Submitted to: American Society of Agronomy Meetings
Publication Type: Abstract Only
Publication Acceptance Date: 7/28/2004
Publication Date: 10/31/2004
Citation: Causarano, H.J., Shaw, J.N., Franzluebbers, A.J., Reeves, D.W., Raper, R.L. 2004. Relating soil organic carbon distribution to landscape variability in a piedmont pasture [abstract]. American Society of Agronomy-Crop Science Society of America-Soil Science Society of America Annual Meetings. 31 October - 4 November 2004, Seattle, Washington. CDROM.
Technical Abstract: Delineating zones within pasturelands that contain unique soil organic carbon (SOC) conditions would lead to a better understanding of how landscape characteristics affect SOC sequestration. We determined the relationship between SOC, terrain attributes and electrical conductivity in a Southern Piedmont pasture. Geo-referenced soil properties (SOC, texture, water content), electrical conductivity and terrain attributes were collected on a 6-ha grazed bermudagrass [Cynodon dactylon (L.) Pers.] pasture near Watkinsville, GA (Typic Kanhapludults). Near infrared, red and green reflectance values were obtained from an aerial photograph. Soil properties, terrain attributes and remote sensing explained 46% of SOC variability. Factor analysis followed by unsupervised classification of the factor scores identified five clusters in the field. SOC was statistically different (P[ 0.01) between clusters. Soil organic C variation among clusters was explained mainly by elevation, slope, plan curvature, and Compound Topographic Index. Cluster delineation based on factor analysis of terrain attributes, soilelectrical conductivity and remote sensing provided a useful approach for evaluating SOC-topography relationships.