Asymptotic and transient dynamics in predator-prey systems with spatial and temporal heterogeneity

点击翻译按钮获取中文摘要

This proposed research program will: (1) study the fear induced interspecific and intraspecific interactions in food-web systems; (2) explore the temperature-dependent phenology in predator-prey systems; (3) study the transient behavior in population dynamics. For (1), the focus will be two-fold: I will study both the competition outcome of species under indirect predation risk and the cascading effect of fear in ecological systems with more than two trophic levels. The models I develop in (1) will extend our previous results of the predator-prey systems with fear effect to systems involving spatial and temporal heterogeneity. This will lead to a thorough examination of the fear effect in the meta community, enrich our understanding of how species interact, and facilitate implementing appropriate strategies for ecosystem management. For (2), the focus will be on studying how temperature-dependent phenological events affect species' spatial distribution in a seasonal environment. Phenological events such as, emergence time or reproduction, impact when and for how long prey and predator interact and are subject to environmental variations such as the climatic change. Moreover, for a large class of species, the dispersal patterns vary significantly among different seasons. I plan to formulate seasonal models that combine the two effects in a mechanistic approach and study their impact on species persistence and spatial distribution. This will deepen our recognition of how climatic change deteriorates ecosystem biodiversity. For (3), the focus will also be two-fold: I will explore how systems respond to perturbations in short and intermediate time scales and I will investigate the underlying mechanisms that induce abrupt change of solutions from one state to another, such as the jump between low densities and high densities in population dynamics models, before the asymptotic convergence. I will also apply the obtained results on transient dynamics to ecological systems and infectious disease models, such that short-term predictions of the population density variation or disease spread can be made.