Department of Computing Science and Mathematics, University of Stirling, Stirling FK9 4LA, Scotland, United Kingdom.
Am Nat. 2010 Aug;176(2):149-58. doi: 10.1086/653669.
Increasing concerns about the changing environment and the emergence of pathogens that cross species boundaries have added to the urgency of understanding the dynamics of complex ecological systems infected by pathogens. Of particular interest is the often counterintuitive way in which infection and predation interact and the consequent difficulties in designing control strategies to manage the system. To understand the mechanisms involved, we focus on the pathogen exclusion problem, using control maps (on which the network of exclusion thresholds are plotted) in order to readily identify which exclusion strategies will work and why others will not. We apply this approach to the analysis of parasite exclusion in two game bird ecologies. For higher dimensions, we propose a computational scheme that will generate the optimal exclusion strategy, taking into account all operational constraints on the pathogen invasion matrix, populations, and controls. The situation is further complicated when external forcing distorts pathogen thresholds. This distortion is highly sensitive to the lags between forcing components, a sensitivity that can be exploited by management using correctly lagged cyclically varying controls to reduce the effort involved in pathogen exclusion.
人们越来越关注环境变化和跨越物种界限的病原体的出现，这使得人们更加迫切地需要了解受病原体感染的复杂生态系统的动态。特别有趣的是，感染和捕食相互作用的方式往往违反直觉，这给设计控制策略来管理系统带来了困难。为了理解所涉及的机制，我们关注病原体排除问题，使用控制图（其上绘制了排除阈值的网络）来方便地确定哪些排除策略将起作用，以及为什么其他策略不起作用。我们将这种方法应用于两种猎鸟生态系统中的寄生虫排除分析。对于更高的维度，我们提出了一种计算方案，该方案将考虑病原体入侵矩阵、种群和控制的所有操作限制，生成最佳排除策略。当外部强制力扭曲病原体阈值时，情况会变得更加复杂。这种扭曲对强制力分量之间的滞后非常敏感，管理部门可以利用滞后的周期性变化控制来减少排除病原体所需的工作量，从而利用这种敏感性。
