Assessment of Physico-Chemical Parameters and Zooplankton Diversity in Tripuranth Lake, Basavakalyan, Bidar District, Karnataka

Tripuranth Lake is a critical freshwater resource supporting irrigation, aquaculture, domestic use, and local biodiversity. This study examines monthly variations in physico-chemical parameters and zooplankton diversity from January 2024 to December 2024 to evaluate the lake’s water quality and ecological health. Key physico-chemical parameters, including atmospheric temperature, water temperature, pH, dissolved oxygen (DO), total dissolved solids (TDS), conductivity, total alkalinity, total hardness, calcium (Ca²⁺), and magnesium (Mg²⁺), were analyzed. Zooplankton sampling identified 31 species across four groups: Rotifera (12 species), Cladocera (9 species), Copepoda (7 species), and Ostracoda (3 species), with Rotifera being dominant. Strong correlations were observed between physico-chemical parameters and zooplankton abundance, particularly with temperature (r > 0.8) and DO (r > 0.7), driving higher zooplankton density in warmer, oxygen-rich pre-monsoon months (April–June) due to enhanced nutrient availability and phytoplankton growth. Seasonal fluctuations showed peaks in temperature, pH, TDS, and DO during pre-monsoon, influenced by evaporation, agricultural runoff, and photosynthetic activity, which positively correlated with zooplankton peaks. Similar patterns were noted in nearby Khajikotnoor Reservoir, where physico-chemical parameters like temperature and nutrient levels correlated with zooplankton density (Patil et al., 2025).