STUDIES ON THE CAUSATIVE GENERA OF PHYTOPLANKTON BLOOM IN FISH PONDS OF MYMENSINGH

Abstract

A study on the causative genera of phytoplankton bloom was carried out in six fish ponds in and around Bangladesh Agricultural University campus. Of the total 38 genera of phytoplankton, seven genera belonging to Bacillariophyceae, 21 to Chlorophyceae, eight to Cyanophyceae and two to Euglenophyceae were recorded during the study among which Microcystis was dominant followed by Chlorella, Euglena, Anabaena and then Melosira. The bloom was formed by Microcystis and Anabaena during the study. There was almost inverse correlation of Microcystis and Anabaena with other genera found in almost all the ponds. Microcystis had direct correlation with Anabaena in all the ponds except pond 6. The correlation values of Microcystis and Anabaena with other genera indicate that these two genera might have growth inhibitory effect on other genera.