Abstract

There has been a serious concern about declining water quality in the rivers and streams since 1960. Wide varities of pollutants have been reported to cause deterioration of water quality in rivers. Tungabhadra River in Karnataka is an important tributary of Krishna. It has a drainage area of 71,417 sq. km out of which 57,671 sq. km area lies in the state of Karnataka. The river covers the distance of 293 km in the state. This river is considered as life line of this area, which fulfills the needs of hundreds of villages, situated at both sides of the river. The study was conducted to measure its various physico-chemical and bacteriological parameters including levels of algal community. Pollution in water bodies may indicate the environment of algal nutrients in water. They may also function as indicators of pollution. Hence, the present investigation is an attempt to know the pollution load through algal indicators in Tungabhadra river of Karnataka near Harihar town. The study has been conducted from May 2004 to April 2005. The water and algal samples were collected at regular intervals of 15 days at four stations for one year. The most tolerant genera and species of four groups of algae namely, Chlorophyceae, Bacilariophyceae, Cyanophyceae and Euglenophyceae indicate that total algal population is 17,7159 o/L in station S₃; which has the influence of industrial pollution from Harihar Polyfibre and Grasim industry situated on the bank of the river; which are discharging its treated effluent to this river. The population of algal species is 75,849 o/L at station S₁, 68,056 o/L station S₂ and 38,915 o/L station S₄. The correlation and inter correlation among the physico-chemical parameters along with phytoplankton groups have been made. The results obtained are tabulated and discussed.

Key words: Tungabhadra River, dynamics, phytoplankton, succession