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 (negative PSF) or monodominance (positive PSF). 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 of PSF. Here, I explore the influence of plant-associated predators on PSF using a generalized 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 shift PSF to favor the host plant when predators colonize live vegetation, but the outcome of PSF will depend upon plant dispersal distance when predators colonize dead vegetation. I apply the model to two spider-associated invasive plants, finding that spider predators should shift PSF dynamics in a way th...