Department of Environmental Biology, Sapienza University of Rome, Via dei Sardi 70, 00185, Rome, Italy.
National Inter-University Consortium for Marine Sciences (CoNISMa), Piazzale Flaminio 9, 00196, Rome, Italy.
Sci Rep. 2019 Dec 18;9(1):19331. doi: 10.1038/s41598-019-55960-8.
A central issue in ecology is understanding how complex and biodiverse food webs persist in the face of disturbance, and which structural properties affect disturbance propagation among species. However, our comprehension of assemblage mechanisms and disturbance propagation in food webs is limited by the multitude of stressors affecting ecosystems, impairing ecosystem management. By analysing directional food web components connecting species along food chains, we show that increasing species richness and constant feeding linkage density promote the establishment of predictable food web structures, in which the proportion of species co-present in one or more food chains is lower than what would be expected by chance. This reduces the intrinsic vulnerability of real food webs to disturbance propagation in comparison to random webs, and suggests that biodiversity conservation efforts should also increase the potential of ecological communities to buffer top-down and bottom-up disturbance in ecosystems. The food web patterns observed here have not been noticed before, and could also be explored in non-natural networks.
生态学中的一个核心问题是理解在面临干扰时，复杂且生物多样性丰富的食物网是如何持续存在的，以及哪些结构特性会影响物种间的干扰传播。然而，由于影响生态系统的胁迫因素众多，我们对食物网中集合机制和干扰传播的理解受到了限制，从而影响了生态系统的管理。通过分析沿食物链连接物种的有向食物网成分，我们表明，增加物种丰富度和恒定的摄食连接密度会促进可预测的食物网结构的建立，在这种结构中，一种或多种食物链中共存的物种比例低于随机情况下的预期比例。这降低了真实食物网相对于随机网络对干扰传播的内在脆弱性，并表明生物多样性保护工作还应提高生态群落缓冲生态系统自上而下和自下而上干扰的潜力。这里观察到的食物网模式以前没有被注意到，也可以在非自然网络中进行探索。
