Instituto de Biociências, Universidade Federal de Mato Grosso do Sul, Campo Grande, Brazil.
Laboratório de Estrutura e Dinâmica da Diversidade (LEDDiv), Departamento de Biologia Animal, Instituto de Biologia, Universidade Estadual de Campinas - UNICAMP, Campinas, Brazil.
Ecology. 2022 Aug;103(8):e3716. doi: 10.1002/ecy.3716. Epub 2022 May 19.
Space and time promote variation in network structure by affecting the likelihood of potential interactions. However, little is known about the relative roles of ecological and biogeographical processes in determining how species interactions vary across space and time. Here we study the spatiotemporal variation in predator-prey interaction networks formed by anurans and arthropods and test for the effects of prey availability in determining interaction patterns, information that is often absent and limits the understanding of the determinants of network structure. We found that network dissimilarity between ecoregions and seasons was high and primarily driven by interaction rewiring.We also found that species turnover was positively related to geographical distance. Using a null model approach to disentangle the effect of prey availability on the spatial and temporal variation, we show that differences in prey availability were important in determining the variation in network structure between seasons and among areas. Our study reveals that fluctuations in prey abundance, alongside the limited dispersal abilities of anurans and their prey, may be responsible for the spatial patterns that emerged in our predator-prey metaweb. These findings contribute to our understanding of the assembly rules that maintain biotic processes in metacommunities and highlight the importance of prey availability to the structure of these systems.
空间和时间通过影响潜在相互作用的可能性来促进网络结构的变异。然而，关于生态和生物地理过程在确定物种相互作用如何随空间和时间变化方面的相对作用，我们知之甚少。在这里，我们研究了由两栖动物和节肢动物形成的捕食者-猎物相互作用网络的时空变化，并检验了猎物丰度在确定相互作用模式方面的作用，而这些信息通常是缺失的，限制了我们对网络结构决定因素的理解。我们发现，生态区和季节之间的网络差异很大，主要是由相互作用的重新布线驱动的。我们还发现，物种周转率与地理距离呈正相关。我们使用一个零模型方法来区分猎物丰度对时空变化的影响，结果表明，猎物丰度的差异对于确定季节和区域之间网络结构的变化非常重要。我们的研究表明，猎物丰度的波动，以及两栖动物及其猎物有限的扩散能力，可能是导致我们的捕食者-猎物元网络中出现空间模式的原因。这些发现有助于我们理解维持生物群落中生物过程的组装规则，并强调了猎物丰度对这些系统结构的重要性。
