In this paper, we derive a simple model for the description of an ecological system including several subgroups with distinct ages, in order to analyze the influence of various phenomena on temporal evolution of the considered species. Our aim is to address the question of resilience of the global system, defined as its ability to stabilize itself to equilibrium, when being perturbed by exterior fluctuations. It is shown that a under a critical condition involving growth rate and mortality rate of each subgroup, extinction of all species may occur.

中文翻译：

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用于研究树木种群的年龄组模型

在本文中，我们推导出一个简单的模型来描述一个生态系统，包括几个具有不同年龄的亚群，以分析各种现象对所考虑物种的时间演化的影响。我们的目标是解决全球系统的弹性问题，定义为在受到外部波动干扰时，其自身稳定到平衡的能力。结果表明，在涉及各亚群增长率和死亡率的临界条件下，可能发生所有物种的灭绝。