Naukuchiatal is the deepest lake with an area of around 44.5 ha in Nainital, Uttarakhand. It houses a unique biodiversity. Along with Sattal and Bhimtal, this lakeis being used traditionally as primary source of drinking and irrigation water. This lake iscurrently under restoration with funds provided by the National Lake Conservation Plan(NLCP) of the Government of India Aeration of Lake Naukuchiatalis being carried out since 07 May 2015, with the aim to improve the overall lake ecosystem.In the present study, the artificially aerated Lake Naukuchiatal was selected to study various physico-chemical parameters. Such as DO, temperature, CO2, alkalinity, pH, TDS and transparency. Monthly samples were collected for water quality analysis for period of 6 months from May 2018 to October 2018. In Naukuchiatal lake maximum value was found in May i.e. 10.5 mg/l while minimum value was recorded in September i.e. 6.5 mg/l. This is due to aeration set up in Naukuchiatal in September 2015 Lake and cloudy weather decreases the level DO in water.
In Naukuchiatal Lake maximum value was found in June i.e. 25.3 °C , whereas minimum value was in July and October i.e. 24.2°C and 24.3 °C due to change in atmosphere changes the surface temperature of water.. Maximum free CO2 was 3.4 mg/l in month of September and minimum was 1.1 mg/l in month of May in Naukuchiatal Lake. As free CO2 observed higher in rainy season this was due to cloudy condition in upland areas leading to reducing the photosynthetic activity leading to higher respiration of organism in water thereby decreasing DO and increasing CO2. Maximum value of alkalinity was 140 mg/l and minimum was 110 mg/l in May in Naukuchiatal Lake. Increase in alkalinity is generally due to increase in bicarbonates and carbonate ions in water. The maximum value was 8.1 in September and minimum was 7.6 in June in Naukuchiatal Lake. Rainfall increases alkaline condition leading to increase in pH in water. The maximum value recorded was 113 mg/l in August and minimum was 90 mg/l in June in Naukuchiatal Lake.Maximum value was 140 cm in May and minimum was 118 cm in August in Naukuchiatal Lake. Monsoon brings high level of solids and agricultural runoff reducing transparency of water.
ACKNOWLEDGEMENT
The Author Mr Sagar Kuveskar is thankful to DES, Dean CFSc and Advisor GBPUA&T for providing all technical instrument and support. The author is also thankful to ICAR for providing financial assistance.