Rhizosphere stoichiometry: are C : N : P ratios of plants, soils, and enzymes conserved at the plant species-level?
Article first published online: 4 OCT 2013
© 2013 The Authors. New Phytologist © 2013 New Phytologist Trust
Volume 201, Issue 2, pages 505–517, January 2014
How to Cite
Bell, C., Carrillo, Y., Boot, C. M., Rocca, J. D., Pendall, E. and Wallenstein, M. D. (2014), Rhizosphere stoichiometry: are C : N : P ratios of plants, soils, and enzymes conserved at the plant species-level?. New Phytologist, 201: 505–517. doi: 10.1111/nph.12531
- Issue published online: 18 DEC 2013
- Article first published online: 4 OCT 2013
- Manuscript Accepted: 27 AUG 2013
- Manuscript Received: 5 JUN 2013
- US National Science Foundation. Grant Number: DEB# 1021559
- US Department of Energy's Office of Science
- ecological stoichiometry;
- extracellular enzymes;
- microbial biomass;
- plant species;
- semiarid grassland;
- soil nutrients
- As a consequence of the tight linkages among soils, plants and microbes inhabiting the rhizosphere, we hypothesized that soil nutrient and microbial stoichiometry would differ among plant species and be correlated within plant rhizospheres.
- We assessed plant tissue carbon (C) : nitrogen (N) : phosphorus (P) ratios for eight species representing four different plant functional groups in a semiarid grassland during near-peak biomass. Using intact plant species-specific rhizospheres, we examined soil C : N : P, microbial biomass C : N, and soil enzyme C : N : P nutrient acquisition activities.
- We found that few of the plant species' rhizospheres demonstrated distinct stoichiometric properties from other plant species and unvegetated soil. Plant tissue nutrient ratios and components of below-ground rhizosphere stoichiometry predominantly differed between the C4 plant species Buchloe dactyloides and the legume Astragalus laxmannii. The rhizospheres under the C4 grass B. dactyloides exhibited relatively higher microbial C and lower soil N, indicative of distinct soil organic matter (SOM) decomposition and nutrient mineralization activities.
- Assessing the ecological stoichiometry among plant species' rhizospheres is a high-resolution tool useful for linking plant community composition to below-ground soil microbial and nutrient characteristics. By identifying how rhizospheres differ among plant species, we can better assess how plant–microbial interactions associated with ecosystem-level processes may be influenced by plant community shifts.