
Plant Biology, Год журнала: 2024, Номер unknown
Опубликована: Дек. 25, 2024
Temperate mixed forests are currently experiencing severe drought conditions and face increased risk of degradation. However, it remains unclear how critical tree physiological functions such as sap flow density (SFD) water deficit (TWD, defined reversible stem shrinkage when is depleted), respond to extreme environmental they interact under dry conditions. We monitored SFD TWD three co-occurring European species (Fagus sylvatica, Fraxinus excelsior Acer pseudoplatanus) in conditions, using high temporal resolution flow, dendrometer, measurements. Species-specific responses soil drying did not differ significantly, while was significantly higher F. excelsior. Inter-specific differences wood anatomy use strategies consistently explain these responses. responded both moisture content (SWC) during wet (SWC ≥ 0.2) < phases, with responding more strongly. There a significant correlation for vapour pressure (VPD) only the phase, VPD phase. During incoming PPFD correlated all species, sylvatica negatively SFD, showing hysteresis effects from which decreasing sigmoidal phase along gradient observed. The nonlinear correlations between may result time lag two variables, their different sensitivities SWC intensities. conclude that, stress, cannot be used proxy or vice versa.
Язык: Английский