IJEP 44(10): 922-930 : Vol. 44 Issue. 10 (October 2024)
N.M. Guruprasad and S.H. Basavarajappa*
Kuvempu University, Department of Environmental Science, Shankaraghatta, Shivamogga – 577 203, Karnataka, India
Abstract
Riverine input is the major source of nutrients for the stable ecosystem of estuaries which may be altered by the construction of hydroelectric dams for human needs. aghanashini and sharavati are two west-flowing rivers emptying into the arabian sea on the central western coast of india. aghanashini is a free-flowing river that forms an estuary near the town of kumta and sharavati, which has hydroelectric dams upstream, forms an estuary near the town of honnavar. the present study investigated the physico-chemical parameters of aghanashini and sharavati estuaries for 12 months from july 2022 to june 2023 using standard laboratory methods. the present study compares seasonal variations in the water quality of the two estuaries. our studies revealed that aghanashini had significantly higher concentration of total dissolved solids, salinity, conductivity, turbidity, alkalinity, hardness, calcium, magnesium, potassium, sodium, phosphate, nitrate, chloride, organic matter and organic carbon than sharavati estuary. we found that the physico-chemical parameters of the estuaries were influenced by water discharges from the river. this study serves as a connecting bridge between the people and policymakers, revealing the importance of the riverine inputs in water quality and the formation of the estuarine ecosystem. the results provide a scientific basis for the long-term management of the ramsar site-aghanashini estuary.
Keywords
Damming, Ecosystem, Estuaries, Nutrients, Rivers, Salinity, Seasons, Water quality
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