“…It accounts for over 60% of total water flux into the atmosphere (Good et al, 2015;Jasechko et al, 2013). In forest ecosystems, transpiration is the main component of ecosystem water use (Wang et al, 2021), and can be measured through tree sap flux (SF) (Bosch et al, 2014;Granier, 1987;Tanaka et al, 2023;Zeng et al, 2022). Although the main environmental factors controlling SF vary with regions and tree species, the most widely recognized factors include incoming shortwave radiation (Rsi), air temperature (Ta), relative humidity (RH) or vapor pressure deficit (VPD) and soil water content (SWC) (Abreu et al, 2022;Ghimire et al, 2014;Han et al, 2019;Song et al, 2020).…”