Table 4. Detection and distribution of bacterial phyla (or subdivisions of Proteobacteria).
| Phylum | Total | HBM | LBM | |
|---|---|---|---|---|
| % (# OTUs) | % (# OTUs) | % (# OTUs) | ||
| Acidobacteria | 3.63 (90) | 3.59 (45) | 4.10 (78) | |
| Actinobacteria | 4.67 (116) | 6.06 (76)* | 4.73 (90)* | |
| Armatimonadetes | 0.04 (1) | 0 (0) | 0.05 (1) | |
| Bacteroidetes | 9.31 (231) | 8.45 (106)* | 9.21 (175)* | |
| Chlamydiae | 0.16 (4) | 0.16 (2) | 0.16 (3) | |
| Chlorobi | 0.08 (2) | 0 (0) | 0.11 (2) | |
| Chloroflexi | 1.69 (42) | 1.83 (23) | 1.68 (32) | |
| Cyanobacteria | 0.73 (18) | 0.80 (10) | 0.58 (11) | |
| Deinococcus-Thermus | 0.04 (1) | 0.08 (1) | 0 (0) | |
| Firmicutes | 2.98 (74) | 3.19 (40) | 2.74 (52) | |
| Fusobacteria | 0.08 (2) | 0.08 (1) | 0.11 (2) | |
| OD1 | 1.49 (37) | 1.91 (24) | 1.10 (21) | |
| OP11 | 0.32 (8) | 0.32 (4) | 0.26 (5) | |
| Planctomycetes | 6.21 (154) | 4.06 (51) | 7.21 (137) | |
| Proteobacteria | Alphaproteobacteria | 5.04 (125) | 5.82 (73)* | 4.94 (94)* |
| Betaproteobacteria | 1.09 (27) | 1.59 (20) | 0.95 (18) | |
| Gammaproteobacteria | 14.67 (364) | 15.62 (196)* | 14.52 (276)* | |
| Deltaproteobacteria | 6.93 (172) | 6.69 (84)* | 7.63 (145)* | |
| Zetaproteobacteria | 0.04 (1) | 0.08 (1) | 0 (0) | |
| Epsilonproteobacteria | 0.08 (2) | 0.08 (1) | 0.11 (2) | |
| Unclassified | 2.54 (63) | 2.23 (28)* | 2.47 (47)* | |
| Spirochaetes | 0.20 (5) | 0 (0)* | 0.26 (5)* | |
| SR1 | 0.16 (4) | 0.08 (1) | 0.16 (3) | |
| Synergistetes | 0.12 (3) | 0.16 (2) | 0.05 (1) | |
| Tenericutes | 0.04 (1) | 0 (0) | 0.05 (1) | |
| TM7 | 1.09 (27) | 1.59 (20) | 1.00 (19) | |
| Verrucomicrobia | 5.48 (136) | 6.14 (77)* | 5.89 (112)* | |
| WS3 | 0.52 (13) | 0.64 (8) | 0.53 (10) | |
| Unclassified | 30.58 (759) | 28.76 (361)* | 29.41 (559)* |
Percentages OTU per phylum are given for both sediment types (Total) and for each sediment type separately (HBM and LBM), exact numbers are given between brackets. Phyla containing previously described diatom-associated bacteria are underlined. Significant differences (*) in the number of OTUs between HBM and LBM samples were detected using a t-test (p ≤ 0.05). Reliability of significance testing was checked using the Levene’s p-value (>0.05).