Table 3 Means and ANOVA data for water quality parameters among the lake site groups in 2015 and 2022.
Parameter | 2015 | 2022 | North 2022 vs North 2015 | Middle 2022 vs Middle 2015 | South 2022 vs South 2015 | |||||
|---|---|---|---|---|---|---|---|---|---|---|
North | Middle | South | North | Middle | South | P value | ||||
Transparency cm | 31.00 b | 43.75 a | 24.50 c | 40.50 ab | 57.50 a | 30.50 b | < 0.0001 | 0.000 | 0.072 | |
EC mS cm−1 | 17.06 a | 5.73 b | 3.08 b | 23.76 a | 18.55 a | 4.93 b | < 0.0001 | 0.001 | 0.661 | |
Salinity ‰ | 11.95 a | 4.01 b | 2.15 b | 16.63 a | 12.98 a | 3.45 b | 0.000 | 0.001 | 0.661 | |
pH | 8.62 a | 8.35 ab | 7.95 b | 8.65 a | 8.61 a | 8.02 b | 0.119 | 0.589 | 0.171 | |
DO mg L−1 | 8.13 a | 5.89 ab | 3.26 b | 9.21 a | 6.81 ab | 4.77 b | 0.086 | 0.097 | 0.009 | |
BOD mg L−1 | 14.57 b | 14.86 b | 49.97a | 9.74 b | 9.99 b | 19.85 a | 0.000 | 0.004 | 0.018 | |
COD mg L−1 | 30.15 b | 28.96 b | 103.43 a | 22.18 b | 21.49 b | 87.11 a | < 0.0001 | 0.002 | < 0.0001 | |
NO2–N µg L−1 | 77.23 b | 71.81 b | 139.61a | 100.41 a | 62.69 b | 85.68 b | < 0.0001 | 0.001 | 0.026 | |
NO3–N µg L−1 | 319.53a | 261.22 a | 389.70 a | 209.42 a | 212.23a | 199.88 a | < 0.0001 | < 0.0001 | 0.180 | |
NH4–N µg L−1 | 0.878 b | 0.595 b | 6.07 a | 0.67 ab | 0.37 b | 4.68 a | 0.001 | 0.657 | 0.000 | |
PO4–P µg L−1 | 137.70 b | 155.09ab | 423.85a | 79.41a | 76.16 b | 246.53 a | < 0.0001 | < 0.0001 | 0.003 | |
TN mg L−1 | 1.827 b | 1.413 b | 9.422 a | 1.406 b | 0.977 b | 7.106 a | 0.001 | 0.330 | 0.000 | |
TP µg L−1 | 268.07b | 298.47 b | 733.20a | 216.27b | 226.61b | 601.13 a | < 0.0001 | < 0.0001 | 0.017 | |
