Assessment of Plankton Diversity in Relation to Water Quality Variables of Musgola Fish Farm at Lapai - Gwari, Minna, Niger State, Nigeria

Abstract

This study was carried out to determine the plankton interaction with the physico-chemical parameters of four earthen fish ponds in Musgola Fish Farm Minna, Niger state. The study was conducted from March to June; 2021. Samples of Water were analyzed using standard methods. One-way analysis of variance with Duncan multiple tests was used to analyze the water quality parameters. PAST (Multivariate: Canonical correspondence analysis) was used to evaluate relationship between plankton communities and environmental variables. Physico-chemical Parameters determined include: Biochemical Oxygen Demand, Alkalinity, Dissolve Oxygen, Nitrate (NO3), Phosphate (PO4), Sodium(Na),potassium(k), Electricalconductivity, Air temperature and potential hydrogen. There was no significant temporal variation in physico-chemical variables. However, there were slightly change in parameters throughout the study period. The study revealed thatzooplanktons were dominated by Cladocera species (MoinaMicrura) with (43.02%), followed by Copepod (Cydopoid copepods) with (26.99%) and Rotifers (Brachionuscalyciflorus)representing7.45%.The abundance of zooplankton observed in this study can be attributed to the anthropogenic perturbations on-going in and around the Fish farm as well as the farmed fish. Moreover, the presence of suitable zooplankton species is essential for successful farming. Similarly, seventeen species of phytoplankton were identified,including Bacillariophytes, Chlorophytes and cyanophytes. Chlorella species of the class Chlorophyceae was the most prevalent group in the four ponds over Bacillariophyceae and Cyanophyceae.Canonical correspondence Analysis revealed that physico-chemical variables have positive influence on the composition and diversityof plankton in earthen fish ponds at Mosgola Fish Farm. The plankton community, on which the whole aquatic population depends, is largely affected by an interaction of a number of limiting factors such as, moderate sulphate,nitrate, phosphate and other factors. Variations of the physical and chemical parameters in a fish pond showed that the limnological conditions in the fish pond are not spatially homogenous.Thus, water quality management in the fish pond expressed direct influence on planktonic population, since fish ponds are shallow and constantly receive large nutrient loads (feed, fertilizing, and fish waste).