Variability and spatial distribution of hydrodynamic properties in soil with preserved Caatinga

ABSTRACT The functions of soil water retention and hydraulic conductivity are indispensable for the characterization and modeling of the infiltration and water transfer processes in the vadose zone. In the case of the Brazilian semi-arid region, characterized by the scarcity of water resources, there is a lack of information on the hydrodynamic properties of the soil. Also, these properties have numerous factors of variability, requiring the characterization of their magnitude and distribution in space. This research presents an analysis of the infiltration process and the hydrodynamic properties of the soil under native Caatinga forest, observing its spatial distribution. This vegetation is typical of the Brazilian semi-arid region. One developed a 48-point grid in an area of approximately 875 m2, and applied on it the Beerkan methodology. The analyzes were performed based on the application of the BEST-Slope algorithm and statistical measures of the position, dispersion, and adherence tests. The results showed medium to high variability indices for the hydrodynamic properties, with random spatial distribution, despite the verification of a homogeneous texture in the area. Thus, it was found that the soil structure was predominant in the processes of water infiltration.