Soft-sediment macrobenthic species distributions in estuaries: from pattern to prediction
Ysebaert, T.J.; Herman, P.M.J. (2002). Soft-sediment macrobenthic species distributions in estuaries: from pattern to prediction, in: ECSA Local Meeting: ecological structures and functions in the Scheldt Estuary: from past to future, Antwerp, Belgium October 7-10, 2002: abstract book. pp. 39
In: (2002). ECSA Local Meeting: Ecological structures and functions in the Scheldt Estuary: from past to future, Antwerp, Belgium October 7-10, 2002: abstract book. University of Antwerp: Antwerp. 73 + 1 cd-rom pp., more
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Available in | Authors |
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Document type: Conference paper
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Keywords |
Abundance Aquatic communities > Benthos Aquatic communities > Benthos > Zoobenthos Composition > Sediment composition Environmental conditions Physics > Mechanics > Dynamics Population characteristics > Biomass Properties > Chemical properties > Salinity Spatial variations Taxa > Species > Indicator species Temporal variations Water bodies > Coastal waters > Coastal landforms > Coastal inlets > Estuaries ANE, Europe, Northwest [Marine Regions]; Belgium, Schelde R. [Marine Regions]
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Abstract |
There is growing awareness of the need to address the issue of scale more explicitly in (benthic) ecology. If spatial heterogeneity is important for the functioning of ecosystems, ecosystem models should include the spatial organization of populations, species assemblages and their environment. Macrobenthos plays an important role in the system dynamics of estuaries and is a good bioindicator. However, few attempts have been made to model and predict responses of macrobenthic species to environmental variables at different spatial scales. For the Scheldt estuary (NW-Europe) a large macrobenthic database is available, covering different spatial (from a single tidal flat to the complete estuary) and temporal (from month to decade) scales. Apart from the biotic information, this database contains several environmental variables such as salinity, current velocities and sediment characteristics. Besides more classical approaches such as classification and ordination (e.g. direct gradient analysis), we applied geostatistics and regression models (e.g. generalized linear models such as logistic regression) to the data in order to elucidate the role of environmental conditions in explaining the occurrence (presence/absence, abundance, biomass) of the benthic macrofauna at different spatial and/or temporal scales. Our results showed that at meso-scales (>100m-10 km) a considerable fraction of the variation in occurrence, density and biomass of macrobenthic species correlated very well with physical factors (depth, tidal current velocity, sediment composition). At larger scales within the estuary salinity changed these relations significantly. However, a large and statistically significant amount of unexplained variation still occurred at the smaller scales (< 100 m). Possible mechanisms evoking these small-scale patterns are discussed. |
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