Development of pedotransfer functions for Brazilian soils

Pedotransfer Functions (PFT’s) have several applications in the agri-environmental field, hydrodynamically characterizing soils in a less costly and more accessible way. The work proposed to develop equations that characterized Brazilian tropical soils through numerical validations available in the HYBRAS database, comparing them with others available in the literature. To analyze the performance of the proposed methods, we investigated the classical hydrodynamic parameters. The nonlinear equations obtained the best modeling, followed by the linear model and two others. When compared to the literature, the PTFs developed in this study proved to be more effective in estimating all the hydrodynamic parameters evaluated, especially those developed from multiple nonlinear regressions. However, its use in the Plinthossols, Luvisols, and Vertisols classes is not recommended since they do not belong to the database. It is also not recommended to use PTF to estimate: i) the saturated volumetric humidity in silty soils; ii) the residual volumetric humidity for soils of the textural classes Clay and Loam; iii) the parameter α in silty clay Loam, clay Loam, and silty Loam soils; and iv) the parameter n of Loam class soils.