Calibration and Validation of a Soil‐Landscape Model for Predicting Soil Drainage Class

Autor: Bell, James C., Cunningham, Robert L., Havens, Matthew W.
Zdroj: Soil Science Society of America Journal; November 1992, Vol. 56 Issue: 6 p1860-1866, 7p
Abstrakt: The soil‐landscape relationships frequently used for soil mapping activities are seldom documented. We developed a statistical model that relates soil drainage classes to eight landscape parameters describing slope morphology, proximity to surface drainage features, and soil parent material. Soil profiles and landscape parameters were described at 305 randomly selected sampling points within the Mifflintown 7.5‐min topographic quadrangle in the unglaciated ridge and valley physiographic province of central Pennsylvania. Variables defining the spatial structure of the landscape were derived from digitized 1:24 000 scale maps of streams and drainageways, surficial geology, bedrock geology, and a digital elevation model. These data were stored in a geographic information system and overlaid with the sampling point locations to define a database of 305 known soil‐landscape combinations. These soil‐landscape combinations were used to derive a statistical soil‐landscape model using multivariate discriminant analysis and class frequency information. For soil drainage class, a 74% overall agreement with field observations was found for the model using a cross‐validation approach, compared with 69% for the published soil survey. The model correctly predicted a majority of the observations within each drainage class and provided a consistent method of extrapolating point information about soils to the three‐dimensional landscape.
Databáze: Supplemental Index