Biomonitoring of river Ganga bank by identifying mollusc species as an indicator

The present study deals with biomonitoring to know mollusc species as an indicator. In the present study, presence, absence and abundance of particular gastropod and bivalve species were identified in the different banks of river Ganga. The study was carried out at two experimental sites, Sodepur (Exp-1) and Khardah (Exp-2), West Bengal, India as the area exhibits a major sewage water outfall in the river compared with upstream control site, Kalyani (Cont-1) and downstream control site, Batanagar (Cont-1). The present biomonitoring shows qualitatively and quantitatively that in experimental no mollusc species were observed near the wastewater discharge area into the bank of river Ganga at Khardah while both sites of the sewage discharge area into the bank of river Ganga at Sodepur particular gastropod Bellamya sp. were observed when compared to control area. The highest variety and total nos of gastropods and bivalves (280 nos) were recorded in the upstream at Kalyani and lowest variety and total nos of only gastropods (150 nos) were recorded in the downstream at Batanagar. The present biomonitoring work was a preliminary observation to know sensitive and tolerant or accumulator mollusc species in the bank of river Ganga from a stretch of Kalyani (upstream) to Batanagar (downstream) in between urban wastewater discharge area (Sodepur and Khardah). Further researches must be relevant in relation to biomarker assessment with the physico-chemical factors and stress tolerant detoxification mechanism of particular mollusc species.