Fig. 2: Ecological status of microbial communities in the surface ocean.

a Principal component analysis showing the distinct patterns of microbial communities in ocean samples belonging to different types of ecological status. The detailed pairwise comparisons for each microbial index between ecological statuses were performed by the Kruskal‒Wallis H test with Dunn’s test, which can be found in Supplementary Data 7. b Global distribution of different types of ecological status under current environmental conditions. c Different types of ecological statuses exhibited different compositions of ocean microbial communities. Compared with the other ecological status types, ES4 had the highest abundance of Cyanobacteria. d Different types of ecological status had different microbial community diversities (represented by the Shannon index). ES7 had the highest diversity, while ES4 had the lowest. ES1 showed the median level of diversity. Data are presented as box plots with minima, lower quartile, center, upper quartile, maxima, and whiskers. The outliers of boxes were not shown. The number of biologically independent samples of each type of ecological status were shown under the boxes. Different letters represented the significant difference (p < 0.05) determined by Kruskal–Wallis H test with pairwise comparisons (Dunn’s test). e The biogeochemical potential of ocean microbes varied with different types of ecological status. In total, compared with the other samples, ES4 exhibited the highest functional potential in biogeochemical cycles; however, it had a low sulfur oxidation ability. Heatmap exhibited the relative abundance (scaled as Z-Score) of each pathway in each type of ecological status. ATP adenosine triphosphate, Pta-Ack phosphate acetyltransferase-acetate kinase, 3HP/4HB 3-hydroxypropionate/4-hydroxybutyrate.