UH Manoa botany professor awarded prestigious grant to study hydraulic design of leaves

Study to focus on native Hawaiian plant lineages; mentorship program to be developed for Hawaiian students interested in plant research

HONOLUU — One of the largest biology awards given to support the early career development activities of teachers and scholars has been awarded to Lawren Sack, assistant professor of Botany at the University of Hawaiʻi at Mānoa. Sack received an $887,989 grant from the National Science Foundation‘s Faculty Early Career Development (CAREER) Program for a five-year study of the coordination of leaf hydraulics, structure and gas exchange.

The study of leaf hydraulics involves the use of new techniques to measure the movement of water through a leaf‘s vein network and membranes. Sack and his colleagues have recently found that the leaf is a major bottleneck in the movement of water through the whole plant, and that leaf hydraulic properties would be a strong factor in determining growth rates and responses to the environment.

The grant will support Sack‘s work in explaining how strong a limit the leaf hydraulic system imposes on whole-plant performance, and how and why leaves differ across species and environments in vein architecture and in other aspects of leaf anatomy and function.

"We are after general principles of leaf design that have developed as optimality solutions during evolution," said Sack.

Sack‘s study will focus on native Hawaiian plant lineages that have diversified in leaf structure and function, including ferns and flowering plants. Native Hawaiian species and invasive species will be studied in common gardens and across the dramatic natural moisture and soil age gradients of Hawaiʻi. "This work has the potential to contribute toward prediction of the impacts of climate change on plant function, and in particular, their responses to drought," said Sack.

Sack also plans to collaborate with other experts inside and outside of the university to develop a database on the structure, physiology and ecology of the entire Hawaiian flora, including native and alien plants, to understand their biology and to predict the impacts on plants of environmental change. In this work, Sack hopes to create new resources that will be made available to researchers worldwide.

The research will be integrated with undergraduate and graduate courses, and will involve the creation of a new mentorship program to provide increased access for native Hawaiians to scientific training and careers, based on the study of unique Hawaiian flora.

Sack joined the Botany Department in the College of Natural Sciences at UH Mānoa as an assistant professor in August 2003. Previously, he was a postdoctoral researcher in the Department of Organismic and Evolutionary Biology at Harvard University from 2001 to 2003. Sack received his Ph.D. degree in plant physiology and ecology from Cambridge University in 2001.

For more information about Sack and his work, visit http://www.botany.hawaii.edu/faculty/sack/.

About CAREER

The Faculty Early Career Development (CAREER) Program is a Foundation-wide activity that offers the National Science Foundation's most prestigious awards in support of the early career-development activities of those teacher-scholars who most effectively integrate research and education within the context of the mission of their organization. Such activities should build a firm foundation for a lifetime of integrated contributions to research and education.