The pedostructure concept is an improved method of predicting the behavior of the soil-water media by characterizing a soil based upon physically-based soil structural properties. By physically defining the relationships between soil aggregates, the primary peds, and the macropore and micropore systems within the soil matrix, the pedostructure model is better able to define the thermodynamic properties of the hierarchical soil structure. There are 15 unique parameters that describe the pedostructure, extracted from the continuously measured soil shrinkage, swelling, potential, and conductivity curves. These procedures take specialized laboratory equipment and training; therefore, estimation methods of these parameters from common soil physical properties are needed to further expand the use of the pedostructure concept. In this work, we developed regression equations for five soil series in Indiana that had their pedostructure parameters and soil physical properties measured in the laboratory. Additionally, regression equations were developed for the estimated soil physical properties available from online soil databases. The pedostructure parameters, Vo (the specific volume of the soil after oven drying), Wl (the water content of the soil at saturation, and Km (the equilibrium constant between macropore and micropore drying) can be estimated from measured common soil physical properties with a high degree of accuracy, while Ema (the potential energy at the surface of the primary peds) cannot be estimated accurately with the soil physical properties measured in this work. Using estimated soil physical properties introduced substantial error for Km, sigma, and Kbs, while not adding additional error to the other parameters. Organic matter is influential in predicting 6 of the 7 parameters, while soil water contents do not improve the prediction ability for any of the parameters.;Additionally, a cursory investigation into how these parameters evolve with changing land management was administered. The pedostructure parameters were obtained from soil samples under two different tillage treatments (zero-tillage and rotational tillage). The zero-tillage treatment significantly increased the value of Wm and Vo, while decreasing the value of Kbs compared to rotational tillage. This indicates that zero-tillage is capable of storing more water in the micropore system for use by plants and promoting root growth by having a lower bulk density in dry conditions. No other parameters were significantly different between the two tillage systems. It is hoped that this work will spur more investigations into how the pedostructure concept accounts for the evolution of soil properties and promote the usage of the pedostructure model as a land use decision-making tool.
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