The impact of Lanice conchilega on the soft-bottom benthic ecosystem in the North Sea
Van Hoey, G.; Vincx, M.; Degraer, S. (2006). The impact of Lanice conchilega on the soft-bottom benthic ecosystem in the North Sea, in: Van Hoey, G. Spatio-temporal variability within the macrobenthic Abra alba community, with emphasis on the structuring role of Lanice conchilega = Ruimtelijke en temporele variabiliteit binnen de macrobenthische Abra alba gemeenschap met nadruk op de structurerende rol van Lanice conchilega. pp. 117-133
In: Van Hoey, G. (2006). Spatio-temporal variability within the macrobenthic Abra alba community, with emphasis on the structuring role of Lanice conchilega = Ruimtelijke en temporele variabiliteit binnen de macrobenthische Abra alba gemeenschap met nadruk op de structurerende rol van Lanice conchilega. PhD Thesis. Universiteit Gent. Faculteit Wetenschappen: Gent. 187 pp., more
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Keywords |
Sediments Species diversity Taxa > Species > Associated species Lanice conchilega (Pallas, 1766) [WoRMS] ANE, North Sea [Marine Regions] Marine/Coastal; Brackish water |
Abstract |
The tube building polychaete Lanice conchilega has a wide distribution and can form dense aggregations. Unfortunately, the effects of L. conchilega on the surrounding benthic community have received little attention, especially in subtidal areas. Therefore, the effects of the presence of L.conchilega on the abundance, species richness, diversity and species composition of the North Sea benthos in relation to sedimentology and depth were evaluated in the present paper. The results show that L. conchilega does have an effect on the benthic density and species richness in soft-bottom sediments. The density of the benthic species increased and was significantly (positively) correlated with the density of L. conchilega. Furthermore, the species richness increased with increasing density of L. conchilega. This trend was, however, not consistent: the number of species no longer increased or even decreased after reaching a certain density of L. conchilega (> 500 ind/m²). The same overall pattern was detected concerning the expected number of species. The N1 - diversity index showed similar or slightly higher values in L. conchilega patches compared to patches without L. conchilega.The effects on density and diversity were most pronounced in shallow fine sands, which are the preferred habitat of L. conchilega, and less in deep fine sands. The changes in benthic characteristics result from the alterations of the habitat by L. conchilega (hydrodynamics, sediment stability, improved oxygen) and the complex interactions between the benthic organisms and the biogenic structures consisting of L. conchilega tubes. A lot of benthic species can profit from the creation, modification and maintenance of that habitat by L. conchilega, which results in an increased density and species richness in L. conchilega patches compared to the surrounding soft-bottom sediments. Finally, the results indicated that L. conchilega has an effect on the benthos present in a particular habitat, rather than forming its own association. |
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