Disentangling the role of photosynthesis and stomatal conductance on rising forest water-use efficiency.

ABSTRACT: Multiple lines of evidence suggest that plant water-use efficiency (WUE)-the ratio of carbon assimilation to water loss-has increased in recent decades. Although rising atmospheric CO₂ has been proposed as the principal cause, the underlying physiological mechanisms are still being debated, and implications for the global water cycle remain uncertain. Here, we addressed this gap using 30-y tree ring records of carbon and oxygen isotope measurements and basal area increment from 12 species in 8 North American mature temperate forests. Our goal was to separate the contributions of enhanced photosynthesis and reduced stomatal conductance to WUE trends and to assess consistency between multiple commonly used methods for estimating WUE. Our results show that tree ring-derived estimat

SUBMITTER: Guerrieri R 

PROVIDER: S-EPMC6708355 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature