Fine root decomposition constitutes a critical yet poorly understood flux of carbon and nutrients in terrestrial ecosystems. Here, we present the first large-scale synthesis of species trait effects on the early stages of fine root decomposition at both global and local scales. Based on decomposition rates for 279 plant species across 105 studies and 176 sites, we found that mycorrhizal association and woodiness are the best categorical traits for predicting rates of fine root decomposition. Consistent positive effects of nitrogen and phosphorus concentrations and negative effects of lignin concentration emerged on decomposition rates within sites. Similar relationships were present across sites, along with positive effects of temperature and moisture. Calcium was not consistently related to decomposition rate at either scale. While the chemical drivers of fine root decomposition parallel those of leaf decomposition, our results indicate that the best plant functional groups for predicting fine root decomposition differ from those predicting leaf decomposition.
Bibliographical noteFunding Information:
We thank Christopher Walter, Alex Strauss, Becka Walling, Allison Gill and Leno Smith for helpful feedback throughout the preparation of the manuscript. The editor and two anonymous reviewers helped to greatly improve the final version. John Fieberg provided valuable advice regarding statistical approaches and Ethan Butler provided data for the moisture index. Financial support was provided by NSF DEB grants #1554375 to P. G. Kennedy and 1754679 to M. L. McCor-mack and P. G. Kennedy.
© 2019 John Wiley & Sons Ltd/CNRS
- Carbon cycling
- MANE framework
- nutrient cycling
- organic matter
- plant economics spectrum
- plant functional traits
- plant litter
- soil organic matter