The identity of an ecological regime is central to modern resilience theory and our understanding of how systems collapse and reorganize following disturbance. However, resilience-based models used in ecosystem management have been criticized for their failure to integrate disturbance outcomes into regime identity. Assessments are needed to understand how well these classifications represent ecosystem responses that occur over management relevant time scales. We tracked post-wildfire forest and grassland dynamics 27 years after wildfire in eastern ponderosa pine savanna. We tested for differences between the assigned identity of a site (forest or grassland) versus classifications based on the site's disturbance history (burned/unburned and fire severity). Under current ecosystem models used to manage these forest-grassland ecotones, forests that experience high severity fire are expected to resemble an unburned grassland following fire, while forests and grasslands that experience low severity fire are expected to resemble unburned forests and grasslands, respectively. Twenty-seven years after wildfire, burned forests and grasslands displayed a high degree of departure from their expected regime identity. Plant and bird communities deviated significantly on sites that experienced low severity fire from undisturbed sites classified under the same ecological regime (grassland or forest). Forest sites that experienced high severity fire were the most unique of all disturbance history classes. Our results demonstrate that structures and communities predicted under resilience-based models used for eastern ponderosa pine management do not emerge over management relevant time scales following disturbance. Over 20% of variation in ecological structures and communities was explained by a single, 27-year-old disturbance. Integrating disturbance legacies will help improve applied models of ecosystem dynamics.

中文翻译：

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崩溃、重组和政权认同：打破林草交错带中过去的管理范式

生态系统的特性是现代复原力理论的核心，也是我们理解系统如何在扰动后崩溃和重组的核心。然而，用于生态系统管理的基于复原力的模型因未能将干扰结果纳入制度认同而受到批评。需要进行评估以了解这些分类在多大程度上代表了在管理相关时间尺度上发生的生态系统响应。我们追踪了东部黄松稀树草原野火发生 27 年后的野火后森林和草原动态。我们测试了场地（森林或草地）的指定身份与基于场地干扰历史（燃烧/未燃烧和火灾严重程度）的分类之间的差异。在目前用于管理这些林草交错带的生态系统模型下，预计经历高严重度火灾的森林类似于火灾后未燃烧的草原，而经历低严重度火灾的森林和草原预计分别类似于未燃烧的森林和草原。野火发生 27 年后，被烧毁的森林和草原表现出与其预期政权身份的高度背离。植物和鸟类群落在遭受低严重性火灾的地点与归类为同一生态制度（草地或森林）的未受干扰地点显着偏离。经历过严重火灾的森林遗址是所有扰乱历史类别中最独特的。我们的结果表明，在用于东部黄松管理的基于复原力的模型下预测的结构和社区不会在干扰后出现在管理相关的时间尺度上。生态结构和群落中超过 20% 的变化是由一次长达 27 年的扰动来解释的。整合干扰遗产将有助于改进生态系统动力学的应用模型。