2.5. Formatting data and statistics
Although the same reference databases were used, the taxonomic ranking
system, such as phylum and class, did not deliver comparable formats in
terms of taxonomic descriptions. Therefore, each individual identified
was assigned to its taxonomic ID lineage based on the NCBI taxonomy
database (Sayers et al., 2020) to compare the same taxonomic levels
among methods.
Similarity analyses were performed with Vegan (Oksanen et al., 2008)
using the Bray-Curtis similarity test and similarities between methods
were compared by a Mantel test. To compare relative abundance data, the
count of sequences was standardized to the total number of reads per
sample (Hellinger, decostand).