Diatomeas del registro sedimentario del sistema lagunar Yahuarcaca, Amazonas, Colombia

Studies on diatoms in the Amazon are relatively scarce despite the interest in the great diversity of this region. The taxonomic analysis of Amazonian diatoms improves our understanding of the diversity of aquatic ecosystems and serves as a reference for paleoecological studies. Here, we aimed to characterize the diatom composition of the sedimentary record of the Yahuarcaca lagoon system. This lake is of special interest to local communities, given its different degrees of connection with the Amazon River. We studied two sediment cores in Lago Largo (YAH-1) and Boa Anaconda (YAH-4) and divided them by centimeters to obtain 120 and 121 samples, respectively. We analyzed the diatom composition and counted the diatoms in each core. Our results indicated that both cores had a similar taxonomic composition with 167 diatom morphotypes distributed in three classes, 12 orders, 26 families, and 41 taxonomic genera. The most diverse diatoms were the symmetrical birraphideans, Pinnularia being the richest genus. As for the relative abundance, the most representative species in both cores was Aulacoseira veralucidae Tremarin, Ludwig y Torgan from the centric functional group. Our study expands the inventory and knowledge about diatoms in aquatic environments in the Colombian Amazon region; it also presents an iconography that can be used in future works on the ecology of Amazonian species and paleoenvironmental reconstructions in the area.