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Table 2 Estimated coefficients (and corresponding standard errors) of general linear mixed-effects models of the abundance of Pinaceae and Fagaceae saplings and small trees (separate models for each combination) as a function of overstory composition (Overstory; oak, mixt, pine), total plot basal area (BA), climate variables (mean annual temperature and annual precipitation), occurrence of several disturbance types (wildfires, grazing, pests, wood extractions), land tenure (private, public or social), and the interactions between family and all the other variables

From: Regeneration patterns in Mexican pine-oak forests

VariableSaplingsSmall trees
PinaceaeFagaceaePinaceaeFagaceae
Coef. ± S.E.Coef. ± S.E.Coef. ± S.E.Coef. ± S.E.
(Intercept)2.50 ± 0.66***7.56 ± 0.50***4.93 ± 0.66***7.72 ± 0.34***
Overstory Mixed0.58 ± 0.15***0.17 ± 0.05***
Overstory Pine0.61 ± 0.17***0.54 ± 0.11***
sqrt (Total BA)0.07 ± 0.03*− 0.07 ± 0.02***0.11 ± 0.03***− 0.08 ± 0.02***
log (Temperature)−0.38 ± 0.17*−0.99 ± 0.13***−0.65 ± 0.16***−0.53 ± 0.11***
log (Precipitation)0.54 ± 0.09***0.31 ± 0.07***0.35 ± 0.09***
Wildfires0.30 ± 0.04***−0.14 ± 0.06*0.12 ± 0.04**
Grazing0.08 ± 0.05−0.25 ± 0.04***− 0.10 ± 0.04**
Pests
Wood extractions0.14 ± 0.06*−0.09 ± 0.05
Land tenure Public0.49 ± 0.32−0.04 ± 0.25
Land tenure Social0.13 ± 0.06*0.10 ± 0.04*
R2 marginal0.0540.0590.0450.022
R2 conditional0.1070.1110.0850.083
  1. Coefficient values are given relative to the reference level for each factor-type variable (Overstory = ‘Oak’, Land tenure = ‘Private’, and no/low disturbance level for all disturbance types), which implies that the estimate for the reference level of each factor is included in the intercept, and the coefficients for the additional (non-reference) factor levels indicate how they deviate from the overall intercept. State was included as a random factors (see text). Model selection was based on AIC. Some variables were log- or square-root (sqrt) transformed to ensure normality, as indicated below. Significance codes: * 0.05 < P < 0.01; ** 0.01 < P < 0.001; *** P < 0.001