PHYTOPLANKTON ASSEMBLAGE AND PHYSICOCHEMICAL PARAMETERS OF A PERTURBED TROPICAL MANMADE LAKE, SOUTHWESTERN NIGERIA.
This study identified the phytoplankton assemblage of the Dandaru Lake (that received effluents from a zoological garden and hospital) as bioindicators of water quality. Samples of water and plankton were collected from April to September, 2015 at five stations (I – V). The mean physicochemical parameters were within the limits of USEPA except Lead, 0.02 ± 0.08 mg/ L; Manganese, 0.46 ± 1.00 mg/ L and Zinc, 0.05 ± 0.17 mg/ L. The highest mean DO (6.88 ± 1.34 mg/L) was recorded in station I with less anthropogenic activities, highest phosphate concentration (0.28 ± 0.28 mg/L) occurred in station II, the entry point of wastewater from hospital and zoological garden. The order of abundance for phytoplankton was Euglenophyceae (49.77%) > Bacillariophyceae (18.00%) > Cyanophyceae (17.39%) > Chlorophyceae (13.7%) > Xanthophyceae (1.06%) > Chrysophyceae(0.02%). The stations impacted with effluents were dominated by members of Euglenophyceae and Cyanophyceae. While station I was dominated by diatoms (57.98%). The species richness recorded was 0.32 – 4.49. The phytoplankton assemblage and comparatively low biotic diversity in Dandaru Lake could be attributed to perturbations in the water column that exerted selective effects on the biological assemblage
adedolapo ayoade (Primary Presenter/Author), University of Ibadan, firstname.lastname@example.org;