Pedotransfer Functions to Estimate Parameters for Soil Phosphorus Models

Abstract

Core Ideas Equations with relatively simple parameters were provided to estimate soil solution phosphorus. A regression was fitted to estimate partition coefficients of desorption isotherms. The functions presented facilitate parameterization of existing P simulation models. Parameters of mechanistic and empirical models to simulate nutrient dynamics in soil–plant systems are not always readily available. One way to address this problem is by developing pedotransfer functions to estimate such parameters. In this study, we derive pedotransfer functions to estimate the P contents in soil solutions (Psol) of Brazilian soils and to estimate the partition coefficient of P desorption isotherms (kd,ds). We compiled data from previous studies and developed linear and nonlinear regression models to estimate P in soil solution as a function of P extracted by Mehlich‐1 (M1) and of soil clay. A regression model was also used to obtain a relationship between the partition coefficients of sorption and desorption isotherms for soils with different physicochemical characteristics. The functions presented here facilitate parameterization of existing P simulation models for Brazilian soils that are increasingly important for both scientific research and nutrient management.