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In this paper, a nonautonomous stochastic food-chain system with functional response and impulsive perturbations is studied. By using Itô's formula, exponential martingale inequality, differential inequality and other mathematical skills, some sufficient conditions for the extinction, nonpersistence in the mean, persistence in the mean, and stochastic permanence of the system are established. Furthermore, some asymptotic properties of the solutions are also investigated. Finally, a series of numerical examples are presented to support the theoretical results, and effects of different intensities of white noises perturbations and impulsive effects are discussed by the simulations. [ABSTRACT FROM AUTHOR]

In this paper, we study the dynamic behaviors of a non-autonomous single-species model subject to impulsive and random perturbations. We first investigate the existence and uniqueness of the globally positive solution of the model. Secondly, a good understanding of the extinction, non-persistence in the mean, weak persistence, persistence in the mean and stochastic permanence of the model is obtained. Thirdly, we further examine the asymptotic pathwise estimation. Fourthly, it is shown that the model is globally attractive under some appropriate conditions. Finally, numerical simulations are presented to justify the analytical results. [ABSTRACT FROM AUTHOR]

In the real world, the population systems are often subject to white noises and a system with such stochastic perturbations tends to be suitably modeled by stochastic differential equations. This paper is concerned with the dynamic behaviors of a delay stochastic competitive system. We first obtain the global existence of a unique positive solution of system. Later, we show that the solution of system will be stochastically ultimate boundedness. However, large noises may make the system extinct exponentially with probability one. Also, sufficient conditions for the global attractivity of system are established. Finally, illustrated examples are given to show the effectiveness of the proposed criteria. [ABSTRACT FROM AUTHOR]

This paper is concerned with a nonautonomous single-species model, in which the population dynamics is affected by impulsive perturbations and environmental noise. Sufficient conditions for the extinction, stochastic permanence, and global attractivity of system are obtained, respectively. The above results reveal that the white noise plays a very important role in the dynamic behaviors. However, it is found that the bounded impulse does not affect the above properties. Some numerical simulation results are presented to support the analytical findings. [ABSTRACT FROM AUTHOR]

This paper presents a nonautonomous impulsive stochastic differential model of competition between species which contains the classic two-species competitive Lotka–Volterra model as a special case. With the theory of impulsive stochastic differential equations, a good understanding of stochastic permanence and extinction of system is obtained. Two specific numerical examples are presented to support the analytical results. Conclusions are also given. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, an almost periodic system of impulsive differential equations used in modeling two-species in competition is considered. By the comparison between the solutions of impulsive system and the corresponding non-impulsive system and constructing Lyapunov function, sufficient conditions ensuring the uniformly asymptotic stability of a unique positive almost periodic solution of the system are derived. Finally, an example and its corresponding numerical simulations are presented to explain our theoretical results. [Copyright &y& Elsevier]

Abstract: A periodic single-species model with periodic impulsive perturbations was investigated. By using Brouwer’s fixed point theorem and the Lyapunov function, sufficient conditions for the existence and global asymptotic stability of positive periodic solutions of the system were derived. Numerical simulations were presented to verify the feasibilities of our main results. [Copyright &y& Elsevier]

Abstract: In this paper, we consider the dynamic behavior of an impulsive delay differential equation model with the effects of interspecific allelopathic interaction. A good understanding of the permanence, extinction and the existence of positive periodic solutions is gained. It turns out that the impulsive controls play a crucial role in shaping the above dynamics of the system. Numerical simulations are presented to substantiate the analytical results. [Copyright &y& Elsevier]

In this paper we study the existence of positive periodic solutions for a class of neutral type competitive system with delay. Applying the continuation theorem of coincidence degree theory, a general criteria on the existence of positive periodic solutions are established. Some the related results are generalized and improved. It is shown that the arguments delays have no effect on the existence positive periodic solution of system. [Copyright &y& Elsevier]