Status of the River Krishna: Water quality and riverine environment in relation to fisheries

Abstract

The River Krishna, the second largest peninsular river of India, was investigated during pre-monsoon, monsoon, and post-monsoon seasons to improve the understanding of its ecology through analysis of physical and chemical parameters of water and sediment. Important tributaries of the river were also studied simultaneously to understand their influence on the main stream of the River Krishna. In addition to 25 sampling sites along the main stream of the River Krishna, sampling was also done in 13 important tributaries at sites upstream of the confluence point. Dams, barrages and anicuts have visible impacts on all of the observed physical and chemical properties of water and soil. Statistical analysis revealed that water parameters have a strong association with sediment parameters. However, the study was unable to find any relation between primary production and water quality parameters. Fish species distribution was strongly influenced by temperature and water depth, as well as specific conductivity, as observed through Canonical Correspondence Analysis.