Fig 6. Seasonal changes in pressure volume parameters and midday leaf water potential.
The effects of the independent variables (species, sampling month, and their interaction as fixed effects) on the dependent variables (each pressure-volume parameter) were evaluated using a linear mixed model [69]. Type III tests were performed for fixed effects (Wald-type test). Significant interspecific differences were on Ψtlp and Ψmd (P < 0.0001, Type III test, Table 2). Effect of the month was also significant for all tested pressure-volume parameters (P < 0.0001, Type III test, Table 2). Asterisk in the figure indicates significant differences between species in each month (ANOVA, *, P < 0.05; **, P < 0.01; ***, P < 0.001; ns, not significant). The bars indicate standard division.