CHANCE AND CHAOS IN POPULATION BIOLOGY - MODELS OF RECURRENT EPIDEMICS AND FOOD-CHAIN DYNAMICS
CHANCE AND CHAOS IN POPULATION BIOLOGY - MODELS OF RECURRENT EPIDEMICS AND FOOD-CHAIN DYNAMICS
复制标题
DOI：
10.1016/0960-0779(94)90028-0
复制
发表时间：
1994-07-01
影响因子：
7.8
通讯作者：
DREPPER, FR
中科院分区：
文献类型：
--
作者：
ENGBERT, R;DREPPER, FR
尽管某些生态系统的行为复杂，但它们的动力学可以用确定性的运动规律来解释。这显然在理论上是可能的，因为对生态系统动力学的演绎方法导致非线性模型，甚至非常简单的模型生态系统通常产生丰富的动力学谱，范围从共存的周期性制度到混沌行为。本文通过两个实例分析了确定性非线性动力学与人口统计学随机性之间复杂的相互作用。首先，对生态混乱的研究引起了人们对在人口密集的中心地区反复爆发的儿童流行病的分析，特别是麻疹感染的分析。第二个例子是一个三物种食物链的隔间模型，在这个模型中，由于短暂的混乱，可以观察到种群的突然消失。我们的分析支持了种群动态中混沌的合理性。然而，随着种群规模的减小（波动的增加），混沌和随机性的区分变得越来越困难。确定性动力学和随机波动之间的相互作用，例如由于种群的整数结构或噪声环境，建议结合非线性动力系统理论和随机过程的方法进行分析。
In spite of their complex behaviour the dynamics of some ecological systems may be explained by deterministic laws of motion. This is clearly theoretically possible, because deductive approaches to the dynamics of ecological systems lead to nonlinear models and even very simple model ecosystems generate typically a rich spectrum of dynamics, ranging from coexisting periodic regimes to chaotic behaviour. The present study analyses the complex interplay between deterministic nonlinear dynamics and demographic stochasticity using,two examples. Firstly, the search for chaos in ecology has drawn much attention to the analysis of recurrent outbreaks of childhood epidemics-in particular of measles infections-in large population centres. The second example is a compartmental model of a three-species food chain, where sudden population disappearances can be observed due to transient chaos. Our analysis lends support to the plausibility of chaos in population dynamics. However, for decreasing population size (increasing fluctuations) the distinction between chaos and stochasticity becomes more and more problematic. The interplay between deterministic dynamics and stochastic fluctuations, e.g. due to the integer structure of populations or a noisy environment, suggests an analysis combining methods from the theory of nonlinear dynamical systems as well as stochastic processes.