Monday, November 5, 2007
103-7

Mapping Soil pH Buffering Capacity for Crop Production Fields with Remote Sesing.

Feng Chen1, David Kissel2, and A. Wayne1. (1) University of Georgia, Dept. of Crop & Soil Sciences, University Of Georgia, Athens, GA 30602, (2) 2400 College Station Rd., University of Georgia, University of Georgia, Ag & Environmental Services Laboratories, Athens, GA 30602-9105

Soil pH buffering capacity, varying spatially within crop production fields, could be used to define sampling zones for assessing lime requirement and to model the changes in soil pH when acid forming fertilizers or manures are added to a field. Studies have shown that soil pH buffering capacity could be predicted from surface soil organic carbon (SOC) and soil clay contents. Studies have also shown that the spatial distribution of SOC and clay could further be predicted with remote sensing. These studies would lead us to raise the issue of possibly mapping soil pH buffering capacity with remote sensing. Our objective in this study was to find a way to map soil pH buffering capacity using remote sensing. Representative samples of surface soils over various fields were titrated to determine the buffer slope of pH vs. base added, and then the relationship between soil pH buffer slope and remotely sensed image data was examined with multiple regression analysis. The regression equation that best fit the data was applied in geographic information system (GIS) software to develop maps of the soil pH buffer capacity for the fields in the Coastal plain of Georgia.