Figure 4. Alpha diversity metrics boxplot of sites by sources.
Overall, differences in microbial community structure were observed between seawater, sediment, skin, and midgut samples collected from different sites. Microbial communities from different sources were all distinct from one another (Table 2), although skin and midgut samples clustered closer together (Figure 5A). However, these similarities between skin and midgut microbiota composition varied across sites (Table 3). A deviation of seawater microbiota in Starfish Bay could be observed along PC2, away from the two other sites (Figure 5A). Community structure showed a high influence on the interaction between source and site factors as can be seen in the clustering tendency of the samples (Figure 5A). A general higher to lower dispersion trend in beta diversity from highly polluted to low polluted sites was observed in seawater and sediment samples. On the other hand, dispersion patterns in hosts across the three sites did not align with that of the environmental sources. In midgut samples, a general trend of higher beta diversity dispersion in the least polluted site was observed (Figure 5B, Table 3).