Dynamics Of Plant-pollinator-herbivore System

The interactions among plant,pollinator and herbivore populations are complex,and as well as predation and mutualism,there are also higher-order interactions.Herbivores can not only directly reduce plant density,but also induce changes in plant metabolism,affecting the strength of interactions between plants and pollinators through foraging behaviour.A model of plant-pollinator-herbivore is formulated to explore the effects of higher-order interactions on system dynamical behaviours based on Holling’s time budget argument.Through qualitative analysis,we analyze the dissipativity of the system and provide conditions for the existence and stability of equilibria,then we take the disturbance parameter describing higher-order interactions as the bifurcation parameter and obtain conditions of the existence of Hopf bifurcation at positive equilibria.Moreover,the key parameters affecting stable population sizes are identified by using global sensitivity analysis.According to numerical simulation,it is explored that the influence of the disturbance parameter on population dynamics and the joint influence of the disturbance parameter and other parameters.The results reveal that higher-order interactions can affect the stability of the system and also cause complex dynamical behaviours.