Impact of abattoir waste on Woji Creek, Port Harcourt, Nigeria, using physicochemistry and macrozoobenthic diversity indices

Abstract

The impact of waste discharge from Zoo abattoir, Port Harcourt, on the environmental quality of Woji Creek was studied from April 2001 to March 2002 using physicochemistry and diversity of benthic animals as indicators. Priority physicochemical parameters (total suspended solid, dissolved oxygen and biochemical oxygen demand) indicated high organic enrichment, chiefly due to inputs of bloody effluent. The burning of animal skin with discarded car tyres to produce kpomo, a common local soup component, contributes to the creek's quality alterations. Ironically, diversity of zoobenthos was highest at the area receiving the abattoir effluents compared to areas upstream and downstream from that point. Possible explanations are provided for the inverted diversity trend using the Hutcheson Index, which indicated significant diversities in invertebrate species amongst the three sample sites. The inefficiency of ecosystem quality evaluations using isolated single indices is also discussed.