Table 2. Top 20 OTUs and their relative proportions in bacterial communities’ sampled from HXH and DC, respectively.

No.	HXH			DC (Except DC7)
		%	Taxonomy	No.	%	Taxonomy
1	OTU004	11.59	Flavobacterium, gelidilacus	OTU001	5.63	Synechococcaceae, Synechococcus
2	OTU002	6.82	Actinomycetales, ACK-M1	OTU007	3.06	Pirellulales, Pirellulaceae
3	OTU005	5.62	Actinomycetales, ACK-M1	OTU010	2.67	Pirellulales, Pirellulaceae
4	OTU008	5.39	Rickettsiales, Pelagibacteraceae	OTU009	2.45	Chitinophagaceae, Sediminibacterium
5	OTU006	4.77	Streptococcaceae, Lactococcus	OTU002	2.19	Actinomycetales, ACK-M1
6	OTU018	3.61	Acidibacteriales, C111	OTU011	1.92	Acinetobacter, guillouiae
7	OTU012	3.31	Burkholderiales, Comamonadaceae	OTU013	1.80	Alphaproteobacteria, Rhizobiales
8	OTU024	2.01	Pedosphaerales, R4-41B	OTU006	1.79	Streptococcaceae, Lactococcus
9	OTU011	1.91	Acinetobacter, guillouiae	OTU017	1.58	Acidibacteriales, C111
10	OTU019	1.77	Pseudomonas, fragi	OTU005	1.46	Actinomycetales, ACK-M1
11	OTU049	1.65	Moraxellaceae, Perlucidibaca	OTU016	1.32	Acetobacteraceae, Roseomonas
12	OTU051	1.43	Moraxellaceae, Acinetobacter	OTU023	1.29	Chlorobi, OPB56
13	OTU079	1.20	Gemmatales, Gemmataceae	OTU015	1.26	Alphaproteobacteria, Rhizobiales
14	OTU064	1.12	Comamonadaceae, Limnobacter	OTU021	1.23	Actinobacteria, Actinomycetales
15	OTU015	1.08	Alphaproteobacteria, Rhizobiales	OTU014	1.04	Chthoniobacteraceae, Candidatus_Xiphinematobacter
16	OTU036	1.07	Streptococcaceae, Lactococcus	OTU008	0.98	Rickettsiales, Pelagibacteraceae
17	OTU081	1.06	Caldilineaceae, Caldilinea	OTU028	0.96	Chlorobi, OPB56
18	OTU026	1.00	Mycobacteriaceae, Mycobacterium	OTU030	0.95	Pirellulales, Pirellulaceae
19	OTU014	0.99	Chthoniobacteraceae, Candidatus_Xiphinematobacter	OTU029	0.82	Pirellulales, Pirellulaceae
20	OTU101	0.82	Bacteria, Bacteroidetes	OTU032	0.82	Saprospirales, Chitinophagaceae