Plant-Soil Feedbacks as Bimatrix Evolutionary Games

Bimatrix evolutionary games are used to model the way Plant-Soil Feedbacks (PSFs) influence the competition between plant species growing in the same soil. This feedback refers to the impact on plant growth caused by the plant’s ability to modify soil conditions, whether abiotic or biotic. Along with a review on the existing literature of modelling PSFs from an Evolutionary Game Theory point of view, we introduce our own contribution on the field, generalising the current models. Our game describes the direct interaction between n plants and their n species-specific soil communities and its implied effect to the plants’ competition. For \(n>2\) $n>2$ , we treat numerically the Nash Equilibria of the game to find evidence for the possible stable states of the induced population dynamics. Together with a theoretical analysis based on well-known Evolutionary Game Theory results, we address the high complexity of the dynamical system and determine whether PSFs favour the coexistence of species or lead to the absolute dominance of one species. In fact, our results strengthen the general belief that negative PSFs are necessary for plants’ biodiversity.