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Table 4 Linear mixed effects model predicting change in relative growth rates (RGR) from pre-fire heights to one-year post-fire heights (n = 287) following 13 prescribed fires, from 2006 to 2010, at Archbold Biological Station, Venus, Florida, USA, where the effect of prescribed fire on resprouting Florida vegetation was examined. Plants within transects were not independent so transect was evaluated as a random effect (variance = 0.011) in the model. Variables included maximum fire temperature, residence time in seconds (log), burn season, habitat, species group, and two-way interactions. Reference categories for burn season were “Fire”, “Scrubby Flatwoods” for habitat, and “Oaks” for species groups. The burn season * habitat interaction was not included due to low or missing cells. For each variable, the estimated coefficient (β ± standard error [SE]) shows the relationship and magnitude of change with relative growth. Sample size (n) is provided for each group and the mean first-year relative growth rate (RGR). Significant effects (P < 0.05) are highlighted in bold and marginal predictors are in italics (P < 0.1). The random effects of transect were also not significant (P < 0.001)

From: Are fire temperatures and residence times good predictors of survival and regrowth for resprouters in Florida, USA, scrub?

Fixed effects β (SE) P-value R2 n First year RGR
Intercept −0.70 (0.370) 0.062 0.254   −0.410
Maximum temperature <0.01 (<0.001) 0.107 0.009 287  
Residence time (log) 0.11 (0.128) 0.401 0.003 287  
Burn season Fire     148 −0.457
Wet 0.32 (0.211) 0.146 0.010 78 −0.291
Dry 0.14 (0.241) 0.557 0.002 61 −0.516
Habitat Scrubby flatwoods     130 −0.372
Sandhill −0.15 (0.209) 0.486 0.002 68 −0.527
Sand pine–oak scrub −0.43 (0.244) 0.105 0.014 30 −0.384
Flatwoods −0.37 (0.244) 0.130 0.009 59 −0.441
Species groups Oaks     90 −0.535
Palms 0.43 (0.291) 0.140 0.007 47 −0.113
Ericads 0.25 (0.245) 0.316 0.004 61 −0.654
Graminoids 0.46 (0.625) 0.463 0.002 27 0.250
Shrubs −0.25 (0.305) 0.415 0.002 62 −0.567
Sandhill*Palms 0.21 (0.310) 0.509 0.001   
Sand pine–oak scrub*Palms 0.50 (0.397) 0.205 0.005   
Flatwoods*Palms 0.33 (0.353) 0.370 0.003   
Sandhill*Ericads −0.17 (0.328) 0.596 0.001   
Sand pine–oak scrub*Ericads 0.81 (0.498) 0.103 0.009   
Flatwoods*Ericads 0.42 (0.302) 0.166 0.007   
Sandhill*Graminoids −0.78 (0.502) 0.122 0.008   
Sand pine–oak scrub*Graminoids −0.16 (0.526) 0.760 <0.001   
Flatwoods*Graminoids −0.34 (0.445) 0.445 0.002   
Sandhill*Shrubs 0.06 (0.293) 0.839 <0.001   
Sand pine–oak scrub*Shrubs 0.27 (0.427) 0.524 0.001   
Flatwoods*Shrubs 0.41 (0.297) 0.166 0.007   
Wet*Palms −0.33 (0.309) 0.284 0.004   
Dry*Palms −0.03 (0.340) 0.952 <0.001   
Wet*Ericads −0.84 (0.292) 0.004 0.029   
Dry*Ericads −0.29 (0.314) 0.355 0.003   
Wet*Graminoids 0.72 (0.752) 0.342 0.003   
Dry*Graminoids 0.97 (0.708) 0.173 0.006   
Wet*Shrubs −0.01 (0.303) 0.965 <0.001   
Dry*Shrubs 0.35 (0.376) 0.357 0.003