HR: 0800h
AN: B41A-0155    [Abstracts]
TI: Comparative Effects of Burning on Ecosystem Fluxes and Productivity in Two Adjacent Tall Grass Prairie Pastures
AU: * Billesbach, D P
EM: dbillesbach1@unl.edu
AF: University of Nebraska-Lincoln, 25 L.W. Chase Hall, Lincoln, NE 68583-0726 United States
AU: Torn, M S
EM: mstorn@lbl.gov
AF: Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, CA 94720 United States
AU: Fischer, M L
EM: mlfischer@lbl.gov
AF: Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, CA 94720 United States
AU: Mayeux, H
EM: hmayeux@grl1.grl.ars.usda.gov
AF: USDA ARS Grazinglands Research Laboratory, 7207 W. Cheyenne St., El Reno, OK 73036 United States
AU: Doyle, G
EM: gdoyle@grl1.grl.ars.usda.gov
AF: USDA ARS Grazinglands Research Laboratory, 7207 W. Cheyenne St., El Reno, OK 73036 United States
AU: Dowell, P
EM: pdowell@ops.sgp.arm.gov
AF: ARCF Southern Great Plains Site Office, 309600 EW 28, Billings, OK 74630 United States
AB: Management practices can have large effects on ecosystem productivity. In grasslands and prairies, one of the most common management tools is fire. While judicious burning generally increases grassland productivity, there have been few controlled studies that quantify the effect of fire on the fluxes of carbon, water, and energy. We have initiated an experiment in two adjacent pastures with similar native prairie vegetation, grazing, and burning histories located in the USDA, Agricultural Research Service's Grazinglands Research Laboratory in central Oklahoma. In March, 2005, we burned one pasture while leaving the other intact as a control. Identical eddy covariance and automated soil respiration systems and sampling protocols were installed and are being used in each pasture. Measurements include: net ecosystem exchange (NEE), soil carbon dioxide flux, soil moisture and temperature, and plant biomass by C3 and C4 functional group. Early in the growing season, there was more above ground green biomass in the unburned, control pasture. This was accompanied by higher NEE and latent heat fluxes. Later in the season, however, significantly greater productivity was observed (biomass and NEE) in the burned pasture compared to the unburned control.
DE: 0402 Agricultural systems
DE: 0428 Carbon cycling (4806)
DE: 1632 Land cover change
SC: Biogeosciences [B]
MN: Fall Meeting 2005