Covariate correlations
Relationships between forest structure and climate variables were weakly correlated, with the absolute values of all Spearman rank correlation coefficients below 0.6 (Figure 3). Correlation coefficients revealed that the relationship between precipitation and temperature were weakly positive and significant (R2 = 0.25, p-value = <0.001), but neither were strongly correlated with three-dimensional forest structure or productivity. For example, maximum canopy height was not correlated with precipitation (R2 = -0.01, p-value = 0.88), but it was weakly correlated with temperature (R2 = 0.39, p-value = <0.001). Most forest structure variables were weakly correlated with each other (Figure 3; Table S4). For example, maximum canopy height had positive correlations with the coefficient of variation in LAD vertically (R2 = 0.36, p-value = <0.001) and horizontally (R2 = 0.17, p-value = <0.001) and with Shannon’s Diversity of LAD (R2 = 0.54, p-value <0.001).