Diversity and taxonomic structure of aquatic macroinvertebrates in a fluvio-lacustrine system in south-west Côte d’Ivoire: The case of the Soubré hydroelectric dam lake

The macroinvertebrate inventory was carried out using samples taken at 6 stations distributed along the longitudinal profile of Soubré lake and downstream part Sassandra river. Sampling monthly from July 2019 to February 2020. A total 20581 individuals belonging 117 taxa (genera species), 60 families, 17 orders classes were recorded. macrofauna largely dominated by molluscs, which accounted for 55.69% richness collected. Insects 40.26% abundance organisms Annelids crustaceans poorest groups in population. Coleoptera most abundant order terms numbers individuals, Thiaridae family. Individuals Malacostracan faunal group represented 2.68% population collected aquatic environments fluvio-lacustrine environment. This only sampled river environment, i.e. Tiémé (TIE, upstream dam), Pont (PON) Karmel (KAR, dam) stations. Arachnids (0.61%), bivalves (0.57%) annelids (0.29%) appear be present anecdotally or even absent other sites. In qualitative macroinvertebrates, there 96 Insect class, representing 82.05% diversity environment sampled. However, Gastropods had 12 sampling located fluvial recorded high taxonomic diversity: (73 taxa), (68 taxa) (62 contrast sites lacustrine lowest richness. Shannon indices (H') vary spatially, with averages H'=3.71 TIE site H'=2.85 KPE station. Pollution-sensitive species such as Chironomidae, Viviparidae predominantly abundant. dissimilarity observed between fluvial-lacustrine zone has a greater macroinvertebrates than Taabo lakes. Anthropogenic activities are main factors influencing this ecosystem. study opens up scientific question on different aspects research taxonomy, ecology functional structure invertebrates ecosystem further field.