Classification scheme | Categories | Range (mg/L) | Number of samples | |||
Hand Dug Well (Wet Season) | Hand Dug Well (Dry season) | Borehole (Wet Season) | Borehole (Dry season) | |||
Sodium adsorption ratio (SAR) | Excellent | <10 | 15 | 15 | 15 | 15 |
Good | >10 - 18 | Nil | Nil | Nil | Nil | |
Fair | >18 - 26 | Nil | Nil | Nil | Nil | |
Poor | >26 | Nil | Nil | Nil | Nil | |
Hard | >200 - 300 | Nil | Nil | Nil | Nil | |
Very hard | >300 | Nil | Nil | Nil | Nil | |
Sodium Percentage (Na%) | Excellent | <20 | Nil | Nil | 15 | 15 |
Good | >20 - 40 | 5 | 3 | Nil | Nil | |
Permissible | >40 - 60 | 7 | 7 | Nil | Nil | |
Doubtful | >60 - 80 | 3 | 5 | Nil | Nil | |
Unsuitable | >80 | Nil | Nil | Nil | Nil | |
Magnesium adsorption ratio (MAR) | Acceptable | <50 | 13 | 14 | Nil | Nil |
Non-acceptable | >50 | 2 | 1 | 15 | 15 | |
Kelly’s ratio (KR) | Suitable | <1 | 15 | 15 | Nil | Nil |
Unsuitable | >1 | Nil | Nil | 15 | 15 | |
Potential soil salinity (PS) | Excellent to good | <5 | 15 | 15 | 15 | 15 |
Good to injurious | >5 - 10 | Nil | Nil | Nil | Nil | |
Injurious to Unsatisfactory | >10 | Nil | Nil | Nil | Nil |