Data from: Spatio-temporal monitoring of deep-sea communities using metabarcoding of sediment DNA and RNA

We assessed spatio-temporal patterns of diversity in deep-sea sediment
communities using metabarcoding. We chose a recently developed eukaryotic
marker based on the v7 region of the 18S rRNA gene. Our study was
performed in a submarine canyon and its adjacent slope in the Northwestern
Mediterranean Sea, sampled along a depth gradient at two different
seasons. We found a total of 5,569 molecular operational taxonomic units
(MOTUs), dominated by Metazoa, Alveolata and Rhizaria. Among metazoans,
Nematoda, Arthropoda and Annelida were the most diverse. We found a marked
heterogeneity at all scales, with important differences between layers of
sediment and significant changes in community composition with zone
(canyon vs slope), depth, and season. We compared the information obtained
from metabarcoding DNA and RNA and found more total MOTUs and more MOTUs
per sample with DNA (ca. 20% and 40% increase, respectively). Both
datasets showed overall similar spatial trends, but most groups had higher
MOTU richness with the DNA template, while others, such as nematodes, were
more diverse in the RNA dataset. We provide metabarcoding protocols and
guidelines for biomonitoring of these key communities in order to generate
information applicable to management efforts.