Physico-Chemical Characteristics and Phytoplankton Abundance of the Lower Niger River, Kogi State, Nigeria

Abstract

The River Niger serves a multitude of purposes for the Nigerian populace. It is a source of drinking water, hydro-electric power generation, irrigation, transportation and fishing other uses. A segment of the lower Niger River was surveyed for physico-chemical characteristics of water and phytoplankton abundance during two (2) months of dry season and two (2) months of wet season using standard methods. In the five sampling stations surveyed, Surface Water Temperature, Turbidity, Dissolved Oxygen, PO 4 -P and pH did not statistically significantly vary between the stations (P>0.05), whereas BOD and NO 3 -N varied statistically significantly between the stations (P<0.05). Phytoplankton abundance showed the following order of abundance: Bacillariophyta > Cholorophyta > Cyanophyta > Chrysophyta > Pyrrophyta. Based on Shannon-Weiner diversity index, the water in the 5 stations surveyed is classified to be moderately polluted. The results of this survey has shown that the multitude of users of the Lower Niger River have negatively impacted its water quality.