THE ZOOBENTHOSE COMMUNITY OF ORHIONMWON AND IKHIOGBE RIVER

ABSTRACT

Zoobenthose communities are very sensitive to environmental conditions and they are very important indicators used for evaluating the ecological status of aquatic ecosystems. This investigation on the zoobenthose invertebrates of Orhionmwon and Ikhiogbe River was carried out from June to November, 2021 from four stations to know the community of these zoobenthose organism. The physiochemical parameters and zoobenthose samples were collected on monthly basis for six months. Zoobenthose were collected using the filter sieve method from the vegetation beside the shoreline of each station. The estimated values for PH, conductivity, dissolved oxygen and biological demand were within the range of most tropical freshwater bodies. A total of 25 taxa from 25 genera comprising 373 individuals were collected from the study area. The dominant groups were Arthropods, and Annelids while Mollusca constituted the least. Among the Arthropods, the family Baetidae was dominant in all stations. Species richness was highest at station 3 and 4 and least at station 2. Eveness values ranged from 0.7 at station 2 to 0.3 at station 3 and 4. Relative abundance was highest at station 3 (135) and least at station 2 (30). This study proved that the Orionmwon and Ikiogbe River is unperturbed and a zoobenthose encountered are characteristics of a tropical freshwater habitat.