Theoretical Ecology

, Volume 8, Issue 3, pp 297–312

Interactions among mutualism, competition, and predation foster species coexistence in diverse communities

  • Benedicte Bachelot
  • María Uriarte
  • Krista McGuire
ORIGINAL PAPER

DOI: 10.1007/s12080-015-0251-2

Cite this article as:
Bachelot, B., Uriarte, M. & McGuire, K. Theor Ecol (2015) 8: 297. doi:10.1007/s12080-015-0251-2

Abstract

In natural systems, organisms are simultaneously engaged in mutualistic, competitive, and predatory interactions. Theory predicts that species persistence and community stability are feasible when the beneficial effects of mutualisms are balanced by density-dependent negative feedbacks. Enemy-mediated negative feedbacks can foster plant species coexistence in diverse communities, but empirical evidence remains mixed. Disparity between theoretical expectations and empirical results may arise from the effects of mutualistic mycorrhizal fungi. Here, we build a multiprey species/predator model combined with a bidirectional resource exchange system, which simulates mutualistic interactions between plants and fungi. To reach population persistence, (1) the per capita rate of increase of all plant population must exceed the sum of the negative per capita effects of predation, interspecific competition, and costs of mycorrhizal association, and (2) the per capita numerical response of enemies to mycorrhizal plants must exceed the magnitude of the per capita enemy rate of mortality. These conditions reflect the balance between regulation and facilitation in the system. Interactions between plant natural enemies and mycorrhizal fungi lead to shifts in the strength and direction of net mycorrhizal effects on plants over time, with common plant species deriving greater benefits from mycorrhizal associations than rare plant species.

Keywords

Prey–predator model Food web dynamics Mutualism Janzen-Connell Mycorrhizal associations 

Supplementary material

12080_2015_251_MOESM1_ESM.docx (150 kb)
ESM 1(DOCX 149 kb)

Copyright information

© Springer Science+Business Media Dordrecht 2015

Authors and Affiliations

  • Benedicte Bachelot
    • 1
  • María Uriarte
    • 1
  • Krista McGuire
    • 2
  1. 1.Department of Ecology, Evolution and Environmental BiologyColumbia UniversityNew YorkUSA
  2. 2.Department of Biology, Barnard CollegeColumbia UniversityNew YorkUSA