Table 3.
Minimum (Min), Maximum (Max), average, and standard deviation (SD) of physico- chemical parameters measured during the present study and used to evaluate: trophic state index (TSI); trophic level index (TLI) and water quality index (WQI) of the Lake Timsah.
| Parameter | Min | Max | Average | SD |
|---|---|---|---|---|
| Secchi disc transparency (m)a, b | 0.5 | 2 | 1 | ±0.30 |
| Temperature (°C) | 16 | 30 | 22 | ±2.40 |
| Salinity (‰) | 17 | 40 | 36 | ±4.80 |
| pHc | 7.8 | 8.4 | 8.2 | ±0.01 |
| Total Phosphorusa, b (µg l−1) | 24 | 96 | 48 | ±7.00 |
| Total Nitrogenb (µg l−1) | 430 | 780 | 720 | ±76.8 |
| Chlorophyll aa, b (µg l−1) | 6.5 | 56 | 20 | ±5.70 |
| TN/TP ratio | 15.5 | 16.7 | 16 | ±4.30 |
| Phosphatec (µM) | 63.6 | 85.2 | 81.4 | ±6.20 |
| Nitratec (µM) | 6.7 | 17.8 | 9.75 | ±5.40 |
| Silicatec (µM) | 1.4 | 4.1 | 3.4 | ±0.70 |
| Ammoniac (µM) | 0.2 | 1.2 | 0.8 | ±0.10 |
| Dissolved oxygenc (mg l−1) | 6.5 | 12.2 | 9.4 | ±3.00 |
| Nitritec (µM) | 0.08 | 0.8 | 0.6 | ±0.03 |
| TSI | 50 | 70 | 60 | ±9.30 |
| TLI | 4.1 | 6.3 | 5.2 | ±0.87 |
| WQI | 27 | 67 | 49 | ±8.83 |
a
Measured parameters used for calculating TSI.
b
Measured parameters used for calculating TLI.
c
Measured parameters used for calculating WQI.