Seasonal variations in the physico-chemical parameters of Lake Ribadu, Adamawa state Nigeria

Abstract

The assessment of seasonal variation of the physico-chemical quality of Lake Ribadu, Adamawa State Northeastern Nigeria was investigated. The water samples were collected bi-monthly from June, 2015 to May, 2016 for the physico-chemical parameters. The water temperature, pH, conductivity and total dissolved solids, transparency were measured in-situ with the use of Mercury in glass thermometer, water testing kits and secchi disk respectively. The dissolved oxygen and biochemical oxygen demand were measured ex-situ in the laboratory using Winkler’s method. The results showed variation in the water parameters within the months. The mean water temperature varied from 220C in January to 280C in April while the mean pH varied between 6.89 in July to 8.08 in January. The mean dissolved oxygen varied between 4.23mg/l in May to 6.89 mg/l in January while the biochemical oxygen demand varied between 2.17 mg/l in May and 3.91 mg/l in February. The lowest mean Conductivity was observed in August (391µmhos/cm) and the highest in April (480µmhos/cm) while the total dissolved solid was lower in August with the mean value of 343.7mg/l and highest in January (364.2mg/l). The correlation coefficient (r) showed high positive correlation between the water temperature and transparency (0.8732) and while water temperature and dissolved oxygen were negatively correlated (-0.8143). The results of all the physico-chemical parameters measured in Lake Ribadu are within the recommended limits of national and international standards; hence, support aquatic livings.