Spatial distribution and structure of benthic macroinvertebrates in an artificial reservoir: Taabo Lake (Côte d’Ivoire)

Abstract

Taabo Lake is facing eutrophication process characterized by a permanent and continuous colonization of its water body by invasive aquatic macrophytes since 1990. Until now, there is limited knowledge of its ecological state. The purpose of this study is to examine the spatial distribution and structure of benthic macroinvertebrates in Taabo Lake. Benthic macroinvertebrates were sampled from July 2006 to June 2007 using an Ekman grab. Four sampling stations were selected on the area of the reservoir along a longitudinal gradient: Sahoua and Ahondo in the upper part; Taabo Cité and Taabo Village in the lower part. Overall, 29 taxa belonging to 17 families, 7 orders and 3 classes were recorded. A total of 4028 individuals were collected. Insecta (53.21%) were most represented, followed by Gasteropoda (36.15%) and Oligochaeta (10.64%). A better knowledge of the ecological traits of species and the identification of indicator taxa will permit to develop a Benthic Quality Index able to monitor the lakes and man-made reservoirs of Côte d’Ivoire.

Keywords: Benthic macroinvertebrates, diversity, structure, lake, Côte d’Ivoire.