掠食者介导的明显竞争 II 的影响和生物学后果: PDE 模型
Yuan Lou1, Weirun Tao2, Zhi-An Wang3
1School of Mathematical Sciences, Shanghai Jiao Tong University, Shanghai, 200240, China.
Journal of mathematical biology
|October 13, 2025
概括
扩散和猎物出租车等空间运动可以在两种猎物物种的捕食者-猎物系统中创建复杂的模式. 这些运动可能会破坏种群的稳定,导致本地猎物被淘汰,与只有一个猎物物种的系统不同.
科学领域:
- 数学生物学 数学生物学
- 生态生态学 生态生态学
- 人口动态 人口动态
背景情况:
- 捕食者介导的明显竞争涉及一个共同的捕食者影响两个猎物物种之间的相互作用.
- 之前的工作 (Lou等人) 使用普通微分方程 (ODEs) 来建模这种没有空间动态的竞争.
- 了解空间效应对于全面了解生态相互作用至关重要.
研究的目的:
- 调查空间运动 (扩散和猎物出行) 对掠食者-猎物动态与明显竞争的影响.
- 分析这些空间因素如何影响一个掠食者,两个猎物系统中的人口稳定性和模式形成.
- 为了比较两个猎物系统中的空间效应与一个猎物系统中的空间效应.
主要方法:
- 扩展了一个时间ODE模型,包括空间扩散和猎物出租.
- 分析了解决方案的全局局限性和稳定状态的稳定性,在一个有纽曼边界条件的局限域中.
- 采用线性稳定性分析和数值模拟来研究分叉和模式形成.
主要成果:
- 在某些参数制度中发现了稳定状态的全球稳定性,值动态取决于捕食者死亡率.
- 在稳定制度之外,扩散和/或猎物税率可以通过稳定状态和Hopf分叉引发不稳定性.
- 出现了各种空间模式,包括聚合,均的周期性模式和不均的振荡模式.
结论:
- 在多猎物系统中,空间运动显著改变了种群动态,与单猎物系统不同.
- 扩散和猎物税率可以产生复杂的空间模式并影响系统的稳定性.
- 猎物出租车可以发挥双重作用 (稳定/破坏稳定),并可能在明显的竞争中促进本地猎物的消除.
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