Publication Date:
2018-06-25
Description:
The study presents results on the composition and vertical distribution of the near-bottom plankton community at an abyssal
site in the NE Atlantic. Plankton samples were collected at 1, 15, 50 and 100 m above bottom (mab). Whereas the
composition within the upper three layers was very similar, a major shift occurred in the immediate vicinity of the seafloor.
Between 100 and 15 mab, the plankton was dominated by Copepoda, making up more than 75% of the total abundance and
biomass (without gelatinous organisms). At 1 mab, Copepoda were still abundant, but their share decreased to ca. 50%, while
Polychaeta, Malacostraca and Chaetognatha became important groups. Within the Copepoda, the predominance of the
genus Metridia (Calanoida) in the upper layers was replaced by the genus Benthomisophria (Misophrioida) at 1 mab. Despite
enrichment in organic particles towards the bottom, the total abundance and biomass of plankton did not show marked
differences between the four layers investigated. Several hypotheses are discussed which may explain why the presumably
higher food concentrations near the deep-sea floor do not lead to increased standing stocks of the plankton community.
Type:
Article
,
PeerReviewed
Format:
text
DOI:
10.1080/17451000903150363
