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).