CAREER: Unveiling the role of hillslope hydrology in mediating ecosystem response to drought

Forest ecosystems provide important resources to humans but face significant challenges from high temperatures and droughts. It is urgent to understand how forests respond to these stresses so we can improve planning and management. This project seeks to understand how trees may slow their growth or die during drought and how important access to deep water is, depending on where trees are growing across the landscape. The researchers will use many tools, including direct forest measurements and satellite observations. Computer models will be used to understand those observations and make forecasts of how forests might behave in the future. The research will be used to improve teaching of students of all ages and seek to expose them to new areas like computer science, ecology and hydrology. Results from this project will be shared widely with the research community and incorporated into classroom activities. The project will promote the participation, recruitment, and retention of students at all educational levels from K-12 to Ph.D. via a series of formal interdisciplinary opportunities for coursework, collaboration, and networking. Elevated forest mortality triggered by extreme drought and heat has been globally observed, with manifold consequences for ecosystem structure, function, and feedback to climate. Predicting tree mortality in response to climate extremes is a long-standing and unresolved scientific problem. The project will evaluate novel hypotheses about forest mortality by assessing the impacts of hydrology on ecosystem function via the expected interaction between groundwater access and plant physiological traits. Key drivers and mechanisms identified from the research will inform the development of Earth system models, paving the way for improved model representation and predictive abilities. This project is jointly funded by the Ecosystem Science Cluster in the Directorate for Biological Sciences and the Water, Landscape, and Critical Zone Processes program in the Directorate for Geosciences. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.