Evaluation by benthic macroinvertebrates of the state of health of some rivers in the south Cameroon region

Benthic macroinvertebrates are the best indicators of the ecological quality of watercourses because of their specific diversity, their sensitivity, their variable life span and their capacity to adapt to all types of environments. In order to determine the health status of some rivers in the Southern Cameroon Region, a study was conducted in Kribi in the Ocean Department between February 2022 and February 2023. Physicochemical analyses were carried out according to conventional methods. Sampling of benthic macroinvertebrates was done using the multihabitat approach. The results of physicochemical parameters revealed that the water courses were well oxygenated, with a slightly acidic pH with little disturbances from anthropic activities. The abundance of benthic macroinvertebrates showed 17055 individuals collected belonging to 2 phyla, 3 classes, 19 orders, 59 families and 113 genera. The class of Crustacea dominated with 7693 individuals or 45.10% of relative abundance, followed by Gastropods with 5174 individuals or 30.33% of relative abundance and Insects with 4188 individuals or 24.55% of relative abundance. The taxonomic diversity, coupled with the EPT, EPTD, EPTC and EPTH indices, revealed that the water from these water courses is of good ecological quality.