Drought- and heat-induced regional tree mortality events around the world.

Brendan Choat was a co-author on a study recently published in PNAS. The study, lead by Bill Anderegg (University of Utah) discovered a strong link between the mortality of tree species resulting from drought and plant hydraulic traits. Data were gathered from 33 published studies of tree mortality that included 475 tree species and more than 760,000 individual trees. Mortality rates for each species were then compared to 10 tree physiological traits, searching for commonalities. The traits included wood density, rooting depth, and basic leaf characteristics as well as plant hydraulic traits such as vulnerability to embolism and sapwood specific conductivity. The results provide support for the hypothesis that hydraulic traits capture key mechanisms determining mortality and highlight that physiological traits can improve vegetation model prediction of tree mortality during climate extremes.

Congratulations to PhD student Jen Peters who was recently awarded a Student Research Grant from the Wet Tropics Management Authority! The title of Jen’s research grant is “Assessing Vulnerability to Water Limitation of Australian’s Tropical Rainforest” and will contribute to her thesis project examining the vulnerability of Australian forests to drought. This grant will fund her research at the Daintree Rainforest Observatory where she will characterize stem and leaf vulnerability to drought stress for the dominant tree canopy species.

Jen Peters (right) at the Daintree Rainforest study site.