Pascual Mercedes, Guichard Frédéric
Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109-1048, USA.
Trends Ecol Evol. 2005 Feb;20(2):88-95. doi: 10.1016/j.tree.2004.11.012. Epub 2004 Dec 2.
Classical criticality describes sudden changes in the state of a system when underlying processes change slightly. At this transition, patchiness develops which lacks a characteristic or dominant spatial scale. Thus, criticality lies at the interface of two important subjects in ecology, threshold behavior and patchiness. Most ecological examples of criticality involve processes of disturbance and recovery; the spatial and temporal scales of these processes enable three different types of critical system to be distinguished: classical phase transitions, self organized criticality (SOC) and 'robust' criticality. Here, we review the properties defining these three types and their implications for threshold behavior and large intermittent temporal fluctuations, with examples taken from spatial stochastic models for predator-prey, infected-susceptible, and disturbance-recovery interactions. In critical systems, spatial properties of patchiness alone are insufficient indicators of impending sudden changes, unless complemented by the spatial and temporal scales of disturbance and recovery themselves.
经典临界性描述的是当基础过程稍有变化时系统状态的突然改变。在这种转变过程中，会出现缺乏特征性或主导空间尺度的斑块化现象。因此，临界性处于生态学中两个重要主题的交叉点，即阈值行为和斑块化。临界性在生态学中的大多数例子都涉及干扰和恢复过程；这些过程的时空尺度使得能够区分三种不同类型的临界系统：经典相变、自组织临界性（SOC）和“稳健”临界性。在此，我们回顾定义这三种类型的特性及其对阈值行为和大的间歇性时间波动的影响，并举例说明捕食者 - 猎物、感染 - 易感以及干扰 - 恢复相互作用的空间随机模型。在临界系统中，仅斑块化的空间特性不足以作为即将发生突然变化的指标，除非辅以干扰和恢复自身的时空尺度。
