Douala | Yaoundé | |||||||
---|---|---|---|---|---|---|---|---|
Cultivated areas | Non Polluted | Polluted | P value | Cultivated areas | Non Polluted | Polluted | P value | |
N | 12 | 68 | 50 | 53 | 54 | 41 | ||
Alcalinity | 35.3 ± 11.1 | 117.3 ± 3.8 | 125.2 ± 5.84 | 0.1 | 136.9 ± 5.6 | 184.7 ± 5 | 201.1 ± 6.9 | 0.09 |
Conductivity | 192.4 ± 24.8 | 294.9 ± 3.7 | 505.7 ± 9.6 | 0.000 | 608.8 ± 28.4 | 705.8 ± 24.2 | 1188.3 ± 44.8 | 0.005 |
Turbidity | 127 ± 38.1 | 73.4 ± 4.2 | 146 ± 7.7 | 0.000 | 93.98 ± 5 | 78.2 ± 3.9 | 148.2 ± 8.4 | 0.05 |
pH | 5.89 ± 0.2 | 6.61 ± 0.02 | 6.77 ± 0.12 | 0.12 | 6.46 ± 0.05 | 7.04 ± 0.04 | 6.96 ± 0.05 | 0.07 |
Temperature | 29.9 ± 0.4 | 29.6 ± 0.06 | 30.2 ± 0.1 | 0.60 | 28.69 ± 0.18 | 27.93 ± 0.1 | 27.7 ± 0.13 | 0.30 |
Ammonia | 1.03 ± 0.4 | 1.02 ± 0.05 | 1.03 ± 0.07 | 0.06 | 1.84 ± 0.1 | 1.83 ± 0.09 | 2.4 ± 0.1 | 0.4 |
Nitrates | 4.8 ± 1.2 | 4.01 ± 0.2 | 7.42 ± 0.5 | 0.29 | 2.7 ± 0.09 | 3,53 ± 0.18 | 4.02 ± 0.21 | 0.28 |
Nitrites | 0.05 ± 0.01 | 0.5 ± 0.05 | 0.07 ± 0.007 | 0.68 | 0.26 ± 0.02 | 0.22 ± 0.01 | 0.37 ± 0.03 | 0.49 |
Aluminium | 0.96 ± 0.3 | 0.124 ± 0.01 | 1.4 ± 0.14 | 0.08 | 0.01 ± 0.0006 | 0.045 ± 0.003 | 0.032 ± 0.004 | 0.03 |
Manganese | 73.5 ± 27 | 6.8 ± 1.6 | 55.2 ± 4.8 | 0.19 | 0.012 ± 0.0007 | 0.013 ± 0.0005 | 0.007 ± 0.0004 | 0.14 |
Phosphate | 0.99 ± 0.3 | 0.67 ± 0.05 | 0.69 ± 0.14 | 0.025 | 1.12 ± 0.04 | 0.60 ± 0.075 | 1.1 ± 0.05 | 0.03 |
Sulfate | 27.7 ± 5.7 | 24.8 ± 1.03 | 36.8 ± 2 | 0.67 | 16.3 ± 1 | 45.78 ± 1.4 | 38.4 ± 2.2 | 0.001 |
Mg Hardness | 10.2 ± 2.6 | 24.3 ± 1.6 | 9.4 ± 1.03 | 0.06 | 16 ± 1.9 | 24.07 ± 3.4 | 21.9 ± 3 | 0.46 |
Total hardness | 20 ± 4.5 | 57.4 ± 1.9 | 60.6 ± 3.4 | 0.37 | 94 ± 3.5 | 116.7 ± 3.6 | 125.6 ± 3.8 | 0.06 |
Magnesium | 1.67 ± 1.9 | 3.04 ± 0.56 | 0.6 ± 0.3 | 0.18 | 22.4 ± 2.4 | 23.3 ± 1.7 | 24.7 ± 2 | 0.97 |
Iron | - | 12.9 ± 1.4 | 23.2 ± 6.4 | 0.16 | 3.2 ± 0.3 | 5.4 ± 0.4 | 3.8 ± 0.4 | 0.11 |
Potassium | - | 8.6 ± 0.69 | 21.5 ± 3.5 | 0.03 | 13.4 ± 2.4 | 7.8 ± 0.6 | 18.3 ± 2.2 | 0.05 |
Dissolve oxygen | - | 89.9 ± 6.5 | 360.9 ± 309 | 0.31 | 122.9 ± 9.2 | 85.8 ± 2.8 | 84.3 ± 0.9 | 0.17 |