Krivan Vlastimil, Eisner Jan
Department of Theoretical Ecology, Institute of Entomology, Biology Centre, Academy of Sciences of the Czech Republic, Branisovská 31, Ceské Budejovice, Czech Republic.
Theor Popul Biol. 2006 Dec;70(4):421-30. doi: 10.1016/j.tpb.2006.07.004. Epub 2006 Jul 22.
This article analyzes the classical 2-resource-1-consumer apparent competition community module with the Holling type II functional response. Two types of resource regulation (top-down vs. combined top-down and bottom-up) and two types of consumer behaviors (inflexible consumers with fixed preferences for resources vs. adaptive consumers) are considered. When resources grow exponentially and consumers are inflexible foragers, one resource is always outcompeted due to strong apparent competition. Density dependent resource growth relaxes apparent competition so that resources can coexist. As multiple attractors (either equilibria or limit cycles) coexist, population dynamics and community composition depend on initial population densities. Population dynamics change dramatically when consumers forage adaptively. In this case, the results both for top-down, and combined top-down and bottom-up regulation are similar and they show that species persistence occurs for a much larger set of parameter values when compared with inflexible consumers. Moreover, population dynamics will be chaotic when resource carrying capacities are high enough. This shows that adaptive consumer switching can destabilize population dynamics.
本文分析了具有Holling II型功能反应的经典两资源-一消费者表观竞争群落模块。考虑了两种资源调节类型（自上而下与自上而下和自下而上相结合）以及两种消费者行为类型（对资源具有固定偏好的不灵活消费者与适应性消费者）。当资源呈指数增长且消费者是不灵活的觅食者时，由于强烈的表观竞争，一种资源总是会被淘汰。密度依赖的资源增长缓解了表观竞争，从而使资源能够共存。由于多个吸引子（平衡点或极限环）共存，种群动态和群落组成取决于初始种群密度。当消费者进行适应性觅食时，种群动态会发生巨大变化。在这种情况下，自上而下以及自上而下和自下而上相结合调节的结果相似，并且它们表明，与不灵活的消费者相比，在更大的一组参数值下会出现物种持续存在的情况。此外，当资源承载能力足够高时，种群动态将是混沌的。这表明适应性消费者切换会使种群动态不稳定。
