Additional file 9 of Metagenomic insights into the microbial communities of inert and oligotrophic outdoor pier surfaces of a coastal city

Additional file 9: Figure S6. Relative abundance and composition of iron-related functions in the pier surface microbiomes. (a) Relative abundance of four categories of iron-related genes delineated by surface type and material. Statistics cannot be determined for genes associated with iron oxidation owing to insufficient samples for the two surface materials. (b) Principal coordinate analysis of the Bray–Curtis dissimilarity based on the abundance and membership of iron-related proteins in the surface microbiomes.