Freshwater diatoms diversity of national parks in Nigeria I: Okomu national park, South-South, Nigeria

Abstract

This study represents the first taxonomic and ecological description of the diatom flora of water and sediments in two freshwater lakes within Okomu National Park Edo State, Nigeria, using light and scanning electron microscopy (SEM). Twenty-nine species of diatoms belonging to fifteen genera, Achnanthes, Achnanthidium, Chamaepinnularia, Cymbella, Discotella, Eolimna, Eunotia, Frustulia, Gomphonema, Luticola, Nitzschia, Pinnularia, Placoneis Sellaphora and Stauroneis were identified. The taxa were dominated by Eunotia spp. Water pH of 5.9-6.3  and surface temperature of 28 ^oC probably implies that the diatoms especially Eunotia spp are exploring an ecological niche that is probably favourable for its growth. Okomu National Park appears to be a hotspot for Eunotia species diversity, and further study of the oligotrophic waters of this site is recommended.

Keywords: Diatom, Diversity. Freshwater, National Park, Okomu, Season, Tropical.