Continuous assembly required: Perpetual species turnover in two‐trophic‐level ecosystems
Continuous assembly required: Perpetual species turnover in two‐trophic‐level ecosystems
复制标题
需要连续组装：两级营养级生态系统中物种的永久更替
DOI：
10.1002/ecs2.4614
复制
发表时间：
2023
期刊：
影响因子：
2.7
通讯作者：
Ellner, Stephen P.
中科院分区：
文献类型：
--
作者：
Spaak, Jurg W.;Adler, Peter B.;Ellner, Stephen P.
社区集会通常被视为确定性的，汇聚在一个或最多几个可能的稳定端点上。然而，在自然界中，我们通常观察到群落组成的持续变化，这通常被归因于环境变化。但群落组成的持续变化也可能出现在确定性的、时不变的群落模型中，特别是食物网模型。我们的目标是确定为什么有些型号可以生产连续装配，而其他型号则不能。我们研究了一个简单的两营养级群落模型，表明持续的聚集是由营养级的相对生态位宽度驱动的。如果捕食者的生态位宽度大于猎物，群落聚集就会收敛到稳定的平衡。相反，如果捕食者的生态位宽度小于猎物，那么群落组成就永远不会稳定。食物网不需要达到稳定平衡的证据具有重要意义，因为许多基于平衡的群落生态学生态学理论可能很难适用于这种食物网。
Community assembly is often treated as deterministic, converging on one or at most a few possible stable endpoints. However, in nature, we typically observe continuous change in community composition, which is often ascribed to environmental change. But continuous changes in community composition can also arise in deterministic, time‐invariant community models, especially food web models. Our goal was to determine why some models produce continuous assembly and others do not. We investigated a simple two‐trophic‐level community model to show that continuous assembly is driven by the relative niche width of the trophic levels. If predators have a larger niche width than prey, community assembly converges to a stable equilibrium. Conversely, if predators have a smaller niche width than prey, then community composition never stabilizes. Evidence that food webs need not reach a stable equilibrium has important implications, as many ecological theories of community ecology based on equilibria may be difficult to apply to such food webs.