Variability in water quality and phytoplankton community during dry and wet periods in the tropical wetland, Bhopal, India
The Bhoj wetland, a Ramsar site has been found to be under huge pressure due to burgeoning human population in its catchment area. The present investigation spread across nine stations has revealed higher algal diversity (294 species) during the period of 2008-2009. The phytoplankton diversity belonging to six groups revealed 46% contribution of Chlorophyceae followed by Bacillariophyceae (28%), Cyanophyceae (15%), Euglenophyceae (9%), while Pyrophyceae and Chrysophyceae contributed 1% each, respectively. Closterium sp., Cosmarium sp., Pediastrum sp., Scenedesmus sp., Staurastrum sp. and Tetraedron sp. contributed the bulk of Chlorophyceae was dominated by these various species and from Bacillariophyceae was mostly represented by Achnanthes sp., Cymbella sp., Navicula sp., Gomphonema sp. and Synedra sp. Cyanophyceae was represented by Anabaen sp., Aphanocapsa sp. and Oscillatoria sp., Aphanocapsa sp., Microcystis sp. and Oscillatoria sp. Species like Euglena sp. and Phacus sp. represented euglenophyceae. The higher abundance of (Closterium, Pediastrum, Scenedesmus, Navicula, Anabaena, Microcystis and Phacus) and nutrient concentration (nitrate-nitrogen and phosphorus) during the dry and wet periods reflect higher organic pollution in the Bhoj wetland. There should be strict legislation to protect the wetland from undue exploitation.