AQUATIC MACROINVERTEBRATE STRUCTURE AND DIVERSITY IN ANGUEDEDOU STREAM (ANGUEDEDOUBASIN : COTE DIVOIRE)

Aquatic macroinvertebrates play an important rôle in ecosystems and are usually used as bioindicators to assess their health. This study aim to assess the structure and diversity of these organismson one hand and the effect of the environmental variables on the characteristics of their communities in Anguededou Stream basin (Côte dIvoire) on the other hand. Six stations were monthly sampled during one year period (March 2018 - February 2019). A total of 171 taxa belonging to 77 famillies and 14 orders were recorded. The Insecta class was the most diversified with 150 taxa (87.20% of total species richness) followed by the Gasteropoda, Malacostraca, Acheta and one species in Oligocheta. The highest values of diversity indices were collectedin the upstream station A1 while highest values of Sorensen similarity index were found between the midstream stations (i.e. A3, A4, A5). A strong positive correlation between conductivity, turbidity, salinity, and a negative correlation with dissolved oxygenwas found with the Chironominae subfamily, and the species Diplonychus sp., Hydrobius sp., Hydracharina sp., Hydrochara sp. and Physa marmorata, while the Tanypodiinae subfamily was highly associated with increased of dissolved oxygen. Macroinvertebrates diversity and species composition was found significantly affected by anthropogenic disturbances.