Relating Soil Organic Carbon Distribution to landscape variability in a Piedmont Pasture. (4331)
Authors:
H.J. Causarano* - Auburn University, AL, and FCA-UNA, Paraguay J.N. Shaw - Auburn University, AL
A.J. Franzluebbers - USDA-ARS, Watkinsville, GA D.W. Reeves - USDA-ARS, Watkinsville, GA R.L. Raper - USDA-ARS, Auburn, AL
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, soil electrical conductivity and remote sensing provided a useful approach for evaluating SOC-topography relationships.
Speaker Information: Hector Causarano, Auburn University, AL, and FCA-UNA, Paraguay,
USDA-ARS-NSDL411 S. Donahue Drive, Auburn, AL 36832; Phone: (334) 844-4741 ext. 170; E-mail:
Session Information: Monday, November 1, 2004, 4:00 PM-6:00 PM Presentation Start: 4:00 PM (Poster Board Number: 2548)
