Post-extraction evolution of a macrobenthic community on the intensively extracted Kwintebank site in the Belgian part of the North Sea
Moulaert, I.; Hostens, K. (2007). Post-extraction evolution of a macrobenthic community on the intensively extracted Kwintebank site in the Belgian part of the North Sea. CM Documents - ICES, CM 2007(A:12). ICES: Copenhagen. 13 pp. Part of: ICES CM Documents - ICES. ICES: Copenhagen. ISSN 1015-4744, more |
Available in | Authors | | Document type: Conference paper
|
Keywords | Dredging (excavation) Macrobenthos Recovery Sedimentary structures > Bed forms > Banks (topography) > Sand banks ANE, Belgium, Belgian Continental Shelf (BCS) [Marine Regions]; ANE, Belgium, Flemish Banks, Kwinte Bank [Marine Regions] Marine/Coastal |
Abstract | The Kwintebank, a highly dynamic sandbank in the western Belgian part of the North Sea, is highly extracted, mainly due to the short distance to the coast and the suitability of the sand for construction purposes. After 30 years of exploitation, a depression was formed in the central part of the Kwintebank. To allow the geomorphologic rehabilitation of the area, it was decided to cease extraction in this part of the exploitation zone in 2003. The recovery of the macrobenthos in this depression was monitored for several years through the analysis of Van Veen grab samples taken twice a year at six locations in the depression and at several locations spread over the Kwintebank. The poor macrobenthic community that was found in the central depression directly after the cessation of the extraction activities, clearly evolved to a community with higher densities, species richness and diversity within three years after the sand extraction activities had stopped. The species with the highest increase were the interstitial polychaetes Hesionura elongata and Polygordius appendiculatus, juvenile and adult Nephtys cirrosa and the amphipod Urothoe brevicornis. These are characteristic species also for the other highly dynamic sandbanks of the Belgian continental shelf. As the 'central' Kwintebank site will remain closed for another 3 years, there is an opportunity to further investigate the recolonisation/recovery of the macrobenthic community. |
|