Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: November 9, 2000
Publication Date: N/A
Technical Abstract: Soil sampling by zones as opposed to grid sampling is appealing to producers if accuracy is achieved and costs are reduced. The objective of this research was to evaluate and compare various methods for delineating within-field zones for soil sampling and nutrient management. Ground- and aerial-based information sources were collected and analyzed to evaluate spatial structure and dissimilarity within fields. Unsupervised continuou classification of soil electrical conductivity, elevation, and slope data resulted in zones that corresponded well to soil fertility in fields with little manuring or buildup fertilization. Processed aerial images of bare soil also provided classification that followed field variation due to hydrology. Both of these methods have the advantage of relying on numeric and georeferenced field measurements. Detailed soil survey using traditional soil mapping techniques defined zones comparable to automated methods, but was generally more labor intensive. Management by zones requires confidence that the sub-field delineation criteria correspond with the management intended for the zones.