The Science

Fine roots play important roles acquiring soil nutrients and water for plant growth. However, it has been difficult to determine how traits of fine roots change across environments and how these changes impact plant and ecosystem processes.

The Impact

The scientists highlight barriers limiting knowledge of how fine roots work in ecosystems and, importantly, suggest tractable ways in which to possibly overcome those barriers. Refocusing their efforts to measure multiple aspects of roots traits and function in ways that can be rigorously compared across species will rapidly improve understanding of terrestrial ecosystems.

Summary

Trait-based approaches provide a useful framework to investigate plant strategies for resource acquisition, growth, and competition, as well as plant impacts on ecosystem processes. Despite significant progress capturing trait variation within and among stems and leaves, identification of trait syndromes within fine-root systems and between fine roots and other plant organs is limited. This study discusses three underappreciated areas where focused measurements of fine-root traits can make significant contributions to ecosystem science. These areas include assessment of spatiotemporal variation in fine-root traits, integration of mycorrhizal fungi into fine root–trait frameworks, and the need for improved scaling of traits measured on individual roots to ecosystem-level processes. Progress in each of these areas is providing opportunities to revisit how belowground processes are represented in terrestrial biosphere models. Targeted measurements of fine-root traits with clear linkages to ecosystem processes and plant responses to environmental change are strongly needed to reduce empirical and model uncertainties. Further identifying how and when suites of root and whole-plant traits are coordinated or decoupled will ultimately provide a powerful tool for modeling plant form and function at local and global scales.

Principal Investigator

Luke McCormack
University of Minnesota
mltmcc@gmail.com

Program Manager

Daniel Stover
U.S. Department of Energy, Biological and Environmental Research (SC-33)
Environmental System Science
daniel.stover@science.doe.gov

Funding

The authors acknowledge support from the Terrestrial Ecosystem Sciences (TES) program of the Office of Biological and Environmental Research (BER), within the U.S. Department of Energy (DOE) Office of Science; the New Phytologist Trust; and the Chinese Academy of Sciences (CAS) for supporting the workshop where the initial ideas for this manuscript were developed.

References