Hastings Alan
Department of Environmental Science and Policy, University of California, One Shields Avenue, Davis, CA 95616, USA.
Science. 2003 Sep 12;301(5639):1525-6. doi: 10.1126/science.1087570.
Simple metapopulation models with random disturbances are used in species conservation or management, relying on the condition for persistence that the per-patch colonization rate be greater than the per-patch extinction rate. For a general model incorporating the role of succession or patch age-dependent extinction, I show that persistence requires the per-patch colonization rate to be greater than the inverse of mean patch age, where age is the time since the patch became available for colonization. Because mean patch age can be arbitrarily large relative to the extinction rate, currently persisting metapopulations may be persisting despite small colonization rates, and management approaches that do not consider the role of mean patch age may unnecessarily doom populations to extinction.
具有随机干扰的简单集合种群模型被用于物种保护或管理，其依据的持续存在条件是每个斑块的定殖率大于每个斑块的灭绝率。对于一个纳入演替作用或斑块年龄依赖性灭绝的一般模型，我表明持续存在要求每个斑块的定殖率大于平均斑块年龄的倒数，这里的年龄是指斑块可供定殖以来的时间。由于相对于灭绝率而言平均斑块年龄可能任意大，当前持续存在的集合种群可能尽管定殖率低仍能持续存在，而不考虑平均斑块年龄作用的管理方法可能会不必要地使种群走向灭绝。
