Evaluation of Various Physicochemical Properties and Their Seasonal Variation in Wulur Lake of Kashmir Himalayas

This study aimed to evaluate the water quality of Wulur Lake, the largest freshwater lake on the Indian subcontinent, taking into account spatiotemporal fluctuations in physicochemical parameters. The water samples were taken from five locations (Makhdomyari, Vintage, Ashtang, Matlab, and Ningle) for 3 years, viz., 2019, 2020, and 2021. The results of various physiochemical parameters during the entire study showed that the water quality of Wulur Lake has deteriorated due to the increased growth of macrophytes. The correlation analysis found significant positive and negative correlations between the studied parameters: temperature, depth, transparency, pH, conductivity, dissolved oxygen (D.O.), chloride, total alkalinity, hardness, calcium, nitrogen, phosphorus, and magnesium content. The principal component analysis (P.C.A.) demonstrated the most excellent match among the various physiochemical parameters, with two principal components explaining 63.5%, 63.8%, and 64.1% of the observed data variability in the sampling years 2019, 2020, and 2021 respectively. The Lake is becoming eutrophic, as evidenced by the low D.O. levels, increased nitrate-nitrogen and total phosphorus, high magnesium values, conductivity, total alkalinity, hardness, and calcium hardness. The Lake will likely continue to worsen and eventually become eutrophic if proper conservation measures are not implemented.