Bashkirtseva Irina, Ryashko Lev, Ryazanova Tatyana
Ural Federal University, Yekaterinburg, Russia.
Math Biosci. 2017 Nov;293:38-45. doi: 10.1016/j.mbs.2017.08.007. Epub 2017 Aug 26.
Motivated by important ecological applications we study how noise can reduce a number of trophic levels in hierarchically related multidimensional population systems. A nonlinear model with three trophic levels under the influence of external stochastic forcing is considered as a basic conceptual example. We analyze a probabilistic mechanism of noise-induced extinction of separate populations in this "prey-predator-top predator" system. We propose a new general mathematical approach for the estimation of the proximity of equilibrium regimes of this stochastic model to hazardous borders where abrupt changes in dynamics of ecological systems can occur. Our method is based on the stochastic sensitivity function technique and visualization method of confidence domains. Constructive abilities of this mathematical approach are demonstrated in the analysis of different scenaria of noise-induced reducing of the number of trophic levels.
受重要生态应用的推动，我们研究噪声如何减少层次相关的多维种群系统中的营养级数量。一个受外部随机强迫影响的具有三个营养级的非线性模型被视为一个基本概念示例。我们分析了这个“猎物-捕食者-顶级捕食者”系统中噪声诱导的单个种群灭绝的概率机制。我们提出了一种新的通用数学方法，用于估计该随机模型的平衡态与危险边界的接近程度，在危险边界处生态系统动态可能会发生突然变化。我们的方法基于随机灵敏度函数技术和置信域可视化方法。这种数学方法的建设性能力在分析噪声诱导营养级数量减少的不同情景中得到了证明。
