EN
The physicochemical and epipelic algal analyses in the catchment of lower Bonny river, Nigeria, was carried out between September 1998 and February 1999. A total of 51 species were observed of which Bacillariophyceae had 28 species followed by Cyanophyceae (19 species), Chlorophyceae (2 species), and Euglenophyceae (2 species), respectively. The epipelic algal abundance ranged from 3.2 ± 0.8 × 108 indiv, cm⁻² to 6.3 ± 0.6 × 108 indiv, cm⁻² in wet season and 3.9 ± 0.3 × 108 indiv, cm⁻² to 6.9 ± 0.6 × 108 indiv. cm⁻² in dry season. In addition, chlorophyll a values range from 0.85 ± 0.15 to 2.61 ± 0.42 mg cm⁻² m wet season and 1.02 ± 0.12 to 4.45 ± 0.88 mg cm⁻² in dry seasons, respectively. This range of variation was relatively narrow and the whole community seems to be persistent and stable during wet and dry seasons.