Table 3.
Pearson product-moment correlation coefficients between OP concentrations and total chlorine residual concentration for each CDWDS
| OP | SW1 | SW2 | SW3 | GW |
|---|---|---|---|---|
| Legionella |
ρ −0.685; p-value 0.003* |
ρ −0.490; p-value 0.054 |
ρ −0.665; p-value 0.005* |
ρ −0.677; p-value 0.004* |
| Mycobacterium |
ρ 0.009; p-value 0.975 |
ρ −0.561; p-value 0.024* |
ρ −0.768; p-value 0.001* |
ρ −0.541; p-value 0.031* |
| Pseudomonas |
ρ −0.177; p-value 0.513 |
ρ −0.268; p-value 0.316 |
ρ −0.372; p-value 0.156 |
ρ −0.809; p-value < 0.001* |
| V. vermiformis |
ρ −0.169; p-value 0.532 |
ρ −0.224; p-value 0.404 |
ρ −0.778; p-value < 0.001* |
ρ −0.203; p-value 0.451 |
| Total OPs |
ρ −0.407; p-value 0.118 |
ρ −0.637; p-value 0.008* |
ρ −0.765; p-value 0.001* |
ρ −0.752; p-value 0.001* |
Statistical analysis: SPSS. Sample size for each pairwise comparison: 16 (i.e., 16 sampling events for each CDWDS). Unit for total chlorine residual concentration: mg Cl2·L−1. Unit for OP concentrations: log10(GCN·L−1). GCN: Gene copy number or genome copy number. ρ: Pearson (product-moment) correlation coefficient (i.e., Pearson’s r). p-value: Two-tailed.
*:
Significant correlation (i.e., p < 0.05).