1. Atmosphere Above-ground biomass (gm -2 ) annually burned 3.0 ± 2.1 control 36.4 ± 27.3 Necromass (gm -2 ) *** annually burned 242.9 ± 79.4 control 2414.1 ± 177.9 Soil organic matter [LOI %] annually burned 2.31 ±.78 control 1.98 ±.79 Plant diversity Forb fract. annually burned 0.553 ± 0.442 control 0.383 ± 0.380 Shoot density Log(Density) annually burned 5.396 ± 1.171 control 5.518 ± 1.591 Fire-frequency effects on carbon dynamics in tallgrass prairie Bio 252-01 - 2003 Above-ground RGR annually burned ???? control ???? Below-ground biomass Below-ground RGR Above-ground respiration Soil respiration annually burned control Soil waterwk1*wk2* annually burned51.4 ±2.146.7 ±1.0 control46.0 ±1.652.3 ±1.5 Soil temperaturewk1*wk2* annually burned13.8±0.212.5 ±0.2 control10.5 ±0.311.0 ±0.1

3. Atmosphere Above-ground biomass (g/ m 2 ) *** annually burned 4.6 ± 1.4 control 20.5 ± 3.4 Necromass (g/m 2 ) *** annually burned 73.6 ± 24 control 624 ± 83.2 Soil organic matter [LOI %] annually burned control Plant diversity Forb fract. annually burned0.23 ±.06 control0.44 ±.13 Shoot density stems/ m 2 annually burned133 ± 21 control124 ± 21 Fire-frequency effects on carbon dynamics in tallgrass prairie Bio 252(Brown) - 2008 Above-ground RGR annually burned ???? control ???? Below-ground biomass (g/m 2 ) annually burned 490 ± 165 control 497 ± 115 Below-ground RGR Above-ground respiration Soil respiration (g/m 2 /hr) annually burned 1.3 ± 0.6 control 1.7 ± 0.9 Soil water*** annually burned27.4 ±0.7 control30.7 ±0.5 Soil temperature*** annually burned14.3±0.2 control10.7 ±0.2

4. Grass Biomass Fig 3: Grass biomass is significantly higher in burned than unburned prairie plots. (p=.006) Bars are one standard deviation from the mean. Bowman, O’Brien and Vaughan 2007

5. Forbs Fig. 1: Forbs biomass is not significantly different between burned and unburned plots. (p=0.853) Bars are one standard error from the mean. Bowman, O’Brien and Vaughan 2007

6. Necromass Fig 2: The mean of necromass in unburned plots is slightly higher than in burned plots, however the results are non-significant (p=0.412) Bars are one standard deviation from the mean. Bowman, O’Brien and Vaughan 2007

7. Results Big Bluestem is strongly affected by recent burning, while Indian Grass is not. Bars are one standard error from the mean. Davenport and Cohn 2007