WATER QUALITY AND ALGAL BIODIVERSITY OF EBONYI RIVER, UDENU L.G.A, ENUGU STATE, NIGERIA.
The physico-chemical and algal characteristics of the upper reaches of Ebonyi River were studied in four stations over a four- month period from September to December 2014. The physico-chemical parameters: air and water temperatures, colour, depth, rate of flow, transparency, pH, Total Dissolved Solids (TDS), alkalinity, Biochemical Oxygen Demand (BOD5), Dissolved oxygen (D.O), silica, potassium, phosphate, nitrate, chlomride, calcium, lead, iron and mercury were studied using standard methods. Parameters such as colour, calcium, pH, total dissolved solids, alkalinity, chloride, dissolved oxygen, silica, biochemical oxygen demand, phosphate, nitrate, potassium and lead did not significantly differ between the locations (P ≤ 0.05). Air temperature, depth, rate of flow and transparency differed significantly between locations. All parameters differed significantly between months except depth and rate of flow which did not significantly differ between the months. Mercury was not detected during the study period. A total of twenty nine (29) taxa of algae were observed in the study. Algal abundance showed the following order: Heterokontophyta > Chlorophyta > Cyanophyta > Euglenophyta > Cryptophyta. Based on Shannon-Wiener diversity index, the water in the four locations studied is moderately polluted. The study revealed that though Ebonyi River is not heavily polluted, the fluctuations of the investigated parameters along the sampling points could be as a result of both anthropogenic and natural activities.