发表机构
Ramakrishna Mission Vivekananda Educational and Research Institute; Sorbonne Université, CNRS, Laboratoire Jacques-Louis Lions (LJLL)（罗摩克里希那传教士维韦卡南达教育与研究机构; 索邦大学，法国国家科学研究中心，雅克-路易·利翁斯实验室）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究通过反应扩散模型分析额外食物下捕食者自我竞争对捕食-被捕食系统斑图形成的影响，发现竞争强度与猎物扩散决定振荡或固定斑图，为生物防治提供理论指导。
AI 中文摘要
向释放的捕食者提供额外的、不繁殖的食物是增强型生物防治中的标准手段，但已知其缺点在于，由于没有限制捕食者自身数量的因素，额外的食物会使其种群无限制地增长。捕食者之间的竞争提供了缺失的制动机制。这种自我限制如何重塑两个物种的空间布局，此前尚未被探究。我们通过一个反应扩散模型来研究这一问题，该模型包含逻辑增长的猎物和具有Holling II型功能反应、同时利用额外食物并以强度进行竞争的捕食者。在充分混合的背景下，我们精确地定位了共存态的Hopf分岔，并证明了由此产生的极限环是稳定的，因此弱竞争会导致繁荣-萧条振荡，而非失控增长。允许空间运动后，我们得到了扩散驱动的Turing阈值，在该阈值下均匀态破裂为高密度和低密度的静止斑块，并发现均匀振荡在出现时是稳定的。以猎物移动性和竞争强度作为控制参数，斑图形成不稳定性与振荡不稳定性在单一点相遇，我们计算了该点的动力学。模拟证实了以下序列：弱竞争产生全场振荡，更强的竞争与更快的猎物扩散产生固定斑图，而在交叉点附近，两者结合形成随时间脉动的斑图。因此，捕食者的自我竞争决定了群落的空间结构，而这正是当额外食物被用于在野外引导防治因子时所重要的。
英文摘要
Supplying a released predator with additional, non reproducing food is a standard lever in augmentative biological control, with a known drawback with nothing limiting the predators own numbers, the extra food lets its population grow without bound. Competition among the predators supplies the missing brake. Howthis self limitation reshapes the spatial arrangement of the two species has not been asked. We address it with a reaction diffusion model of a logistically growing prey and a predator feeding through a Holling type II response that also draws on additional food , the predators competing among themselves at strength. In the well mixed setting we locate the Hopf bifurcation of the coexistence state exactly and show the cycle born there is stable, so weak competition gives boom bust oscillations, not runaway growth. Allowing movement, we obtain the diffusion driven Turing threshold at which the uniform state breaks into stationary patches of high and low density, and find the uniform oscillation stable as it appears. With prey mobility and competition strength as control parameters, the pattern forming and oscillatory instabilities meet at a single point, where we compute the dynamics. Simulations confirm the sequence weak competition gives a wholefield oscillation, stronger competition with faster prey spread gives fixed patterns, and near the crossover the two combine into patterns that pulse in time. Predator self competition therefore sets the spatial structure of the community, which is what matters when additional food is used to steer a control agent in the field.
Comments24 pages, 9 figures
