Movement of carbon among estuarine habitats and its assimilation by invertebrates

dc.contributor.authorConnolly, R. M.en
dc.contributor.authorGorman, Danielen
dc.contributor.authorGuest, Michaela A.en
dc.contributor.schoolSchool of Earth and Environmental Sciencesen
dc.date.issued2005en
dc.description.abstractWe measured the extent of movement of carbon and its assimilation by invertebrates among estuarine habitats by analysing carbon stable isotopes of invertebrates collected along transects crossing the boundary of two habitats. The habitats were dominated by autotrophs with distinct isotope values: (1) mudflats containing benthic microalgae (mean −22.6, SE 0.6‰) and (2) seagrass and its associated epiphytic algae (similar values, pooled mean −9.8, 0.5‰). Three species of invertebrates were analysed: a palaemonid shrimp, Macrobrachium intermedium, and two polychaete worms, Nephtys australiensis and Australonereis ehlersi. All species had a similar narrow range of isotope values (−9 to −14‰), and showed no statistically significant relationship between position along transect and isotope values. Animals were relying on carbon from seagrass meadows whether they were in seagrass or on mudflats hundreds of metres away. Particulate organic matter collected from superficial sediments along the transects had similar values to animals (mean −11.1, SE 1.3‰) and also showed no significant relationship with position. The isotope values of these relatively immobile invertebrates and the particulate detritus suggest that carbon moves from subtidal seagrass meadows to mudflats as particulate matter and is assimilated by invertebrates. This assimilation might be direct in the case of the detritivorous worm, A. ehlersi, but must be via invertebrate prey in the case of the carnivorous worm, N. australiensis and the scavenging shrimp, M. intermedium. The extent of movement of carbon among habitats, especially towards shallower habitats, is surprising since in theory, carbon is more likely to move offshore in situations such as the current study where habitats are in relatively open, unprotected waters.en
dc.description.statementofresponsibilityRod M. Connolly, Daniel Gorman and Michaela A. Guesten
dc.identifier.citationOecologia, 2005; 144(4):684-691en
dc.identifier.doi10.1007/s00442-005-0167-4en
dc.identifier.issn0029-8549en
dc.identifier.urihttp://hdl.handle.net/2440/55634
dc.language.isoenen
dc.publisherSpringeren
dc.subjectCrustacea; Estuary; Polychaeta; Stable isotopes; Trophic subsidyen
dc.titleMovement of carbon among estuarine habitats and its assimilation by invertebratesen
dc.typeJournal articleen

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