Estimação da percolação em lisímetros de drenagem e evapotranspiração da bananeira usando TDR

Abstract

The generation and analysis of methods that allow quantifying the percolation, root water uptake and crop evapotranspiration provides an understanding of the processes involved in the soil-water-plant-atmosphere relationship. Some basic components of soil-water-plant-atmosphere system can be determined by soil water balance using TDR. The specific aims of this study were: (i) analyze the estimation of soil water percolation with TDR using Darcy’s law determining K(θ) functions by direct field methods and indirect laboratory methods, as well as by monitoring of water storage variation in soil profile monitored by different numbers of TDR probe; (ii) set a minimum number of monitoring for installation of TDR probes that allows obtaining a soil water balance under field conditions with precision and accuracy compared to use drainage lysimeters; (iii) determine the evapotranspiration, water uptake patterns of banana crop and indicate the correct placement of sensors. Were built eight drainage lysimeters with 5m3 and filled with sandy loam soil and sandy clay soil. To test the consistency of TDR-estimated percolation levels in comparison with the observed leachate levels in the drainage lysimeters, the combined null hypothesis was tested with a confidence level of 95%. The main scientific contributions of this work relate to the production of a methodology that enables the determination of percolation and banana evapotranspiration through soil water balance using TDR with precision and accuracy near the lysimeter method.