The hydrochemical study of Chitgar Lake

The man-made Lake of the Martyrs of the Persian Gulf (also known as the Chitgar Lake) is located in the northwestern of Tehran and was established in 2012 and field with Kan River water at the same year. The water quality was investigated on 5 sampling site during 2013-2014. Standard methods (APHA, 2005) were used for Analysis of water parameters. The results indicated that the mean monthly temperature of water was 18.4±7.3 °C. The mean monthly EC level was 373±30 µs/cm. The mean monthly total hardness, dissolved oxygen, total phosphorous, total nitrogen, silicate, respectively were 119±5, 7.8±1.2, 0.04±0.01, 2.06±0.41, 9.6±0.5, all as mg/l,. The mean chlorophyll-a was 1.6 ± 0.81 µg/l. All parameters showed no significant differences between stations (P>0.05), while total hardness, chlorophyll-a, Do, total phosphorus and silicate showed monthly significant differences with 95% confidence level. The ratio of total nitrogen to total phosphorus was 51 which indicated phosphorus is limiting factor in eutrophication process. According to Carlson trophic index determined to be oltraoligotroph (TSI<40). The result indicated that changes in nutrient concentration is under biological activity influence.