Diatom flora of Lake Iro (Southern Chad): Preliminary observations

Diatoms are microscopic yellow-brown algae widely distributed in aquatic environments, where they play a key role in trophic networks and primary productivity. This study aims to better characterize the current diatom assemblages of Lake Iro, located in southern Chad, a region previously unexplored from a limnological perspective. A taxonomic inventory was conducted based on seven samples collected from different substrates (sediments, plankton, macrophytes), complemented by in situ measurements of hydrochemical parameters (temperature, pH, conductivity, and dissolved oxygen).The results reveal low species diversity, dominated by Aulacoseira granulata, a typical freshwater species that thrives in alkaline, well-mixed waters. The highest diversity indices were observed in samples collected from macrophytes. As the first study of Lake Iro, this work highlights the need for additional, especially seasonal, investigations to better understand the ecological dynamics of this Sahelian lake system.