Publication Date:
2017-02-01
Description:
The metazoan meiofauna has been studied in multiple corer samples collected in the
Porcupine Seabight and on the Porcupine Abyssal Plain (NE Atlantic, 49.3°-52.3°N).
Cores were taken at 500 rn intervals between depths of 500 rn and 4 850 m. With
increasing depth the total meiofaunal abundance declined from 2 604 to 315 individuals
per 10 cm-2 and the biomass from 1.16 to 0.35 mg per 10 cm- 2 (ash-free dry weight).
This depth-related decrease in standing stock was significantly correlated with the
amounts of sediment-bound chloroplastic pigments (chlorophyll a, pheopigments) in
a parallel set of samples. These pigments provide a measure to estimate the flux of
primary organic matter to the seafloor. The depth transect in the Porcupine Seabight
is compared with similar transects off Portugal and north Morocco. AU three transects
revealed major decreases in meiofaunal density and biomass between 500 rn and
1 500 rn, roughly equivalent to the archibenthic zone, and also between the continental
rise and the abyssal plain. Between 2 000 rn and 4 000 rn, however, the standing stock
decreased only slightly. The metazoan meiofauna in the Porcupine Seabight samples
consisted mainly of nematodes (80.0-91.5%) with harpacticoids and nauplii generally
second in abundance (3.3-6.8%). Between 500 rn and 2 000 rn, polychaetes and bivalves
contributed substantially to the meiofauna.
Type:
Article
,
PeerReviewed
Format:
text
Permalink
