Report on soil information systems of the USDA natural resources conservation service

The development and applications of the national soil information system (NASIS) for the United States Department of Agriculture are described in this report by examining the overall characteristics of the USDA system and related information on soil survey maps and associated databases, soil interpretations, and natural resource applications. The National Cooperative Soil Survey and its various regional, state and local affiliates provide direction, leadership, and scientific collaborative research and applications to increase the usefulness of soil survey information for society’s needs. Soil mapping ranges in scale from detailed county levels to major land resource areas or states with digital products such as SSURGO and STATSGO published for public distribution and direct use on the Internet. Transferring soil survey information to a wide spectrum of users is accomplished using benchmark soils and soil survey interpretations from rule-based methods within the National Soil Survey Information System (NASIS). Soil survey interpretations consider large scale variability in soil properties and land use and management parameters to refine the interpretations for local conditions. An overview of NASIS soil properties and qualities also describes the statistical summary of soil properties and thematic maps created from map unit data. Selected examples of GIS-based applications reveal the basic functions and primary components of the SIS. Soil classification focuses on an example of soil correlation with USDA Soil Taxonomy and the World Reference Base for Soil Resources. Technical references and applications of SIS for soil use and management interpretations provide natural resources information at multiple scales ranging from farm to watershed and larger areas such as nations, ecological regions or continents.