Publication Date:
2023-06-21
Description:
The Central Arctic Ocean is one of the most oligotrophic oceans on Earth because of its sea-
ice cover and short productive season. Nonetheless, across the peaks of extinct volcanic
seamounts of the Langseth Ridge (87°N, 61°E), we observe a surprisingly dense benthic
biomass. Bacteriosponges are the most abundant fauna within this community, with a mass
of 460 g C m−2 and an estimated carbon demand of around 110 g C m−2 yr−1, despite export
fluxes from regional primary productivity only sufficient to provide 〈1% of this required
carbon. Observed sponge distribution, bulk and compound-specific isotope data of fatty acids
suggest that the sponge microbiome taps into refractory dissolved and particulate organic
matter, including remnants of an extinct seep community. The metabolic profile of bacter-
iosponge fatty acids and expressed genes indicate that autotrophic symbionts contribute
significantly to carbon assimilation. We suggest that this hotspot ecosystem is unique to
the Central Arctic and associated with extinct seep biota, once fueled by degassing of the
volcanic mounts.
Repository Name:
EPIC Alfred Wegener Institut
Type:
Article
,
isiRev
,
info:eu-repo/semantics/article
Format:
application/pdf