ABSTRACT
The macroinvertebrate community of the bankroot biotope of Eruvbi Stream was studied from October 2021 to March 2022 at three sampling stations along the stream. The physicochemical parameters determined include air and water temperature, water depth, flow rate, electrical conductivity, turbidity, total dissolved solids, total suspended solids, pH, dissolved oxygen, biochemical oxygen demand, hardness, chloride, nitrate, sulphate, calcium, sodium, magnesium, and phosphate. The result revealed that water depth, flow rate, electrical conductivity, turbidity, total dissolved solids, total suspended solids and sodium were significantly (P<0.05) different while air temperature, water temperature, pH, dissolved oxygen, BOD5, hardness, chloride, nitrate, calcium, magnesium and phosphate were not significantly (P>0.05) different. A total of eight hundred and fifty-three (853) macrobenthic invertebrate individuals, which were made up of twenty-two (22) species belonging to two (2) phylum and three (3) classes were observed in the Eruvbi Stream. The macrobenthic invertebrate’s taxanomic group is comprised of 1 species of Oligochaeta, Hirudinea, Ephemeroptera and Zygoptera. 2 species of Arachnida 3 species of Anisoptera and Coleoptera, 5 species of Diptera and 6 species of Hemiptera. The most dominant taxon encountered was Diptera (61.08%), while Hemiptera (5.74%) and Arachnida (6.92%) were the sub-dominant groups. The rare groups were Oligochaeta (0.59%), Hirudinea (0.23%), Ephemeroptera (2.11%), Zygoptera (2.46%) and Coleoptera (4.81%). The diversity indices revealed that taxon richness was highest in station 1 and lowest in station 3. The faunal similarities among the three stations were high.
