Leaf hydraulics

Collaborators: Lawren Sack (UCLA), Tom Buckley (University of Sydney), Andrew McElrone (UC Davis), Craig Brodersen (Yale U), Hervé Cochard (France), Steven Jansen (Germany).
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We are working on identifying the drivers of leaf hydraulic decline during water stress. We have developed methods to partition the response of water movement in the xylem vs. the outside-xylem pathways during dehydration. Using empirical approaches, novel imaging techniques and modelling, we are investigating the role of leaf venation and bundle sheath/mesophyll cells on leaf hydraulic decline.  We are currently working with the model plant Arabidopsis thaliana to understand the relationship of genes and hydraulics/anatomical traits to performance.

Plasticity and evolution of leaf traits

Collaborators: Lawren Sack (UCLA),  Jeremy Beaulieu (University of Arkansas)

We are very interested in understanding the mechanisms for leaf trait plasticity and how they evolved through time. We are currently completing a global database of leaf morphological and venation characteristics for >5000 species distributed worldwide, to understand the evolution of these traits across biomes. This will allow us for the first time, using evolutionary and comparative analyses, to test for the function behind the striking diversity observed in leaf size and venation architecture.

Species adaptation to drought

Collaborators: Lawren Sack (UCLA), Phil Rundel (UCLA), Rasoul Sharifi (UCLA)

We are interested in determining the anatomical and physiological drivers underlying species drought tolerance. We are currently working on quantifying the physiological and anatomical diversity within the genus Banksia (growing in a common garden in Ojai, CA), which includes very drought tolerant Australian species, extremely diverse in their leaf size and shape, and stomatal anatomy.

​Liana hydraulics

Collaborator: Stefan Schnitzer (Marquette University)

Lianas are increasing in abundance in neotropical forests, altering forest dynamics, composition and functioning. We are collaborating with the Schnitzer lab to help characterize liana leaf hydraulic design and physiology on BCI (Panama)  to understand why/how liana abundance is increasing  in these systems.