Fig. 1: Conceptual representation of water pools within the soil–plant continuum and associated water extraction methods.
From: Demystifying stable hydrogen isotope offsets between plants and source waters
A The “two plant water pools” concept; B The “three soil water pools” concept;, C The correct water pools within the soil-plant continuum deriving from diverse flow heterogeneities. The water extraction methods and their corresponding extraction range concerning water potential, pore diameter, and different water pools. The soil water extraction methods, along with their corresponding ranges of matric potential and pore diameter, were adapted from Sprenger et al.60. The “two plant water pools” concept refers to the sap flow water pool within xylem conduits and surrounding non-conducting xylem tissue water. The “three soil water pools” concept refers to gravitational soil water, plant-available soil water, and hygroscopic soil water. The plant-available soil water pool and the sap flow water pool within plant xylem conduits are recognized as appropriate water pools for isotope-based ecohydrological investigations.
