Table 2.
Bacterial community richness and diversity indices at each treatment step and the four sampling times.
| Sample by type and date | OTUs | Coverage | ACE | Chao1 | Shannon | Simpson | |
|---|---|---|---|---|---|---|---|
| RW | Nov. | 1486 | 0.944 | 5800 | 3451 | 4.90 | 0.032 |
| Jan. | 834 | 0.976 | 2517 | 1659 | 4.58 | 0.024 | |
| May | 1480 | 0.963 | 3292 | 2502 | 5.04 | 0.027 | |
| Jul. | 1147 | 0.971 | 2830 | 2078 | 4.53 | 0.042 | |
| PROE | Nov. | 1508 | 0.952 | 4697 | 3208 | 4.49 | 0.044 |
| Jan. | 840 | 0.976 | 2347 | 1674 | 4.55 | 0.026 | |
| May | 1448 | 0.961 | 3594 | 2652 | 5.05 | 0.024 | |
| Jul. | 1522 | 0.959 | 3802 | 2836 | 4.94 | 0.030 | |
| SE | Nov. | 2459 | 0.926 | 6093 | 4289 | 5.28 | 0.031 |
| Jan. | 586 | 0.983 | 1796 | 1264 | 3.98 | 0.041 | |
| May | 608 | 0.983 | 1717 | 1285 | 3.62 | 0.074 | |
| Jul. | 957 | 0.973 | 2950 | 1973 | 3.23 | 0.193 | |
| SFE | Nov. | 1643 | 0.951 | 4730 | 3133 | 4.59 | 0.038 |
| Jan. | 649 | 0.983 | 1782 | 1335 | 4.20 | 0.034 | |
| May | 856 | 0.978 | 2134 | 1590 | 3.74 | 0.074 | |
| Jul. | 1477 | 0.961 | 3732 | 2662 | 3.78 | 0.168 | |
| PSOE | Nov. | 2878 | 0.925 | 4738 | 4258 | 6.37 | 0.008 |
| Jan. | 766 | 0.981 | 1760 | 1428 | 4.58 | 0.030 | |
| May | 1277 | 0.970 | 2558 | 2093 | 4.54 | 0.049 | |
| Jul. | 2630 | 0.940 | 4146 | 3884 | 5.89 | 0.021 | |
| BACE | Nov. | 3402 | 0.910 | 6807 | 5231 | 6.91 | 0.003 |
| Jan. | 1527 | 0.964 | 3184 | 2469 | 5.62 | 0.010 | |
| May | 1883 | 0.959 | 3677 | 2944 | 5.86 | 0.012 | |
| Jul. | 2181 | 0.953 | 4088 | 3326 | 6.15 | 0.010 | |
| DW | Nov. | 3011 | 0.917 | 4733 | 4237 | 6.13 | 0.019 |
| Jan. | 964 | 0.979 | 1425 | 1300 | 4.15 | 0.053 | |
| May | 1609 | 0.963 | 2558 | 2297 | 4.77 | 0.036 | |
| Jul. | 2612 | 0.946 | 3751 | 3444 | 5.78 | 0.036 | |
| USB | Nov. | 1185 | 0.967 | 3406 | 2245 | 4.46 | 0.038 |
| Jan. | 939 | 0.976 | 2349 | 1741 | 4.49 | 0.035 | |
| May | 655 | 0.986 | 1413 | 1047 | 4.10 | 0.045 | |
| Jul. | 1065 | 0.977 | 2256 | 1804 | 5.01 | 0.023 | |
| MSB | Nov. | 990 | 0.974 | 2644 | 1914 | 4.36 | 0.048 |
| Jan. | 806 | 0.981 | 1826 | 1437 | 4.45 | 0.034 | |
| May | 641 | 0.985 | 1574 | 1057 | 4.09 | 0.041 | |
| Jul. | 954 | 0.978 | 2357 | 1787 | 4.76 | 0.032 | |
| UBACB | Nov. | 2167 | 0.946 | 4675 | 3375 | 6.04 | 0.011 |
| Jan. | 1033 | 0.978 | 1982 | 1724 | 4.59 | 0.065 | |
| May | 974 | 0.981 | 1706 | 1427 | 4.82 | 0.037 | |
| Jul. | 1144 | 0.975 | 2321 | 1837 | 4.88 | 0.025 | |
| MBACB | Nov. | 1793 | 0.956 | 4127 | 3011 | 5.75 | 0.014 |
| Jan. | 1198 | 0.977 | 2075 | 1693 | 5.00 | 0.049 | |
| May | 914 | 0.981 | 1697 | 1520 | 4.44 | 0.064 | |
| Jul. | 1443 | 0.970 | 2779 | 2233 | 5.57 | 0.013 | |
RW, raw water; PROE, preozonation effluent; SE, sedimentation effluent; SFE, sand filtration effluent; PSOE, post-ozonation effluent; BACE, biological activated carbon effluent; DW, disinfected water; USB, upper sand biofilm; MSB, middle sand biofilm; UBACB, upper biological activated carbon biofilm; MBACB, middle biological activated carbon biofilm.