Geomorphic Complexity as a Disturbance Modifier

目前的理论认为，生态系统的稳定性是一个功能， 物理和生物的复杂性。 频繁的干扰可能 减少这种复杂性，从而破坏生态系统的稳定， 它们更容易受到未来扰动的影响。 理论预测 具有大规模物理（即地貌）的生态系统 复杂性可以有效地保持结构的完整性， 受到灾难性的干扰。 该项目将开发 一个将生态系统结构变化联系起来的定量模型 从干扰到稳定的复杂性。 因为 河流受景观地貌的影响很大， 对干扰的反应相对较快，河流生态系统 将用于 扰动-稳定关系 从伐木影响、山体滑坡和洪水等方面评估， 一般河流生态系统动态，特别强调鱼类 人口反应。 为了解决大型和 小规模的物理复杂性，模型将分层 结构化（即包含流域、河段和河道单元 规模），并侧重于审查伐木对 河流达到规模。 假设开发和评估与此 模型应该提供新的见解，地貌复杂性如何 与结构化生态系统的干扰相互作用， 生物成分成功或失败的阶段。

Current theory suggests that ecosystem stability is a function of physical and biological complexity. Frequent disturbances may reduce this complexity and thereby destabilize ecosystems, making them more susceptible to future perturbations. Theory predicts that ecosystems with large scale physical (i.e. geomorphic) complexity can effectively maintain structural integrity when impacted by catastrophic disturbances. This project will develop a quantitative model that links changes in ecosystem structural complexity resulting from disturbances, to stability. Because streams are strongly influenced by landscape geomorphology and respond relatively quickly to disturbances, stream ecosystems will be used. Disturbance-stability relationships will be assessed in terms of logging impacts, landslides, and floods on general stream ecosystem dynamics, with special emphasis on fish population responses. To address the importance of large and small scale physical complexity, the model will be hierarchically structured (i.e. contain basin, stream reach, and channel unit scales), and focus on examination of logging impacts at the stream reach scale. Hypotheses developed and evaluated with this model should provide new insights into how geomorphic complexity interacts with disturbance to structure ecosystems and set the stage for the success or failure of biotic components.