Bryan D. Mayhan1, D. Brenton Myers2, R. J. Miles2, and Jennifer L. Goyne1. (1) Center for Agricultural, Resource and Env Systems, 130 Mumford Hall, Univ of Missouri, Columbia, MO 65211, (2) Univ of Missouri, 269 Ag Engineering Bldg, Columbia, MO 65211
The Cooperative soil survey program in Missouri has completed its first generation survey after fifty years of field work, cartography, and more recently, GIS database production. The second generation of the Missouri soil survey is a comprehensive effort to address data quality issues. First, soil series were established as the survey program advanced. This caused many mismatches of delineations and nomenclature at county boundaries. Second, delineation problems and inconsistently developed series concepts caused excessive statistical variation in the composition of many map units. Digital elevation models (DEM) are used to identify and solve some of these problems because of landform control on soil genesis and map-unit distribution. Statistical distribution of DEM derivatives within map units, and spatial parameters of map unit polygons are used to enhance error detection, redraw map-unit boundaries, and to update older county surveys with newer soil series concepts. The statistical distributions of first and second derivatives of DEMs were summarized by soil series and by mapunit. Representative ranges of these DEM derivatives were calculated and identified for series, map unit and map unit inclusions. These quality control methods and analyses are critical tools in compiling and constructing a more reliable soil survey to help end users make better land use decisions.