Figure 2: Mean (±SE) leaf water potential at predawn
(Ψpd), light-saturated net photosynthesis
(Anet), and stomatal conductance (gs)
for each sampling date in 2021 and 2022 for P. nigra , P.
sylvestris , Q. faginea , and Q. ilex in monospecific
(red), monofunctional (orange), multifunctional (light blue) and
four-species mixture plots (dark blue). The stars indicate significant
differences between mixed and monospecific plots at each sampling date
(*0.05≥P>0.01; **0.01≥P>0.001; ***P≥0.001).