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Title: Predators in the plant–soil feedback loop: aboveground plant‐associated predators may alter the outcome of plant–soil interactions

Plant–soil feedback (PSF) can structure plant communities, promoting coexistence (negativePSF) or monodominance (positivePSF). At higher trophic levels, predators can alter plant community structure by re‐allocating resources within habitats. When predator and plant species are spatially associated, predators may alter the outcome ofPSF. Here, I explore the influence of plant‐associated predators onPSFusing a generalised cellular automaton model that tracks nutrients, plants, herbivores and predators. I explore key contingencies in plant–predator associations such as whether predators associate with live vs. senesced vegetation. Results indicate that plant‐associated predators shiftPSFto favour the host plant when predators colonise live vegetation, but the outcome ofPSFwill depend upon plant dispersal distance when predators colonise dead vegetation. I apply the model to two spider‐associated invasive plants, finding that spider predators should shiftPSFdynamics in a way that inhibits invasion by one forest invader, but exacerbates invasion by another.

Publication Date:
Journal Name:
Ecology Letters
Page Range or eLocation-ID:
p. 646-654
Sponsoring Org:
National Science Foundation
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