Discussion
In the current study, regardless of sample size (10 g, 0.5 g) and
bioinformatics pipeline (ESVs, 97% OTUs, 95% OTUs) applied, we found
highly comparable diatom community patterns between metabarcoding data
and microscopic inventories from lake sediment samples. This was
especially pronounced between the metabarcoding treatments, i.e.,
amplicons from 10 g and 0.5 g of DNA extracts (HTS 10 and HTS 0.5,
respectively). Although the per-sample diatom richness was not
significantly correlated between microscopy and metabarcoding data,
community analyses indicated consistent patterns of environmental
variables shaping the diatom community structures, irrespective of
sample-size and bioinformatics pipeline used. This further demonstrates
that metabarcoding is a viable alternative to detect diatom-environment
relationships.