Assessment of Macroinvertebrate Communities and Physico-Chemical Characteristics of a Tropical Stream in Relation to Anthropogenic Activities

The study of water resources is a worldwide goal that requires regular monitoring so as to ensure the maintenance of good water quality especially waterbodies subjected to human activities. To access the impact of anthropogenic activities on waterbodies, many authors study the macroinvertebrate assemblage as well as the physico-chemical properties of water. This study used the approach to investigate the communities’ structure of macroinvertebrates and pollution status of the Ewure stream. Macroinvertebrates were collected from upstream and downstream using appropriate systematic sampling techniques using 500nm D-frame net. The macroinvertebrates were examined under a dissecting microscope and were identified using appropriate identification keys. Water quality parameters were assessed using standard and appropriate measures. A total of 350 individuals were recorded in upstream and 159 individual were recorded in downstream belonging mostly to moderately sensitive species. The stream was dominated by family of Notonectidae, Libellulidae, Gerridae, Belostomatidae and Naucordidae. Species pollution tolerances index recorded categorized the macroinvertebrates as ‘moderately tolerance species’. The result showed that the stream is ecological impaired but with limited impact as shown in the results obtained, due to the less agrochemical farming practices that was observed in the area. Thus, more awareness should be encouraged on the importance of less agrochemical farming so as to maintain and also improve water quality.