Ecosystems

, Volume 14, Issue 1, pp 156–167

Plants Mediate the Sensitivity of Soil Respiration to Rainfall Variability

  • Zachary T. Aanderud
  • Donald R. SchoolmasterJr.
  • Jay T. Lennon
Article

DOI: 10.1007/s10021-010-9401-y

Cite this article as:
Aanderud, Z.T., Schoolmaster, D.R. & Lennon, J.T. Ecosystems (2011) 14: 156. doi:10.1007/s10021-010-9401-y

Abstract

Soil respiration from grasslands plays a critical role in determining carbon dioxide (CO2) feedbacks between soils and the atmosphere. In these often mesic systems, soil moisture and temperature tend to co-regulate soil respiration. Increasing variance of rainfall patterns may alter aboveground–belowground interactions and have important implications for the sensitivity of soil respiration to fluctuations in moisture and temperature. We conducted a set of field experiments to evaluate the independent and interactive effects of rainfall variability and plant–soil processes on respiration dynamics. Plant removal had strong effects on grassland soils, which included altered CO2 flux owing to absence of root respiration; increased soil moisture and temperature; and reduced availability of dissolved organic carbon (DOC) for heterotrophic respiration by microorganisms. These plant-mediated effects interacted with our rainfall variability treatments to determine the sensitivity of soil respiration to both moisture and temperature. Using time-series multiple regression, we found that plants dampened the sensitivity of respiration to moisture under high variability rainfall treatments, which may reflect the relative stability of root contributions to total soil respiration. In contrast, plants increased the sensitivity of respiration to temperature under low variability rainfall treatment suggesting that the environmental controls on soil CO2 dynamics in mesic habitats may be context dependent. Our results provide insight into the aboveground–belowground mechanisms controlling respiration in grasslands under variable rainfall regimes, which may be important for predicting CO2 dynamics under current and future climate scenarios.

Key words

CO2heterotrophic respirationpulseroot respirationtime-seriessensorsmicrobialclimate changeprecipitation

Supplementary material

10021_2010_9401_MOESM1_ESM.pdf (314 kb)
(PDF 315 kb)

Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • Zachary T. Aanderud
    • 1
    • 2
  • Donald R. SchoolmasterJr.
    • 1
  • Jay T. Lennon
    • 1
    • 3
  1. 1.W. K. Kellogg Biological StationMichigan State UniversityHickory CornersUSA
  2. 2.Department of Plant and Wildlife SciencesBrigham Young UniversityUtahUSA
  3. 3.Department of Microbiology and Molecular GeneticsMichigan State UniversityHickory CornersUSA