Assessment of Macroinvertebrate Communities in Enda Gabr Stream, in Mekelle, Northern Ethiopia

Abstract

The aim of this study was to investigate the communities of macroinvertebrates and pollution status of the stream. Macroinvertebrate samples were collected from 8 sites by using appropriate systematic sampling techniques using D-frame net. The collected Mud, sand, small gravels and detritus as well as associated invertebrates were washed through 250 µm sieve. Materials retained on the sieve were sorted and examined under a dissecting microscope and all organisms were removed and placed in labeled vials. Water quality parameters were assessed using benthic macroinvertebrates index and pollution tolerance indexes. A total of 20 taxa belonging mostly to Oligochaeta, Ephemeroptera, Chironomidae, and Diptera were recorded. Macroinvertebrate diversity indicates an overall water degradation and vegetation disturbance effect throughout the stream. Based on the Benthic Macroinvertebrate Index and Pollution Tolerance Index, the water quality of Enda Gabr stream showed possibly impaired and impaired, respectively. The results revealed that human interference in stream water resulted in serious ecological imbalances in the natural life cycle and impact on human welfare. It is recommended that immediate management actions are crucially needed to improve the ecological potential of the stream.

Keywords: Macroinvertebrate, communities, pollution, stream, Enda Gabr