Ecological communities from random generalized Lotka-Volterra dynamics with nonlinear feedback.
Ecological communities from random generalized Lotka-Volterra dynamics with nonlinear feedback.
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DOI：
10.1103/physreve.101.032101
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发表时间：
2019-09
期刊：
影响因子：
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通讯作者：
Laura Sidhom;T. Galla
中科院分区：
文献类型：
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作者：
Laura Sidhom;T. Galla
研究了具有随机相互作用系数和非线性反馈的生态群落广义Lotka-Volterra动力学的结果。仿真结果表明，非线性反馈的饱和使动力学稳定。这在具有分段线性饱和响应的广义Lotka-Volterra方程的解析生成泛函方法中得到证实。对于这样的系统，我们能够推导出控制稳定不动点相位的自一致关系，并进行线性稳定性分析以预测不稳定行为的开始。我们详细研究了随机相互作用系数的均值、方差和协方差的联合效应，以及非线性响应的饱和值。我们发现，随着非线性反馈的引入，稳定性和多样性增加，其中降低饱和值与减小协方差具有相似的效果。我们还发现合作不再对非线性反馈的稳定性产生不利影响，并且在更强的饱和度下，序参数意味着丰度和多样性较少依赖于相互作用的对称性。
We investigate the outcome of generalized Lotka-Volterra dynamics of ecological communities with random interaction coefficients and nonlinear feedback. We show in simulations that the saturation of nonlinear feedback stabilizes the dynamics. This is confirmed in an analytical generating-functional approach to generalized Lotka-Volterra equations with piecewise linear saturating response. For such systems we are able to derive self-consistent relations governing the stable fixed-point phase and to carry out a linear stability analysis to predict the onset of unstable behavior. We investigate in detail the combined effects of the mean, variance, and covariance of the random interaction coefficients, and the saturation value of the nonlinear response. We find that stability and diversity increases with the introduction of nonlinear feedback, where decreasing the saturation value has a similar effect to decreasing the covariance. We also find cooperation to no longer have a detrimental effect on stability with nonlinear feedback, and the order parameters mean abundance and diversity to be less dependent on the symmetry of interactions with stronger saturation.