论文标题
具有分层互动的广义Lotka-Volterra模型
Generalised Lotka-Volterra model with hierarchical interactions
论文作者
论文摘要
在对复杂生态系统的分析中，通常使用随机相互作用系数，通常认为所有物种在统计上都是等效的。在这项工作中，我们通过根据级联模型选择相互作用来放松这一假设，我们将其纳入了广义的Lotka-Volterra动力系统中。这些互动在社区中施加了层次结构。平均而言，从层次结构中，与在层次结构下的物种相互作用的平均而言，而不是与上面的物种相互作用。使用动态平均场理论，我们证明了强大的层次结构正在稳定，但是它减少了幸存社区中的物种数量以及它们的丰富性。此外，我们表明，在层次结构中跨位置的相互作用系数方差中的异质性增加是不稳定的。我们还对幸存社区的结构发表评论，并证明物种生存的丰度和可能性取决于其在层次结构中的地位。
In the analysis of complex ecosystems it is common to use random interaction coefficients, often assumed to be such that all species are statistically equivalent. In this work we relax this assumption by choosing interactions according to the cascade model, which we incorporate into a generalised Lotka-Volterra dynamical system. These interactions impose a hierarchy in the community. Species benefit more, on average, from interactions with species further below them in the hierarchy than from interactions with those above. Using dynamic mean-field theory, we demonstrate that a strong hierarchical structure is stabilising, but that it reduces the number of species in the surviving community, as well as their abundances. Additionally, we show that increased heterogeneity in the variances of the interaction coefficients across positions in the hierarchy is destabilising. We also comment on the structure of the surviving community and demonstrate that the abundance and probability of survival of a species is dependent on its position in the hierarchy.
