Physicochemical Characteristics and Plankton Diversity of Lagos Lagoon and its Adjoining Abule-Agege and Abule-Eledu Tidal Creeks, Lagos State, Nigeria

Abstract

Plankton have great ecological importance as they fix carbon dioxide, produce oxygen, and serve as autotrophs at the base of various food chains in the different aquatic environments worldwide. Hence, the objective of this paper was to investigate the physicochemical characteristics and plankton diversity of Lagos Lagoon and its adjoining Abule-Agege and Abule-Eledu Tidal Creeks, Lagos State, Nigeria using appropriate standard techniques. Result of the physicochemical conditions varied from fresh through low to high brackish water conditions at the study locations. Thirty-five (35) taxa belonging to 21 genera were observed for the phytoplankton. The blue-green algae recorded 2 species from 2 Orders (5.71 %), while the diatoms are the more abundant group with a total of 33 taxa from 2 Orders (94.29 %). Zooplankton forms recorded a total of 17 taxa belonging to 14 genera from three main groups. Arthropods were the most abundant group with 13 taxa from 3 classes (52 %), while the Rotifers made up 4 species from 4 genera (16 %) and 5 Juvenile stages (32 %) respectively. Notable phytoplankton species reported were Microcystis aeruginosa, Oscillatoria sp., Synedra crystallina, and the zooplankton species were Paracalanus parvus, Enterpina acutifrons, Cyclops strenus, Daphnia magma, Keratella cochlearis, Baranacle nauplii, Gastropod and Polychaetes larva. Importantly as salinity increased, the diversity of plankton form groups increased in these ecosystems.