Submitted to: USDA Symposium on Natural Resource Management to Offset Greenhouse Gas Emissions
Publication Type: Abstract only
Publication Acceptance Date: 11/20/2002
Publication Date: 11/20/2002
Citation: Franzluebbers, A.J., Stuedemann, J.A. 2002. Soil-profile organic carbon and total nitrogen under bermudagrass management in the southern piedmont usa. USDA Symposium on Natural Resource Management to Offset Greenhouse Gas Emissions. Interpretive Summary:
Technical Abstract: Estimates of potential carbon (C) and nitrogen (N) sequestration at depths below the traditional plow layer (0-30 cm) are limited, but are needed to improve our understanding of management influences on greenhouse gas emissions and nutrient cycling. Soil samples were collected under `Coastal' bermudagrass in 1994 and 1999 at depths to 1.5 m. Forage utilization by grazing cattle led to greater soil organic C and total N sequestration rates than by haying. Fertilization regime had little impact on changes in soil organic C and total N. Soil organic C and total N accumulated significantly within the surface 30 cm of soil, but sequestration estimates for soil below 30 cm were below the levels of experimental variability. These results suggest that management-induced changes in soil organic C and total N can be reliably estimated within the surface 30 cm where inputs are greatest, but that estimates of C and N sequestration below 30 cm require highly controlled conditions to account for natural variability in soil and/or a time period greater than five years to allow for sufficiently large changes to occur.