Macrobenthic recovery from hypoxia in an estuarine tidal mudflat
Van Colen, C.; Montserrat, F.; Vincx, M.; Herman, P.M.J.; Ysebaert, T.J.; Degraer, S. (2009). Macrobenthic recovery from hypoxia in an estuarine tidal mudflat, in: Van Colen, C. Tidal flat macrobenthos ecology, recolonisation and succession = Ecologie, herkolonisatie en successie van het macrobenthos in slikken. pp. 35-57 In: Van Colen, C. (2009). Tidal flat macrobenthos ecology, recolonisation and succession = Ecologie, herkolonisatie en successie van het macrobenthos in slikken. PhD Thesis. Universiteit Gent; Faculteit Wetenschappen; Afdeling Mariene Biologie: Gent. ISBN 978-90-902416-6-1. 300 pp., more Related to:Van Colen, C.; Montserrat, F.; Vincx, M.; Herman, P.M.J.; Ysebaert, T.J.; Degraer, S. (2008). Macrobenthic recovery from hypoxia in an estuarine tidal mudflat. Mar. Ecol. Prog. Ser. 372: 31-42. https://dx.doi.org/10.3354/meps07640, more | |
Keywords | Colonisation Interactions Macrobenthos Sedimentary structures > Mud flats Succession (ecological) Topographic features > Landforms > Coastal landforms > Tidal flats ANE, Netherlands, Westerschelde [Marine Regions] Marine/Coastal; Brackish water | Author keywords | Macrobenthos (re)colonisation; Succession; Physical-biological interactions; Exploitation competition for food; Tidal mudflat; Westerschelde estuary |
Abstract | Macrobenthic recolonisation patterns after complete defaunation resulting from experimentally induced hypoxia were investigated in a polyhaline, estuarine mudflat. Based on simultaneous sampling of biotic and environmental variables in replicated 16 m2 control and defaunated plots, with a high resolution in time during 6 mo, the ecological interactions related to the macrobenthos reassembly were elucidated. Colonisation was predominantly determined by juvenile recruitment, and 3 successional stages were identified, each characterised by different species assemblages and environmental characteristics. During recovery, a shift in functional group dominance from mobile surface deposit feeders to tube-dwelling surface deposit feeders to biodestabilising taxa occurred, while their proportional dominance remained quite stable in the control plots throughout the experiment. Species colonisation patterns of later colonists revealed positive interactions with early colonizing opportunistic tube-building polychaetes Pygospio elegans, while later successional species (Heteromastus filiformis, Macoma balthica) adversely affected the stable, favourable conditions created by the tube-building infauna. Transitions between different successional stages were related to recruitment of species, changes in environmental characteristics (oxygenation state of the sediment), direct and indirect ecological interactions (bio[de]stabilisation, exploitation competition for food). In general, our study suggests that macrobenthic reassembly after hypoxia is related to different types of interactions, all acting in a unique manner. Hence, macrobenthic successional dynamics in a tidal mudflat habitat should be considered as a dynamic process, related to resource availability, natural temporal variation, life history traits (e.g. opportunistic behaviour) and bio-engineering capacities of the colonising species. |
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