Research Article
E-J.Chem ,
Volume 5,
Number 2,
Study on the Quality of Water in
Some Streams of Cauvery River
ABIDA BEGUM and HARIKRISHNA
Department of Chemistry, P.E.S School of Engineering, Bangalore- 560 100
Shirdi Sai Engg. College, Bangalore. Visveshwaraya Technological University, Belgaum,
ABSTRACT
The
quality of water in four streams of Cauvery River in Mandya District, where many small
scale sugar and brewery distilleries are located, was analysed. Sampling was
carried out from four streams designated as station 1 (upstream of effluent
discharge point), station 2 (effluent discharge point) and station 3 (downstream
of effluent discharge) station 4 (fresh water stream) to assess the impact of
effluent on the water quality. The river water composition is increasingly
dominated by Na and Cl in the downstream region of the river, indicating the
influence of airborne salts with oceanic affinities. Significant spatial
variation was observed in water level, transparency, turbidity, depth, dissolved
oxygen, colour, biochemical oxygen demand, nitrate, nitrite and total
hydrocarbon among the physiochemical parameters of the study stations. A
posteriori test revealed that station 2 & 3 were the cause of the
significant difference. The dissolved oxygen level in stations 2 & 3 was
lower than 5.0mg/L, which is recommended minimum allowable limit for aquatic
life. About 7 rotifer species in large amount recorded in this study were
encountered in station 1, 7 in station 2 & 3 while 12 species in station 4.
The overall density of rotifers in the four stations was significantly
different. A posteriori
comparison revealed that station 2 & 3 are the cause of the significant
difference. The Branchionus angularis rotifers, which dominated the community,
were found to tolerate the effluent effect in station 2&3, and showed
remarkable recovery in the downstream station 4. Low faunal diversity and
negative impact on the biotic and abiotic environment was experienced in station
2 & 3 throughout the duration of sampling because of the brewery effluent
discharged directly into these two Streams