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arXiv 1501.04497q-bio.PE
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食物网〈动〉组装规则

Food web assembly rules

Jan O. Haerter, Namiko Mitarai, Kim Sneppen

摘要:

在食物网中,许多相互作用的物种共存,尽管竞争排斥原则和明显的竞争所施加的限制。对于广义的Lotka-Volterra方程,可持续共存需要相互作用矩阵的非零行列式。在这里,我们表明,这一要求相当于要求每个物种是一个非重叠配对的一部分,这在很大程度上限制了食物网〈动〉<动>结构。我们证明,一个稳定的食物网〈动〉<动>,总是可以得到,如果存在一个非重叠配对。如果不是,矩阵秩可以用来量化生态位的缺乏,对应于未配对的物种。对于每个营养级的物种丰富度,我们推导出了食物网〈动〉<动>的装配规则,它指定了可持续的组合。在相邻的层次中,这些规则允许较高层次避免较低层次的竞争排斥,从而纳入明显的竞争。在协议的数据,组装规则预测高的物种数量在中间水平和变薄的顶部和底部。利用全面食物网〈动〉<动>数据,我们展示了杂食动物或寄生虫与宿主在多个营养级可以放松限制,并帮助获得共存的食物网。因此,杂食动物可能是保持社区完整的胶水,即使在物种灭绝或生态释放的情况下。

英文摘要:

In food webs, many interacting species coexist despite the restrictions imposed by the competitive exclusion principle and apparent competition. For the generalized Lotka-Volterra equations, sustainable coexistence necessitates nonzero determinant of the interaction matrix. Here we show that this requirement is equivalent to demanding that each species be part of a non-overlapping pairing, which substantially constrains the food web structure. We demonstrate that a stable food web can always be obtained if a non-overlapping pairing exists. If it does not, the matrix rank can be used to quantify the lack of niches, corresponding to unpaired species. For the species richness at each trophic level, we derive the food web assembly rules, which specify sustainable combinations. In neighboring levels, these rules allow the higher level to avert competitive exclusion at the lower, thereby incorporating apparent competition. In agreement with data, the assembly rules predict high species numbers at intermediate levels and thinning at the top and bottom. Using comprehensive food web data, we demonstrate how omnivores or parasites with hosts at multiple trophic levels can loosen the constraints and help obtain coexistence in food webs. Hence, omnivory may be the glue that keeps communities intact even under extinction or ecological release of species.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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