Spatial variation of the macrobenthos species and communities of the Belgian Continental Shelf and the relation to environmental variation
Moulaert, I.; Hostens, K.; Hillewaert, H.; Wittoeck, J. (2007). Spatial variation of the macrobenthos species and communities of the Belgian Continental Shelf and the relation to environmental variation. CM Documents - ICES, CM 2007(A:09). ICES: Copenhagen. 13 pp.
Part of: ICES CM Documents - ICES. ICES: Copenhagen. ISSN 1015-4744, more
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| Keywords |
Macrobenthos
Spatial variations
ANE, Belgium, Belgian Continental Shelf (BCS) [Marine Regions]
Marine/Coastal |
| Abstract |
Macrobenthos data for the Belgian Continental Shelf were used (1) to give an overview of the spatial pattern of the different macrobenthic species and communities of the Belgian Continental Shelf and (2) to examine the influence of different environmental variables on the spatial distribution of the macrobenthos species and communities on different spatial scales. The Belgian part of the North Sea is a highly dynamic area with a continuous succession of gullies and sandbanks. A variety of human activities like sand extraction, dredge dumping and fishing also affect the ecosystem. Samples were collected in the framework of different monitoring programs during 2004 and 2005 using the same sampling techniques. Total abundance, number of species and diversity indices were calculated and used for spatial comparison. The differences in community structure were investigated through multivariate analyses. Several a-biotic variables were measured and used in statistical tests to investigate the relation with the macrobenthos on different spatial scales. Multivariate analysis distinguished five major community groups, with a clear separation between the coastal and the offshore samples. The groups were characterised by the presence and/or absence of certain species and the relative abundance of the different taxonomic and feeding type groups. The average density, species richness and diversity were highly variable within each group. The distribution patterns of certain species were clearly related to the environmental variability. Univariate measures correlated best with depth and salinity, whereas multivariate analysis identified median grain size, mud content and salinity as the major environmental variables influencing the faunal patterns. |
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