Physicochemical aspects and phytoplankton of the river shitalakhya receiving pharmaceutical effluents

Abstract

Phytoplankton from a part of the Shitalakhya river receiving effluents from a pharmaceutical industry have been studied. A total of 78 taxa were identified of which 14 belonged to Cyanophyceae, 11 Chlorophyceae, 20 Euglenophyceae and 33 Bacillariophyceae. The water body was mostly alkaline (6.6 - 8.0) and showed a wide range of variation in conductivity (135 - 4768 |iS/cm), DO (anoxia to 15 mg/1), free- C02 (3 - 29 mg/1), bicarbonate alkalinity (49 - 355 mg/1), BOD (8 -1800 mg/1) at different locations. Pharmaceutical effluents appeared to affect diversity of phytoplankton. Three diatoms namely Fragilaria brevistriata Grun., F. construens (Ehr.) Grun. and Navicula oblonga Kiitz. present in the area, are described as new for Bangladesh.