district, and data published by Walker e Humpherys (1983). The influence of the field parameters on the performance of these systems was verified through a sensitivity analysis, using the SIRTOM (Azevedc-,1992) and SIRMOD (Utah State University, 1989) computer mathematical models. For the field conditions in question, the results showed that the soil infiltration and furrow length are the parameters that most affect the system performance. Thus, it is obvious the importance of to establish relationships between inflow and furrow length that would provide adequate values for these parameters, for site specific conditions. The segregate effects of roughness, slope and furrow cross section were relatively small. However, the effects of roughness and slope were better visualized when associated with the furrow length effect. The deep percolation rate is much more affected by the parameters than the runoff rate. This shows the importance of performing a seasonal monitoring of the advance phase, since this phase gives the most contribution to the deep percolation losses.