Current Journal of Applied Science and Technology

Periphyton and phytoplankton communities were compared and investigated in view of the environmental conditions at Ejirin part of Epe lagoon, from Dec. 2012 – May, 2013. This was to evaluate the effect of the environmental characteristics on the biotic communities. Surface water temperature correlated significantly with rainfall (r 0.855*; P < 0.05), surface water Chl. a (r = 0.817*; P < 0.05) and with periphyton individual (r = 0.745). The water pH remained acidic throughout the study period (pH < 6.6) with a mean value of 6.39. Transparency values were high in the dry months and low in the wet months, with the strong significant correlation with the periphyton and phytoplankton individual (r =0.844*; P < 0.05) and (r = -0.887*; P < 0.05) respectively. Total suspended solids has a mean value of 61.02mg/L, and correlated significantly with periphyton individual (r=0.836*; P < 0.05), and strongly correlated with phytoplankton individual and rainfall (r =0.791 and 0.678) respectively. The micronutrients varied throughout the study periods with reactive nitrate (NO₃-N ≤ 0.32mg/L), reactive phosphate (PO₄-P ≤ 0.78mg/L), silicate (SiO₃ ≤ 0.80mg/L), and sulphate (≤1.30mg/L). Sulphate correlated strongly with phytoplankton and periphyton individual (r=0.616 and 0.707) respectively. Five divisions were recorded in phytoplankton community with their percentage of occurrence: Bacillariophyta (82.45%), Cyanobacteria (9.99%), Chlorophyta (6.08%), Euglenophyta (1.32%), and Chrysophyta (0.12%), whereas four divisions were recorded in periphyton community with their percentage occurrence: Bacillariophyta (82.67%), Cyanobacteria (10.54%), Chlorophyta (5.64%), and Euglenophyta (1.15%). The PCA factor analysis revealed the importance of the followings: water temperature, pH, TDS, rainfall, sulphate, COD, BOD, nitrate, phosphate, salinity and, phytoplankton and periphyton individual to the future environmental analysis. Therefore, the periphyton community has shown a more promising tool in the event of environmental studies by responding significantly to most of the environmental parameters studied.