Species loss is a global issue. With up to a million species at risk and insufficient protected area to maintain the world's biodiversity, humanity will increasingly need to rely on species re‐introductions to locally restore diversity and function. However, such restoration attempts are bound to fail when ecological communities get locked in a closed state that is resistant to recovery. It is presently unknown how to repair these closed systems. We use mathematical models to identify ways out of this problem. We first show how ecological communities may enter a closed state, to then explain how to open them up again for restoration of their original diversity. We find that restoration is often still possible shortly after initial species loss, as (1) the secondary extinctions that produce closure have not happened yet and (2) mild population fluctuations still allow successful repair during a transient postdisturbance phase. However, after this typically short window of opportunity for restoration, the system enters a new equilibrium, which may be a closed state. Our analysis shows how to take ecological communities out of the closed state: Appropriate management of carrying capacities produces a regime of mild population fluctuations that opens a window for successful species re‐introductions. These windows can be perpetually recurring or permanently open. Such opportunities for repair can be absent under regimes of wild cycles or perfect stability. We conclude that mild cycles may open windows of opportunity for the repair of communities that have become resistant to recovery.

中文翻译：

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温和的周期使封闭的社区得以生态恢复

物种损失是一个全球性问题。由于多达一百万种物种处于危险之中，保护区不足以维持世界的生物多样性，人类将越来越需要依靠重新引入物种来在当地恢复多样性和功能。但是，当生态群落被锁定在无法恢复的封闭状态时，这种恢复尝试必将失败。目前未知如何维修这些封闭系统。我们使用数学模型来确定解决此问题的方法。我们首先展示生态社区如何进入封闭状态，然后说明如何再次开放生态社区以恢复其原始多样性。我们发现，最初物种消失后不久，恢复仍然很可能，因为（1）尚未发生造成闭合的继发性灭绝，以及（2）种群的轻微波动仍允许在短暂的扰动后阶段成功修复。但是，在恢复的机会通常很短之后，系统进入了新的平衡状态，该状态可能是封闭状态。我们的分析显示了如何使生态群落脱离封闭状态：适当地管理承载能力会产生种群温和波动的制度，从而为成功引入物种开辟了一个窗口。这些窗口可以永久重复出现或永久打开。在野外循环或完全稳定的情况下，可能没有这种修复机会。我们得出的结论是，温和的周期可能为修复已变得难以恢复的社区打开机会之窗。