MACROINVERTEBRATE DIVERSITY OF EFFLUENT AFFECTED DHANSIRI AND KALIANI RIVERS OF ASSAM, INDIAJanmoni Moran
A survey of macroinvertebrate diversity was carried out for two years in the two rivers of Assam â Dhansiri and Kaliani of Golaghat district which were used as basin to discharge the effluent from the Numaligarh Refinery. The rivers sections were divided into two areas- control area and contaminated area for comparison. The two rivers experienced a change in the occurrence and abundance of the macroinvertebrate community. A total no. of 23 genera and 2 tribes (Chironomidae family) belonging to 25 families of macroinvertebrates have been recorded belonging to 10 orders, 4 classes and 3 phyla. The point of effluent discharge harbored only 8 families indicating an adverse effect from the refinery effluent.