Data from: High temporal variability in the occurrence of consumer–resource interactions in ecological networks

Ecological networks have been used to represent interactions between species as fixed linkages despite that populations naturally oscillate over time and space. As such, the influence of the persistence of linkages between species in communities has been overlooked. Unfortunately, empirical analysis of the temporal variation of trophic networks is constrained by the lack of data with high spatial, temporal and taxonomic resolution. Here, we evaluate the spatiotemporal variability of multiple consumer-resource interactions to quantify the relative dominance of highly persistent versus poorly persistent interactions, the commonness of the interaction persistence patterns, and the effect of biotic and abiotic conditions on these patterns. We took advantage of a dataset from four large marine intertidal rocky-shore networks monitored seasonally for three years along 1000 km of the coast of northern Chile. Our results showed that the communities were characterized by few persistent interactions and a large number of transient trophic interactions, which was well described by a common exponential decay in the rank-frequency relationship of consumer–resource interactions despite dissimilarities in environmental conditions among sites. These results were independent of the degree of consumer–resource co-occurrence. Our results stress the need for more long-term studies that evaluate the temporal variability of ecological networks.

尽管种群在时间与空间尺度上天然存在波动，但生态网络（Ecological networks）常被用于将物种种间相互作用表征为固定联结关系。由此，群落内物种种间联结的持久性所产生的影响长期被忽视。遗憾的是，针对营养网络（trophic networks）时间变异的实证分析，受限于缺乏兼具高空间分辨率、高时间分辨率与高分类学分辨率的数据。本研究针对多种消费者-资源相互作用（consumer-resource interactions）的时空变异性展开评估，旨在量化高持久性相互作用与低持久性相互作用的相对优势占比、相互作用持久性模式的普遍性，以及生物与非生物条件对这些模式的影响。本研究依托智利北部1000公里海岸带内、经三年季节监测的四个大型海洋潮间带岩岸网络数据集展开分析。研究结果显示，群落以少量持久性相互作用与大量暂时性营养相互作用为特征；尽管各监测位点的环境条件存在差异，但消费者-资源相互作用的秩频关系普遍符合指数衰减规律，可很好地拟合这一特征。该结果与消费者-资源共现程度无关。本研究结果强调，亟需开展更多评估生态网络时间变异性的长期研究。