Van Gaever, S.; Vanreusel, A.; Hughes, J.; Bett, B.; Kiriakoulakis, K. (1999). The macro- and micro-scale patchiness of meiobenthos associated with the Darwin Mounds (north-east Atlantic). Journal of the Marine Biological Association of the UK. 84(3): 547-556.
Van Gaever, S.; Vanreusel, A.; Hughes, J.; Bett, B.; Kiriakoulakis, K.
The macro- and micro-scale patchiness of meiobenthos associated with the Darwin Mounds (north-east Atlantic)
Journal of the Marine Biological Association of the UK
NeMys doc_id: 18004
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Meiobenthic community structure was investigated at di¡erent spatial scales (from 100 metres to
centimetres) on and adjacent to a group of coral-topped sandy mounds in the bathyal north-east Atlantic
(Darwin Mounds, Rockall Trough) and related to the environmental conditions in the area, mainly
di¡erences in sediment organic carbon content and presence of biogenic structures. Meiobenthos
abundances were similar to those observed in other deep-sea sites, with nematodes representing at least
94% of the total community. The dominant nematode genera were Microlaimus, followed by Sabatieria,
Richtersia, Rhynchonema and Trefusia, together with typical deep-sea genera (e.g. Halalaimus and
Acantholaimus). Multivariate analysis of nematode generic relative abundances at the di¡erent stations
indicated that there was no signi¢cant in£uence on distribution resulting from large scale topographic
and biogeochemical conditions around the mounds. The same genera were associated with dead tests of
the xenophyophore Syringammina fragilissima and in the surrounding sediments. The vertical distribution of
nematodes on and adjacent to the mound showed some unusual features, as the deeper layers of the
sediments were inhabited by stilbonematids. These genera harbour ectosymbiotic, chemoautotrophic
bacteria and have not previously been recorded from the deep sea. The occurrence of stilbonematids in
notable numbers in the subsurface layers of the sediments in the vicinity of the Darwin Mounds provides
evidence for the occurrence of anoxic microenvironments.