Table 3.
Summary of key water quality parameters classified by water type
| Parameter | Blank | Fresh water pond | Rice paddies | Rain water | Shrimp ponds | Tidal channel Oct. | Tidal channel May | Tube well | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Number n | 4 | 44 | 18 | 3 | 18 | 9 | 14 | 81 | ||||||||
| Avg. | 1 σ | Avg. | 1 σ | Avg. | 1 σ | Avg. | 1 σ | Avg. | 1 σ | Avg. | 1 σ | Avg. | 1 σ | Avg. | 1 σ | |
| Eh (mV) | 273 | 126 | 276 | 77 | 173 | 68 | 325 | 162 | 246 | 78 | 279 | 141 | 69 | 97 | ||
| pH | 8.2 | 0.6 | 8.2 | 0.7 | 7.3 | 1.2 | 8.1 | 0.4 | 7.8 | 0.8 | 7.4 | 0.4 | 6.9 | 0.4 | ||
| Salinity (ppt) | 1.02 | 0.69 | 0.91 | 0.55 | 0.02 | 0.02 | 14.76 | 3.91 | 0.43 | 0.26 | 15.14 | 4.48 | 3.64 | 2.00 | ||
| Geom. mean As (μg/L) | −2.22 | −2.0 | 0.3 | −2.3 | 0.4 | −1.8 | 0.4 | −2.4 | 0.4 | −1.8 | 0.4 | −1.4 | 0.6 | |||
| Geom. mean S (mg/L) | −0.63 | 0.67 | 1.6 | 0.3 | 1.4 | 0.4 | −0.4 | 0.3 | 2.7 | 0.2 | 1.0 | 0.3 | 2.8 | 0.1 | 0.7 | 0.8 |
| Geom. mean DOC (mg/L) | 0.59 | 0.18 | 1.0 | 0.2 | 0.8 | 0.1 | 0.2 | 0.1 | 1.2 | 0.3 | 0.8 | 0.2 | 0.8 | 0.2 | 1.4 | 0.2 |
| >10 μg/L As | 41% | 22% | 0% | 78% | 11% | 71% | 83% | |||||||||
| >50 μg/L As | 2% | 0% | 0% | 11% | 0% | 7% | 47% | |||||||||
| >2 mS/cm | 36% | 28% | 0% | 100% | 11% | 100% | 100% | |||||||||