Diversity increases the stability of ecosystems
Diversity increases the stability of ecosystems
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多样性增加了生态系统的稳定性
DOI：
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发表时间：
2020
期刊：
影响因子：
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通讯作者：
H. Makse
中科院分区：
文献类型：
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作者：
Francesca Arese Lucini;F. Morone;M. Tomassone;H. Makse
1972年，罗伯特·梅（Robert May）指出，多样性对生态系统是有害的，因为随着物种数量的增加，生态系统会变得不稳定。这就是所谓的多样性-稳定性悖论，它是通过考虑物种之间线性相互作用的数学模型推导出来的。尽管与经验证据相矛盾，但多样性-稳定性悖论经受住了40多年的时间考验。在本文中，我们首先表明，这个悖论是一个结论，完全由在其推导中所采用的模型的线性驱动，它允许在稳定性分析中忽略不动点解。线性模型导致了一个不适定的解，并伴随着它的矛盾的稳定性预测。然后，我们考虑了一个物种间非线性相互作用的模型生态系统，当物种数量增加时，生态系统会趋于稳定。物种相互作用中的饱和非线性项类似于出现在基因调控、神经元、信息扩散和生态系统等系统中的希尔函数。该模型的精确不动点解基于k核渗透，并表明悖论消失。这一理论结果准确且无扰动，表明多样性对生态系统有益，与分析的实验证据一致
In 1972, Robert May showed that diversity is detrimental to an ecosystem since, as the number of species increases, the ecosystem is less stable. This is the so-called diversity-stability paradox, which has been derived by considering a mathematical model with linear interactions between the species. Despite being in contradiction with empirical evidence, the diversity-stability paradox has survived the test of time for over 40+ years. In this paper we first show that this paradox is a conclusion driven solely by the linearity of the model employed in its derivation which allows for the neglection of the fixed point solution in the stability analysis. The linear model leads to an ill-posed solution and along with it, its paradoxical stability predictions. We then consider a model ecosystem with nonlinear interactions between species, which leads to a stable ecosystem when the number of species is increased. The saturating non linear term in the species interaction is analogous to a Hill function appearing in systems like gene regulation, neurons, diffusion of information and ecosystems The exact fixed point solution of this model is based on k-core percolation and shows that the paradox disappears. This theoretical result, which is exact and non-perturbative, shows that diversity is beneficial to the ecosystem in agreement with analyzed experimental evidence