Table 4 Mixed effects logistic regression model coefficients (standard error in parentheses), raw output from glmer {lme4}, R version 3.5.2. P values denoted with asterisks (** < 0.01, * < 0.05, . < 0.1), alpha level 0.10
Variable | White Oak | Chestnut Oak | Northern Red Oak | Black Oak | Pignut Hickory |
|---|---|---|---|---|---|
Intercept | −1.128 (±3.995) | −0.844 (5.761) | −17.087 (±6.142)** | −12.183 (±18.762) | 2.420 (±6.837) |
Basal area of tree 1990s (m2∙ha−1) | − 0.148 (±0.124) | − 0.171 (±0.188) | − 0.264 (±0.160) | −0.386 (±0.295) | 0.802 (±0.502) |
Basal area of plot 1990s (m2∙ha− 1) | −0.087 (±0.048). | 0.087 (±0.046). | 0.045 (±0.048) | −0.127 (±0.110) | 0.141 (±0.077). |
Age (years) | 0.015 (±0.020) | 0.000 (±0.021) | 0.055 (±0.025)* | 0.022 (±0.038) | −0.034 (±0.029) |
Depth of solum (centimeters) | −0.014 (±0.011) | 0.020 (±0.024) | −0.058 (±0.023)* | −0.027 (±0.025) | 0.019 (±0.013) |
B horizon acidity (pH) | 0.368 (±0.492) | −0.610 (±0.723) | 0.958 (±0.576). | 3.241 (±3.387) | −1.272 (±0.907) |
Slope percent | 0.018 (±0.019) | −0.026 (±0.026) | 0.025 (±0.025) | −0.016 (±0.029) | −0.011 (±0.027) |
Slope aspect (cosine-transformed, TASP) | −0.067 (±0.850) | 0.223 (±0.889) | 4.515 (±1.720)** | 0.086 (±1.652) | 0.891 (±1.256) |
Slope position (prop. distance to ridge, PDR) | 0.493 (±1.973) | −2.641 (±3.408) | 12.750 (±4.524)** | −1.609 (±3.434) | −1.404 (±2.769) |
TASP:PDR | −1.807 (±1.684) | 0.820 (±2.25) | −8.266 (±3.266)* | −0.344 (±3.353) | 2.638 (±2.740) |