Delineating Field Scale Functional Soil Mapping Units

Abstract

Current soil mapping units contain qualitative parameters, which makes it difficult to integrate them with other agronomic models or decision making support systems. In this work, we propose a fresh look at soil mapping and its functionality so that it can be spatially integrated with the current field and watershed scale and water resources models. This enhancement to the soil mapping practice could be made possible by scaling up the physically-based parameters of the pedostructure or the soil-water medium characterization to the field scale following the System’s Theory Approach. The hypothesis of this research is based on the pedostructure concept, which is an approach of the hierarchical functional entities including primary particles, primary peds, soil horizon, and soil mapping units (Braudeau et al., 2004). The hypothesis behind this research is that the pedostructural parameters are independent organizational parameters that fully characterize the soil medium as determined using the continuously measured shrinkage curve and they can be exclusively used as a basis to generate functional soil mapping units. These functional units represent soil units that reflect homogenous pedostructural parameters. We will generate these functional mapping units for Haggerty-Cox property, West Lafayette, Indiana using topographic maps, existing soil survey database (SSURGO), and pedostructural parameters (PS) following the System’s Theory approach. The System’s Theory approach is a technique used to define the common area among different data layers by overlaying the layers that represent the area under study systematically starting from the largest layer and ending at the smallest entity. The resulting soil mapping unit will assist in the decision support system data analysis, which in turn will enhance and allow for the prediction of water and chemical transport and interactions.