Centre for Biodiversity Theory and Modelling, Experimental Ecology Station, Centre National de la Recherche Scientifique, 09200, Moulis, France.
Biol Rev Camb Philos Soc. 2013 May;88(2):365-79. doi: 10.1111/brv.12003. Epub 2012 Nov 30.
The paired source and sink concepts are used increasingly in ecology and Earth sciences, but they have evolved in divergent directions, hampering communication across disciplines. We propose a conceptual framework that unifies existing definitions, and review their most significant consequences for the various disciplines. A general definition of the source and sink concepts that transcends disciplines is based on net flows between the components of a system: a source is a subsystem that is a net exporter of some living or non-living entities of interest, and a sink is a net importer of these entities. Sources and sinks can further be classified as conditional and unconditional, depending on the intrinsic propensity of subsystems to either produce (source) or absorb (sink) a surplus of these entities under some (conditional) or all (unconditional) conditions. The distinction between conditional and unconditional sources and sinks, however, is strongly context dependent. Sources can turn into sinks, and vice versa, when the context is changed, when systems are subject to temporal fluctuations or evolution, or when they are considered at different spatial and temporal scales. The conservation of ecosystem services requires careful consideration of the source-sink dynamics of multiple ecosystem components. Our synthesis shows that source-sink dynamics has profound consequences for our ability to understand, predict, and manage species and ecosystems in heterogeneous landscapes.
对集源与汇的概念在生态学和地球科学领域的应用日益广泛，但这些概念在不同学科中已经朝着不同的方向发展，从而阻碍了学科间的交流。我们提出了一个统一现有定义的概念框架，并回顾了它们对各学科的最重要影响。超越学科的源和汇概念的一般定义是基于系统各组成部分之间的净流动：源是净输出某些感兴趣的生物或非生物实体的子系统，而汇是这些实体的净输入者。源和汇还可以根据子系统在某些（有条件的）或所有（无条件的）条件下产生（源）或吸收（汇）这些实体过剩的内在倾向进一步分类为有条件的和无条件的。然而，有条件和无条件源和汇之间的区别强烈依赖于上下文。当上下文发生变化、系统受到时间波动或进化的影响，或者当它们在不同的时空尺度上被考虑时，源可以转变为汇，反之亦然。生态系统服务的保护需要仔细考虑多个生态系统组成部分的源汇动态。我们的综合研究表明，源汇动态对我们理解、预测和管理异质景观中的物种和生态系统的能力有着深远的影响。
