Primary Productivity of Tripuranth Lake, Basavakalyan, Bidar District, Karnataka

The current study evaluated the primary productivity of Tripuranth Lake in Basavakalyan, Bidar District, Karnataka, from January 2024 to December 2024 to analyze seasonal changes in gross primary productivity (GPP), net primary productivity (NPP), and community respiration (CR). Water samples were gathered from four sampling locations, and primary productivity was assessed using the light-and-dark bottle technique (Gaarder and Gran, 1927). Results indicated a trimodal oscillation pattern in GPP, featuring peaks in the summer and northeast monsoon seasons. The annual average GPP varied between 0.45 to 1.25 mgC L⁻¹ day⁻¹, NPP between 0.20 to 0.75 mgC L⁻¹ day⁻¹, and CR from 0.15 to 0.60 mgC L⁻¹ day⁻¹. The lake shows a moderate to high level of primary productivity, ideal for improving aquaculture and fisheries. Productivity was affected by physico-chemical factors such as temperature, pH, dissolved oxygen, nutrient levels (nitrogen and phosphorus), and changes in seasonal water levels.