Effect of gender on sap‐flux‐scaled transpiration in a dominant riparian tree species: Box elder (Acer negundo)

摘要: [1] Acer negundo is a dioecious riparian tree species with spatial segregation of the sexes along soil moisture gradients. Females are typically more common in wet sites streams (typically F/M � 1.6), whereas males drier away from 0.6). Spatial between may develop because higher reproductive cost females compared to males. If so, female trees would be under stronger selection maximize resource uptake, and therefore likely occur at greater frequencies high resources (i.e., streamsides), increase rates acquisition water nutrients). The leads hypothesis that male individuals have varying influence on ecosystem evapotranspiration. To address this, stem sap flux was measured mature streamside (� 1 m stream channel) nonstreamside (>1 occurring Red Butte Canyon near Salt Lake City, Utah, during 2004 growing season. Despite having similar predawn midday potentials, density 76% than (P < 0.0001), while 19% 0.0001). Mean daily all A. populations highly correlated mean vapor pressure deficit moderately photosynthetic active radiation = 0.0263). At watershed scale, contributed 20 21% respectively estimated 1.7 mm d transpiration dominant vegetation streamsides (estimated scaled measurements Canyon). Male 31 46% 8.0 adjacent channel. Results this investigation show population structure has direct consequences ET, particularly margins. Shifts therefore, profound impacts several ecohydrological processes including discharge, biogeochemical cycling, productivity.