Plant and Soil

, Volume 359, Issue 1, pp 233–244

Root carbon flow from an invasive plant to belowground foodwebs

  • Mark A. Bradford
  • Michael S. Strickland
  • Jayna L. DeVore
  • John C. Maerz
Regular Article

DOI: 10.1007/s11104-012-1210-y

Cite this article as:
Bradford, M.A., Strickland, M.S., DeVore, J.L. et al. Plant Soil (2012) 359: 233. doi:10.1007/s11104-012-1210-y

Abstract

Aims

Soil foodwebs are based on plant production. This production enters belowground foodwebs via numerous pathways, with root pathways likely dominating supply. Indeed, root exudation may fuel 30–50 % of belowground activity with photosynthate fixed only hours earlier. Yet we have limited knowledge of root fluxes of recent-photosynthate from invasive plants to belowground foodwebs.

Methods

Using stable isotopes, we quantify the proportion of recent-photosynthate transferred belowground from the invasive grass Microstegium vimineum A. Camus, a widespread invader of forest understory. Given its minimal root biomass (∼8 % of individual mass), we expected exudation to contribute little to belowground foodwebs.

Results

Within 2 days of 13C-labeling, we recover ∼15 % of photosynthate carbon in microbial biomass. Recovery in root and dissolved organic carbon pools is consistently low (<2 %), suggesting these pools operate as ‘pipelines’ for carbon transport to soil microbes. The recovery of the label in wolf spiders – forest floor predators that feed on soil animals – highlights that root inputs of recent photosynthate can propagate rapidly through belowground foodwebs.

Conclusions

Our results suggest that root carbon-exudation, an unexplored process of invasive grass inputs to forest foodwebs, may be an important pathway through which invasive species affect the structure and function of recipient ecosystems.

Keywords

Detrital foodwebSoil foodwebSoil organismsExotic speciesMicrostegium vimineumRhizodeposition

Copyright information

© Springer Science+Business Media B.V. 2012

Authors and Affiliations

  • Mark A. Bradford
    • 1
  • Michael S. Strickland
    • 1
  • Jayna L. DeVore
    • 2
  • John C. Maerz
    • 2
  1. 1.School of Forestry and Environmental StudiesYale UniversityNew HavenUSA
  2. 2.Warnell School of Forestry and Natural ResourcesUniversity of GeorgiaAthensUSA