Relação dos índices hidráulico-energéticos com a condutividade hidráulica do solo saturado

Abstract

The saturated soil hydraulic conductivity ( K s ) is an important physical property that can be used to characterize, figure out and simulate soil hydrological processes. The analysis of the soil physical quality (SPQ) is usually based on its properties related t o mass and energy transfer that occur in this porous medium . The soil water retention curve (SWRC) is a widely used hydraulic function that is related to SPQ. Thus, SPQ indicators can be derived from SWRC, such as the pore size distribution, relative field capacity, plant available water, drainable porosity and soil hydraulic energy indices. In this work, 395 measured SWRC's, available in the UNSODA 2.0 database (76%) and scientific articles (5%) and others provided by research collaborators (19%) were fi tted to the van Genuchten (1980) with Mualem’s restriction (1976) V G M ) equation. With the results of the vG parameters, the hydraulic energ y indices were obtained in order to verify whether they are correlated with K s . The found parametric and non parametric correlation results were split up according to the textural classes of the soils examined . The significant influence of K s on at least one of the absolute hydraulic energetic indexes ( A a and WR a ) was verified on the numerical scale when all textures were grouped and on both scales , numerical and logarithmic ( pF ) for clay ey and silt y textures. Ks showed significant impact on two absolute hydraulic-energy indices in four textural groups. Furthermore, K s had influence on the sum o f the absolute indices in pF scale for 5 of the 6 textural groups , with a significant linear correlation in the clayey texture when the log arithm was applied in the sum of the absolute indices. The significant K s influence was also observed on the ratios WR a /AD and A a ϕ D in 4 of the 6 groups , and the use of the se indices are recommended for the development of pedotransfer equations PTFs for the K s prediction