Assessment of Physicochemical Parameters of Lonar Lake Water for Environmental Monitoring

Abstract

The present study investigates the temporal and spatial variation in key physicochemical parameters of Lonar Lake, a unique saline and alkaline crater lake located in Maharashtra, India. Monthly monitoring was conducted from January to October 2022 across four designated sites (S1–S4). Parameters analyzed included temperature, pH, turbidity, total hardness, total alkalinity, chloride, residual chlorine, nitrate, phosphate, and sulphate. The results revealed consistently alkaline conditions (pH 10.0–10.5) and high total alkalinity (2266–3432 mg/L), reaffirming the soda lake characteristics of Lonar. Temperature ranged from 23°C to 31°C, with higher values during pre-monsoon and monsoon seasons. Chloride and residual chlorine concentrations were notably high, with peaks of 1876 mg/L and 5168.6 µg/L, respectively, suggesting evaporative enrichment and possible microbial contributions. Nutrient levels, including nitrate (2.1–6.3 mg/L) and phosphate (0.34–0.54 mg/L), indicated moderate eutrophication potential. Sulphate and hardness values showed moderate variation, influenced by geological and hydrological factors. These findings are in line with previous research, highlighting the lake’s stable but extreme physicochemical environment that supports specialized microbial communities. Continuous monitoring of such parameters is essential for understanding ecological dynamics, microbial diversity, and the conservation needs of this geologically significant ecosystem.