Table 1.
Detection and abundance of 16S rRNA genes of anammox bacteria and total bacteria in groundwater samples from shallow dug wells
| Season | Sample type | Samples with the gene relative to all samples (detection %) | Anammox bacterial 16S rRNA gene abundance (copies L–1) | Total bacterial 16S rRNA gene abundance (copies L–1) | |||||
|---|---|---|---|---|---|---|---|---|---|
| Min | Max | Avea | Min | Max | Avea | ||||
| Dry season | Gravel subsurface | 14/24 (58%) | 1.7×105 | 7.6×106 | 1.4×106±1.9×106 | 6.3×106 | 1.7×1010 | 1.9×109±3.9×1010 | |
| Clay subsurface | 23/44 (52%) | 1.6×105 | 8.8×106 | 1.5×106±1.8×106 | 1.2×107 | 7.3×1010 | 3.3×109±1.1×1010 | ||
| Wet season | Gravel subsurface | 20/29 (69%) | 1.2×105 | 1.2×107 | 9.4×105±2.5×106 | 3.6×106 | 1.0×1011 | 5.0×109±1.9×1010 | |
| Clay subsurface | 30/55 (55%) | 4.3×104 | 3.1×106 | 5.3×105±7.3×105 | 3.3×106 | 3.0×1010 | 3.6×109±4.9×109 b | ||
| Total | 87/152 (57%) | 4.3×104 | 1.2×107 | 3.3×106 | 1.0×1011 | ||||
a Values are means±SD.
b Significantly higher (Student’s t-test, P<0.05) than total bacterial 16S rRNA gene abundance in dry season (gravel subsurface and clay subsurface) samples and wet season (gravel subsurface) samples.