Johnson M P
School of Biological Sciences, Division of Biodiversity and Ecology, University of Southampton,UK.
Proc Biol Sci. 2000 Oct 7;267(1456):1967-72. doi: 10.1098/rspb.2000.1237.
Habitats may have dynamics that exist independently of the population densities of species occupying the habitat. For example, ephemeral habitat patches may disappear regardless of whether a particular species is present or not. Such habitat dynamics are frequently modelled by ignoring age-related variation in patch turnover rates. This can be thought of as a temporally implicit approach. An alternative, temporally explicit approach involves using age-structured models in order to describe variations in habitat dynamics. Simple models of coexistence between competing species show that temporally implicit models may be misleading where there is age-related variation in patch dynamics. Changing the shape of the patch survivorship function but not the average patch survivorship can result in mutual extinction, monocultures or coexistence of an inferior and a superior competitor. An explicit treatment of habitat demography may therefore offer improved predictive models and alternative landscape management strategies.
栖息地可能具有一些动态变化，这些变化独立于占据该栖息地的物种的种群密度而存在。例如，临时性的栖息地斑块可能会消失，无论特定物种是否存在。此类栖息地动态变化通常通过忽略斑块周转率中与年龄相关的变化来建模。这可以被视为一种时间上隐含的方法。另一种时间上明确的方法是使用年龄结构模型来描述栖息地动态变化中的差异。竞争物种之间共存的简单模型表明，在斑块动态变化存在与年龄相关差异的情况下，时间上隐含的模型可能会产生误导。改变斑块存活函数的形状但不改变平均斑块存活率，可能会导致相互灭绝、单一栽培或劣势与优势竞争者共存。因此，对栖息地种群统计学进行明确处理可能会提供改进的预测模型和替代性的景观管理策略。
