Pelage L., Ferreira V., Lucena-Frédou F., Ferreira G. V. B., Gonzalez J. G., Viana A. P., Lira A. S., Munaron Jean-Marie, Frédou T., Ménard Frédéric, Le Loc'h François. (2022). Estuarine food web structure and relative importance of organic matter sources for fish in a highly connected Northeastern Brazil ecotone. Estuarine Coastal and Shelf Science, 275, p. 107972 [11 p.]. ISSN 0272-7714.
Titre du document
Estuarine food web structure and relative importance of organic matter sources for fish in a highly connected Northeastern Brazil ecotone
Année de publication
2022
Auteurs
Pelage L., Ferreira V., Lucena-Frédou F., Ferreira G. V. B., Gonzalez J. G., Viana A. P., Lira A. S., Munaron Jean-Marie, Frédou T., Ménard Frédéric, Le Loc'h François
Source
Estuarine Coastal and Shelf Science, 2022,
275, p. 107972 [11 p.] ISSN 0272-7714
The lack of knowledge about highly anthropised tropical ecosystems poses a problem for their conservation. Using carbon and nitrogen stable isotopes, we studied the food web structure of the estuarine ecotone of the Santa Cruz Channel (SCC), which constitutes a critical habitat for many socio-economically important species in northeast Brazil. Therefore, we assessed the spatial (estuary/coast) and seasonal (dry/rainy) isotopic variation of basal food sources, invertebrates and fishes. We also used Bayesian mixing models to trace the origin (estuary vs coast) of the organic matter sources supporting SCC fishes food webs according to their feeding habits. We found a wide range of delta C-13 and delta N-15 values for basal sources, invertebrates, and fish in coastal and estuarine envi-ronments, but isotopic compositions showed greater variability in the estuary. This illustrated the heterogeneity of primary producers and sources in estuaries, intensified by SCC morphology, as both accesses to the sea provide strong mixing between riverine and marine inputs. Additionally, we found differences between fish isotope compositions according to their guilds. Coastal basal sources significantly support zoobenthivorous, piscivorous and zooplanktivorous fish estuarine food webs. Conversely, detritivores are supported by enriched sources of organic matter, especially during the dry season, which may be derived from terrestrial inputs. As contaminated land-based inputs can affect food webs and coastal fisheries, developing a management plan that includes all interconnected habitats is necessary.
Plan de classement
Sciences fondamentales / Techniques d'analyse et de recherche [020]
;
Ecologie, systèmes aquatiques [036]
Description Géographique
BRESIL ; ATLANTIQUE ; ZONE TROPICALE ; PERNAMBUCO ; SANTA CRUZ CANAL
Localisation
Fonds IRD [F B010085938]
Identifiant IRD
fdi:010085938
