Dry Season Phytoplankton Composition Of Ibiekuma Dam, Ekpoma, Edo State

Abstract

In this study, the phytoplankton composition of Ibiekuma dam, Ekpoma was investigated between January and February, 2010. A total of 20 phytoplankton taxa belonging to three divisions; Bacillariophyta, Chlorophyta and Euglenophyta were observed. All the species of Bacillariophyta observed were pennate forms. Only Surirella elegans was observed in the three areas studied in the dam while Synedra acus,was observed in SW2 (inside dam) and Pinnularia viridis in SW3(downstream of dam). The taxa was dominated qualitatively by green algae(desmids).SW2 accounted for most of the desmids encountered. Generally the division Chlorophyta had the highest percentage composition (55%), followed by Bacillariophyta (40%) and Euglenophyta (5%). In the physico-chemical parameters studied, temperature fluctuated between a mean of 27.25°C (SW3) to 28.75°C (SW1 and SW2). pH values of the three areas studied had a mean range of 6.41 to 7.01 and there was slight variation in mean conductivity values (SW1, 31.53μScm-1; SW2, 30.58μScm-1; SW3, 30.15μScm-1). Total dissolved solids ranged from 14.9mgl-1 (SW3) to 15.28mgl-1 (SW1).

Key words: Phytoplankton, Ibiekuma, dam, taxa, desmids