Table 2.

Three types of abundance underestimation based on comparisons among datasets across the four-depth sediments in location S2 for bacterial taxa with higher abundances in MT-16S than 16S rDNA amplicons.

	cDNA (%)a	rDNA (%)b	MT-16S (%)c
	mean ± SD	mean ± SD	mean ± SD
Type I
Phylum
Acidobacteria	5.36 ± 0.78AB	1.61 ± 1.06C	4.45 ± 0.56A
Order
Desulfobacterales	7.54 ± 1.53AB	3.24 ± 1.95C	9.33 ± 0.81A
Myxococcales	1.07 ± 0.10AB	0.28 ± 0.14C	1.17 ± 0.12A
Type II
Phylum
Elusimicrobia	0.00 ± 0.00B	0.00 ± 0.00BC	1.28 ± 0.67A
Lentisphaerae	0.00 ± 0.00B	0.00 ± 0.00BC	0.30 ± 0.08A
Planctomycetes	0.00 ± 0.00B	0.00 ± 0.00BC	3.37 ± 0.59A
Verrucomicrobia	0.02 ± 0.02B	0.01 ± 0.00BC	3.15 ± 0.18A
Type III
Phylum
Chloroflexi	11.77 ± 7.29B	5.33 ± 4.62C	20.94 ± 5.89A
Class
Subgroup 22 (Acidobacteria)	0.82 ± 0.14B	0.21 ± 0.09C	1.63 ± 0.33A
Family
Anaerolineaceae	7.95 ± 5.93B	1.78 ± 1.25C	13.87 ± 4.57A
Bacteriovoracaceae	0.15 ± 0.03B	0.03 ± 0.02C	0.39 ± 0.11A

Different letters (A, B, C) following the abundances indicate a significant difference (P < 0.05) based on Wilcoxon signed rank test. ^aAverage proportions in 16S cDNA amplicon datasets for the four-depth sediment samples. ^bAverage proportions in 16S rDNA amplicon datasets for the four-depth sediment samples. ^cAverage proportions in MT-16S datasets for the four-depth sediment samples. Supplementary Table S3 provides further details.