Paula Dias is at Centre d'Ecologie Fonctionnelle et Evolutive, CNRS, BP 5051, F-34033 Montpellier cedex 1, France.
Trends Ecol Evol. 1996 Aug;11(8):326-30. doi: 10.1016/0169-5347(96)10037-9.
The various habitats inhabited by a given species are never of the same quality. When demographic models take into account this habitat heterogeneity, the source-sink concept naturally emerges: a local demographic surplus arises in good quality habitats (source), and a local demographic deficit occurs in habitats of poor quality (sink). Within a landscape, a permanent migration of propagules or individuals from source to sink habitats may lead to a stabilization of the overall demographic system. This simple situation, explored in the recent literature, has surprising properties. In particular, it requires a change in our view of classical concepts such as ecological niche and carrying capacity, it can explain the existence and persistence of local maladaptation and it can improve conservation practice.
给定物种所栖息的各种生境从未具有相同的质量。当人口模型考虑到这种生境异质性时，源-汇概念自然就出现了：在高质量生境中会出现局部人口过剩（源），而在低质量生境中则会出现局部人口不足（汇）。在景观中，从源到汇生境的繁殖体或个体的持续迁移可能会导致整个人口系统的稳定。这种在近期文献中探讨的简单情况具有惊人的特性。特别是，它要求我们改变对生态位和承载能力等经典概念的看法，它可以解释局部适应不良的存在和持续，并可以改进保护实践。
