Bastolla Ugo, Lässig Michael, Manrubia Susanna C, Valleriani Angelo
Centro de Astrobiología, INTA-CSIC, Ctra. de Ajalvir km. 4, 28850 Torrejón de Ardoz, Madrid, Spain.
J Theor Biol. 2005 Aug 21;235(4):521-30. doi: 10.1016/j.jtbi.2005.02.005. Epub 2005 Mar 31.
This is the first of two papers where we discuss the limits imposed by competition to the biodiversity of species communities. In this first paper, we study the coexistence of competing species at the fixed point of population dynamic equations. For many simple models, this imposes a limit on the width of the productivity distribution, which is more severe the more diverse the ecosystem is (1994, Theor. Popul. Biol. 45, 227-276). Here we review and generalize this analysis, beyond the "mean-field"-like approximation of the competition matrix used in previous works, and extend it to structured food webs. In all cases analysed, we obtain qualitatively similar relations between biodiversity and competition: the narrower the productivity distribution is, the more species can stably coexist. We discuss how this result, considered together with environmental fluctuations, limits the maximal biodiversity that a trophic level can host.
这是两篇论文中的第一篇，我们将在其中讨论竞争对物种群落生物多样性所施加的限制。在这第一篇论文中，我们研究了竞争物种在种群动态方程的固定点处的共存情况。对于许多简单模型而言，这对生产力分布的宽度施加了限制，生态系统越多样化，这种限制就越严格（1994年，《理论种群生物学》45卷，227 - 276页）。在此，我们回顾并推广这一分析，超越先前工作中使用的竞争矩阵的“平均场”式近似，并将其扩展到结构化食物网。在所有分析的案例中，我们在生物多样性与竞争之间获得了定性相似的关系：生产力分布越窄，能够稳定共存的物种就越多。我们讨论了这一结果与环境波动一起如何限制一个营养级所能承载的最大生物多样性。
