{"title":"Food web complexity modulates environmental impacts on food chain length","authors":"Shota Shibasaki, Akira Terui","doi":"10.1111/oik.10331","DOIUrl":null,"url":null,"abstract":"The determinants of food chain length (FCL), a crucial aspect of biodiversity due to its effects on ecosystem functioning, have long been debated. Previous studies proposed resource availability, disturbance, and ecosystem size as environmental drivers. However, studies using stable isotope approaches have shown inconsistent results, indicating missing links between environmental drivers and FCL. Here, we hypothesized that species richness and motifs (i.e. three‐species subgraphs) modulated environmental effects on FCL. Combining empirical food webs with our <jats:italic>N</jats:italic>‐species food web model, we found that FCL disproportionately changed at low species richness, with saturation at high species richness. This functional response was essential to the interdependent effects of disturbance and ecosystem size in our model. Disturbance more strongly regulated FCL in smaller ecosystems, where species richness was low. Similarly, increasing ecosystem size enhanced FCL under strong, but not weak, disturbance regimes. Our study suggests that internal food web structure should deepen our understanding of how FCL changes over environments.","PeriodicalId":19496,"journal":{"name":"Oikos","volume":null,"pages":null},"PeriodicalIF":3.1000,"publicationDate":"2024-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Oikos","FirstCategoryId":"93","ListUrlMain":"https://doi.org/10.1111/oik.10331","RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ECOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
The determinants of food chain length (FCL), a crucial aspect of biodiversity due to its effects on ecosystem functioning, have long been debated. Previous studies proposed resource availability, disturbance, and ecosystem size as environmental drivers. However, studies using stable isotope approaches have shown inconsistent results, indicating missing links between environmental drivers and FCL. Here, we hypothesized that species richness and motifs (i.e. three‐species subgraphs) modulated environmental effects on FCL. Combining empirical food webs with our N‐species food web model, we found that FCL disproportionately changed at low species richness, with saturation at high species richness. This functional response was essential to the interdependent effects of disturbance and ecosystem size in our model. Disturbance more strongly regulated FCL in smaller ecosystems, where species richness was low. Similarly, increasing ecosystem size enhanced FCL under strong, but not weak, disturbance regimes. Our study suggests that internal food web structure should deepen our understanding of how FCL changes over environments.
期刊介绍:
Oikos publishes original and innovative research on all aspects of ecology, defined as organism-environment interactions at various spatiotemporal scales, so including macroecology and evolutionary ecology. Emphasis is on theoretical and empirical work aimed at generalization and synthesis across taxa, systems and ecological disciplines. Papers can contribute to new developments in ecology by reporting novel theory or critical empirical results, and "synthesis" can include developing new theory, tests of general hypotheses, or bringing together established or emerging areas of ecology. Confirming or extending the established literature, by for example showing results that are novel for a new taxon, or purely applied research, is given low priority.