Fig. 3.

Changes in BAI and Δ¹⁸O_LW, and physiological link between Δ¹⁸O_LW and g_s. Slopes (±SE) of the temporal changes in BAI (A) and Δ¹⁸O_LW (B) for the investigated species. Slopes significantly different from zero (SI Appendix, Table S7) are denoted with different colors, according to the P values. The black circle denotes sites where VPD increased. The vertical blue line separates mesic from xeric sites. C summarizes the physiological link between the Δ¹⁸O_LW and changes in transpiration (T) and g_s. The arrows indicate when the slope of Δ¹⁸O_LW was either greater than or less than zero.