Development and application of digital soil mapping within traditional soil survey: What will it grow into?

Abstract

In this Chapter we describe our use of digital soil mapping estimates as input to traditional field soil survey in California, U.S.A. We also describe the development of these raster soil property models as stand-alone products, and practical implications of their use. This Chapter deals with application of existing digital soil mapping tools in active soil surveys, rather than research of new methods. The soil survey program in the United States is nearing completion of once-over coverage of the nation. Many potential soil survey users in the remaining unmapped areas expect to use traditional polygon-based soil maps. Soil-landscape models based on field point data have been developed in support of selected soil survey projects. We expand on our previous models in a test area that has existing point data and polygon soil mapping. New soil-forming factor covariates (IFSAR elevation data and ASTER satellite images) are used to derive the models. Minor improvements in the model estimates were obtained. Then significant variables from these models are used to test the feasibility of the creation of field soil survey office tools. We feel that raster soil-landscape models are a developmental product of soil survey. They are just becoming useful as pre-mapping estimates of the spatial distribution of some individual soil properties. The explicit estimation of all significant soil properties based on a suite of individual models is still to be developed. This is required before informed land management decisions can be based on digital soil mapping. Since natural resource management methods and regulations are coordinated locally, regionally, and nationally, standards for the creation and implementation of these models are required for consistent and coordinated outputs within a nation. © 2008 Springer Science+Business Media B.V.