Macrobenthos of the Nansen and Amundsen Basins from the Nansen Legacy joint cruise JC2-2 in Aug/Sept 2021

Study Extent

Nansen Basin, Amundsen Basin

Sampling

Sediment samples for analysis of macrofaunal diversity, abundance and biomass were taken from multiple 11.7 cm diameter cores inserted in 50x50 cm box cores. These cores were first used for sediment community oxygen respiration and then gently sieved completely through 250 µm for macrofaunal community estimates with cold seawater. The remaining biota was then preserved in a 4% buffered formaldehyde-seawater solution that was rose Bengal-stained. This work is part of RF3 of the Nansen Legacy project, cruise JC2-2, August/September 2021. Protocol version 9 was used (10.3.9, but smaller sieve size and different contact person).

Method steps

1. In the home lab, samples were sorted to major taxa first under a stereomicroscope (partly at UiT, partly at IOPAN). Subsequently macrofauna taxa were identified to the lowest possible taxonomic level, enumerated and the weight taken. Meiofauna in the samples was identified to phylum level only. Fragments were not enumerated but weighed. Taxonomic identification my be improved for some individuals in the future.

N/A

1. Terebellida
   rank: order
2. Arthropoda
   rank: phylum
3. Cirratulidae
   rank: family
4. Tanaidacea
   rank: order
5. Annelida
   rank: phylum
6. Ostracoda
   rank: class
7. Polychaeta
   rank: class
8. Trombidiformes
   rank: order
9. Akanthophoreidae
   rank: family
10. Copepoda
    rank: class
11. Malacostraca
    rank: class
12. Spionida
    rank: order
13. Halacaridae
    rank: family
14. Nematoda
    rank: phylum
15. Nephtyidae
    rank: family
16. Animalia
    rank: kingdom
17. Spionidae
    rank: family
18. Ampharetidae
    rank: family
19. Phyllodocida
    rank: order
20. Arachnida
    rank: class

The data sets contains information on occurrence, counts and weights (per 11.7 diameter core) of benthic macrofauna at one locations (P8) in the Nansen Basin, one location on the Gakkel Ridge (P9) and two locations (P10, P11) in the Amundsen Basin, sampled in Aug/Sept 2021.