A Research Agenda for Improving the Representation of Plant Hydrodynamics in Earth System Models
Authors
Jeffrey Dukes1* (jdukes@carnegiescience.edu), Chonggang Xu2, Elin Jacobs3, Richard Phillips4, Kimberly Novick4, Yilin Fang5, Chang Liao5, Daniel Beverly4, Indira Paudel1
Institutions
1Carnegie Institution for Science, Stanford, CA; 2Los Alamos National Laboratory, Los Alamos, NM; 3Purdue University, West Lafayette, IN; 4Indiana University–Bloomington, IN; 5Pacific Northwest National Laboratory, Richland, WA
Abstract
Plant traits linked to drought tolerance vary widely among different species but also among and even within populations of a single species. This variation is driven partly by antecedent moisture conditions and partly by the pedoclimatic conditions in which the plants grow. While researchers have recently implemented frameworks for simulating plant hydraulics in Earth system models, the frameworks depend on fixed trait values of variable quality, and the data needed to assess and validate these new models are largely lacking. Here, the team discusses how models simulate plant hydraulics, focusing on their strengths, weaknesses, and data needs, and identifies data gaps that limit confidence in their output. Researchers identify field and laboratory research needs related to these models and model evaluation workflows that can build confidence in models’ ability to represent plant responses to current and future environmental conditions. To enable more realistic simulation of plant hydraulic responses to water stress in models, the research community should provide model-compatible datasets of key plant hydraulic traits and status for model evaluation, parameterization, and validation. Researchers should use these data to pinpoint ecosystem responses to a changing hydroclimate by addressing both long-term climatic drying and episodic extreme droughts.