The Qualitative Properties For Some Type Of Population Models

The population dynamics model is a model used to express the relationship between the environment and the population,the population and the population.It can predict and reflect the development trend of a certain population and species and the influence factors of the population.By constructing the ecological model of the population and exploring the development law of the species by the dynamic model,it can promote the people to the ecology.The understanding of system and species population plays an indispensable role in developing resources,utilizing resources and regenerating resources.In this paper,an ecological system based on impulsive delay differential equation is mainly studied.By applying the principle of coincidence degree,the principle of differential equation comparison,the 3/2 criterion,the theory of topological degree and almost periodic ordinary differential equation theory,the dynamic properties of the time-delay predator-prey model and the time-delay Logistic model with impulse function are discussed,including the existence of the positive periodic solution.The persistence,global attractivity and the existence and uniqueness of almost periodic solutions of the system are presented.The full text structure is as follows:The first chapter introduces the background and current situation of the study,and briefly summarizes the main work of the paper.In the second chapter,the sufficient conditions for the existence of positive periodic solutions for a class of nonlinear impulsive delay Hassell-Varley type predator-prey systems are studied by coincidence degree theory.In the third chapter,by applying the principle of comparison,the sufficient conditions for the uniform persistence of a Logistic type system with impulsive delay are obtained,and the sufficient conditions of the global attractiveness of the system are given by using the 3/2-criterion.In the last chapter,the sufficient condition for the existence of almost periodic solutions of impulsive delay Logistic type systems is obtained by using almost periodic ordinary differential equation theory.