Submitted to: Soil Ecology Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 5/20/2001
Publication Date: 5/20/2001
Citation: Franzluebbers, A.J., Stuedemann, J.A. 2001. Particulate and biologically active soil carbon pools under grazed and ungrazed bermudagrass in the Southern Piedmont USA. Soil Ecology Meeting Abstracts.
Technical Abstract: The effect of forage management strategies on carbon cycling is of importance to the understanding of greenhouse gas emissions, agronomic productivity, and changes in soil quality. Particulate organic C (POC), soil microbial biomass C (SMBC), and potential C mineralization (CMIN) were evaluated during 4 years in response to N fertilization [inorganic only, crimson clover (Trifolium incarnatum L.) cover crop plus inorganic, and broiler litter] and forage harvest strategy (unharvested, low and high grazing pressure, and hayed). Accumulation of POC, SMBC, and CMIN with time was greatest at a depth of 0 to 2 cm and not different among fertilization strategies. To a depth of 6 cm, POC accumulated at a rate of 65 to 73 g/m2/yr under unharvested or hayed strategies and at a rate of 136 to 144 g/m2/yr under cattle grazing strategies. Accumulation rate of SMBC was also dependent upon forage utilization intensity, averaging 5.1, 9.6, 11.9, and 7.4 g/m2/yr under unharvested, low grazing pressure, high grazing pressure, and hayed strategies, respectively. Particulate and biologically active soil C pools improved under all forage management strategies, although with cattle grazing the rate of improvement nearly doubled compared with an unharvested strategy.