{"title":"Structure and vulnerability of the ichthyochory network in wetland forests of Central Amazonia","authors":"Gilvan Costa, Bianca Weiss, Maria Teresa Fernandez Piedade, Efrem Jorge Ferreira, Leonardo Maltchik","doi":"10.1111/eff.12780","DOIUrl":null,"url":null,"abstract":"<p>The interaction between fish and plants is vital for the dynamics of ecosystems since it influences plant distribution and regeneration patterns. In the floodable areas of the Amazon, these interactions are mainly structured by the flood pulse, which enables seed dispersal via water (hydrochory) and fish (ichthyochory), and which contributes to the formation of complex mutualistic networks. Our study evaluated the structure (modularity, nestedness, specialisation, and robustness) of the network of dispersal of seeds by frugivorous fish in a floodplain forest in Central Amazonia. We expect the binary network to have a nested pattern, while the weighted network is expected to have a non-nested structure; that generalist frugivorous species should constitute the core of the network, while specialist frugivorous species will be peripheral; that the size of fish and seeds is related to specialisation, and that the robustness of the network weakens as generalist frugivorous fish are removed. We found 5012 intact seeds from 49 plant species in the digestive tracts of 11 species of frugivorous fish. A nested and modular pattern was found for the binary and weighted networks, albeit with a low degree of nestedness. Our network proved relatively robust when the frugivores were removed, whereby all the fish and plant species became peripheral. No relationship was found between the size of the fish and the seeds and the degree of specialisation. Considering the anthropogenic impacts that can cause modifications in seed dispersal networks, knowing the structure of mutualistic networks is fundamental in order to be able infer the vulnerability of the interactions as a result of changes in the ecosystem.</p>","PeriodicalId":11422,"journal":{"name":"Ecology of Freshwater Fish","volume":null,"pages":null},"PeriodicalIF":1.6000,"publicationDate":"2024-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Ecology of Freshwater Fish","FirstCategoryId":"97","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1111/eff.12780","RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"FISHERIES","Score":null,"Total":0}
引用次数: 0
Abstract
The interaction between fish and plants is vital for the dynamics of ecosystems since it influences plant distribution and regeneration patterns. In the floodable areas of the Amazon, these interactions are mainly structured by the flood pulse, which enables seed dispersal via water (hydrochory) and fish (ichthyochory), and which contributes to the formation of complex mutualistic networks. Our study evaluated the structure (modularity, nestedness, specialisation, and robustness) of the network of dispersal of seeds by frugivorous fish in a floodplain forest in Central Amazonia. We expect the binary network to have a nested pattern, while the weighted network is expected to have a non-nested structure; that generalist frugivorous species should constitute the core of the network, while specialist frugivorous species will be peripheral; that the size of fish and seeds is related to specialisation, and that the robustness of the network weakens as generalist frugivorous fish are removed. We found 5012 intact seeds from 49 plant species in the digestive tracts of 11 species of frugivorous fish. A nested and modular pattern was found for the binary and weighted networks, albeit with a low degree of nestedness. Our network proved relatively robust when the frugivores were removed, whereby all the fish and plant species became peripheral. No relationship was found between the size of the fish and the seeds and the degree of specialisation. Considering the anthropogenic impacts that can cause modifications in seed dispersal networks, knowing the structure of mutualistic networks is fundamental in order to be able infer the vulnerability of the interactions as a result of changes in the ecosystem.
期刊介绍:
Ecology of Freshwater Fish publishes original contributions on all aspects of fish ecology in freshwater environments, including lakes, reservoirs, rivers, and streams. Manuscripts involving ecologically-oriented studies of behavior, conservation, development, genetics, life history, physiology, and host-parasite interactions are welcomed. Studies involving population ecology and community ecology are also of interest, as are evolutionary approaches including studies of population biology, evolutionary ecology, behavioral ecology, and historical ecology. Papers addressing the life stages of anadromous and catadromous species in estuaries and inshore coastal zones are considered if they contribute to the general understanding of freshwater fish ecology. Theoretical and modeling studies are suitable if they generate testable hypotheses, as are those with implications for fisheries. Manuscripts presenting analyses of published data are considered if they produce novel conclusions or syntheses. The journal publishes articles, fresh perspectives, and reviews and, occasionally, the proceedings of conferences and symposia.