水産および畜産生産

抽象的な

Seasonal Variation in Physicochemical Parameters on Fisheries of Ebonyi River System

Nwabunike MO

The study analyzed the seasonal variation in physicochemical parameters on fisheries of Ebonyi river system. The objectives of the study were to analyze the physiochemical properties of Ebonyi river system and its correlation and to make necessary recommendations for the general improvement of fish management in the study area. Multimesh gillnets were used to monitor the abundance and structure of the fish fauna. Stratified random sampling was carried out in each water body. The fishes were caught, identified, counted, graded, measured and weighed according to species. The species for chemical and histological analysis were taken immediately after weighing to the laboratory. Concentration of metals were studied in fish blood, liver and in the tissue lying between the lateral lines and the fins, since high concentrations of metals do not imply that the metal have a toxic effect (-). Toxicity of metals is mostly associated with vital physiological functions, such as enzyme activity, modifications in membrane, lipid composition and changes in tissue structures. It was observed that in dry season, water temperature of Mkpuma river and pond water were statistically similar (p > 0.05). However, their values differed significantly of those of Ameka Dam, Enyigba River and Ebonyi river. The pH in dry season across study areas was similar for Ameka Dam and Enyigba River and these were significantly higher (p < 0.05) than those of other study areas, which did not differ significantly (p > 0.05) among themselves. Mkpume river, Ebonyi river and Ameka Dam had statistically similar DO values (p > 0.05) while Enyigba and pond water had insignificantly different DO concentration (p > 0.05). The CO2 concentration in dry season was significantly higher in Mkpume river followed by Ameka dam but the CO2 of Ameka dam was not significantly different (p > 0.05) from those of Ebonyi river and pond water. Enyigba River had the least CO2 concentration. Water had it highest transparency in Enyigba river (p < 0.05) followed by those of Mkpume river, pond water, Ebonyi River and Ameka dam. It was also observed that during rainy season, water temperature in Mkpume river was significantly different (p < 0.05) from those of other study areas while the water temperature of Ameka Dam was the least. Mkpume river also had the highest pH value but it does not differ significantly (p > 0.05) from that of Ebonyi river. However, the pH of pond water was significantly low (p<0.05). There was no significant difference in the DO concentration of all study area during the rainy season. Based on the research findings, the following policy recommendations are therefore proffered. World health /bank should please assist the state Government in making available good quality refined urban tap water to the villages and subborbs so as to save the lives of both Urban and Rural dwellers. Safe disposal of domestic wastes and control of industrial effluents should be practical and where possible recycled to avoid these metals and other contaminants from going into the environment. There should be periodic monitoring of the heavy metals concentration in both the fishes and river system to ensure continuous safety of people in the area.