Stream Quality and Benthic Macroinvertebrate Diversity in the Badeye Area, Logone Occidental Province, Southwestern Chad

Abstract

The aim of this study of benthic macroinvertebrates in the southwestern canton of Badeye in Chad was to analyze the community structure in relation to the physicochemical quality of water in the Man baptem tributary. A total of 4,012 benthic macroinvertebrates were identified and counted in 38 families. Arthropods were the most diverse, with 35 families and the most abundant (92.32%) of the total, followed by molluscs (6.65%) and annelids (1.02%). Insects predominated at all sampling stations (89.40%), followed by Gastropoda (6.75%), Malacostracans (2.85%), Hirudinea (0.57%), and Oligochaetes (0.45%). The preponderance of the Chironomidae, Psychodidae, and Physidae families in station A3 implies that the water at this station is of poor quality compared with the other 3 stations. The Shannon–Weaver and Pielou indices are higher at station A3, confirming some of the values of the physicochemical parameters at this station. In general, the four sampling stations are diverse. The abundance of certain benthic groups such as Diptera (Chironomidae) in the Man baptem tributary shows that this watercourse is subject to anthropogenic disturbance.