Harnessing Aquatic Physicochemical Parameters Influencing Macroinvertebrate Fauna In Anambra River Basin For Sustainable Fish Productivity

Abstract

The management-oriented background for harnessing aquatic physicochemical parameters influencing macro invertebrate fauna of Anambra River basin for sustainable fish productivity was studied. The intra seasonal variability in the water quality of the river revealed mean transparency of 1.79 cm, Conductivity of 28.81 μscm^-1, nitrate-nitrogen of 3.23 mgl^-1, total hardness of 6.43 mgcaco3L^-1, biological Oxygen Demand (BOD) of 3.62 mgl^-1, No3-N/Po4-P 0.54 ratio and Co²/DO o0.81 were significantly higher in the dry season than all other parameters which were signicantly higher in he wet season. A toal of 1808 individuals (mosty adults) belongng to 97 species of macro-invertebrate fauna were collected. The overall composition of the fauna in the river basin was dominated by coleopterans and the hemipterans. The estimated annual fish yield of the river basin was 72.91 kg/ha based on a morphoedaphic index. The water quality of the River can be harnessed by controlling and/or prohibiting the discharge of municipal effluents and domestic garbage into the river as well as the continuous use of the riparian zone for agronomy. The maintenance of periphera 50/60 m of thick riparian vegetation can act as buffer strp to check bank erosion is suggested.

Keywords: Macro invertebrates, Physicochemical Parameters, Harnessing, Fish yield

Animal Research International Vol. 4 (2) 2007 pp. 705-712