Macroinvetebrate Assemblages In Relation To Water Quality in River Ngadda, North-Eastern Nigeria

Abstract

To manage river systems effectively, information on their water quality and ecological attributes are essential. The macro invertebrate assemblages in relation to the water quality of River Ngadda, northeastern Nigeria were assessed between May 2013 to January 2014. Two sampling sites, one each at the upstream and downstream part of the river were selected. Water physico‐chemical data for some selected parameters were assessed and correlated with macro invertebrate abundance. All physico-chemical parameters with the exception of Nitrate-Nitrogen were within recommended limits while the macro invertebrate fauna was dominated by the Insecta, Bivalvia and Gastropoda groups with the Nematomorpha the least occurring. There was significant difference in the faunal abundance between the seasons at p < 0.05 with greater abundance in the Harmattan season and least abundance in the dry season. Temperature, depth, pH, DO, conductivity, phosphorus and Iron demonstrated strong influence on the abundance of macro invertebrates in the River and this was further supported by the dominance of the Insecta group which is known to be pollution sensitive. The study showed River Ngadda has a rich fauna and good water quality that are strongly correlated with each other. However, there is a need to periodically monitor the high nitrate–nitrogen levels in the water body and put in remedial action (s) where necessary to forestall eutrophication.