Department of Mathematics, University of Linkoping, 58183 Linkoping, Sweden.
Institute for Mechanical Engineering Problems, Russian Academy of Sciences, Saint Petersburg, Russia and Saint Petersburg National Research University of Information Technologies, Mechanics and Optics, Saint Petersburg, Russia.
Phys Rev E. 2017 Mar;95(3-1):032413. doi: 10.1103/PhysRevE.95.032413. Epub 2017 Mar 21.
We investigate the formation of stable ecological networks where many species share the same resource. We show that such a stable ecosystem naturally occurs as a result of extinctions. We obtain an analytical relation for the number of coexisting species, and we find a relation describing how many species that may become extinct as a result of a sharp environmental change. We introduce a special parameter that is a combination of species traits and resource characteristics used in the model formulation. This parameter describes the pressure on the system to converge, by extinctions. When that stress parameter is large, we obtain that the species traits are concentrated at certain values. This stress parameter is thereby a parameter that determines the level of final biodiversity of the system. Moreover, we show that the dynamics of this limit system can be described by simple differential equations.
我们研究了在许多物种共享同一资源的情况下形成稳定生态网络的过程。我们表明，这种稳定的生态系统是由于灭绝而自然产生的。我们得到了共存物种数量的解析关系，并发现了一个描述由于环境急剧变化而可能灭绝的物种数量的关系。我们引入了一个特殊参数，它是模型公式中物种特征和资源特征的组合。该参数描述了通过灭绝使系统收敛的压力。当该压力参数较大时，我们发现物种特征集中在某些值上。因此，这个压力参数是决定系统最终生物多样性水平的一个参数。此外，我们还表明，这个极限系统的动态可以用简单的微分方程来描述。
