Impact of selective grazing on the dynamics of a diffusive plankton model with component Allee effect and additional food

Abstract

In order to explore the pattern formation of non-toxic phytoplankton, toxin-producing phytoplankton, and zooplankton, a spatiotemporal plankton model is formulated by incorporating the component Allee effect, additional food, and selective grazing. For the non-spatial scenario, the qualitative analyses and numerical simulations show that the system admits rich dynamics such as Hopf bifurcation and alternative stable states. For the spatial model, the stability analyses demonstrate that the moderate component Allee effect and adequate additional food promote stable coexistence. Furthermore, our findings illustrate that selective grazing facilitates toxin-producing phytoplankton biomass. Low grazing selectivity decreases zooplankton biomass. Moderate grazing selectivity contributes to coexistence. Excessive grazing selectivity promotes the rapid reproduction of toxin-producing phytoplankton and leads to spatiotemporal chaos. In addition, the variations in the component Allee effect, additional food, and grazing selectivity give rise to the transitions of spatial patterns, which shed valuable insights into controlling plankton distribution.