| Congresso Brasileiro de Microbiologia 2023 | Resumo: 877-1 | ||||
Resumo:The Fundão tailings dam failure, which released approximately 55 million m3 of mine tailings, is considered the largest environmental disaster in the history of Brazil and the global mining industry. This event affected rivers and lagoons in the Doce river basin, as well as at nearby coastal areas, including Abrolhos Archipelago, the largest coral reef complex in the South Atlantic Ocean. However, the biological consequences of this disaster on the environment and corals remain poorly understood. The present study sought to assess the microbiome of sediments, water, and two coral species (Millepora alcicornis and Mussismilia harttii) in the affected areas using 16S rRNA gene amplicon sequencing. Additionally, the study investigated the metal concentration and biochemical markers of metal stress in corals. Over a period of four years (Sept./2018-Mar./2022), with two collections per year and a total of 2468 samples analyzed, a comprehensive understanding of the impact on the microbiome following the dam failure and the existence of an intriguing microbial connection has been established. A substantial abundance of bacterial and archaeal groups associated with heavy metals and mine tailings sediments were identified in almost all samples analyzed, including the corals from Abrolhos. Surprisingly, despite being located 1103 km away from the Fundão dam and 250 km from the Doce river mouth, the microbiome in Abrolhos corals exhibited a higher similarity to the Doce river sediment microbiome than to the Abrolhos sediment and water microbiome. During the rainy seasons, bacterial taxa associated with heavy metals and dam sediment, which experienced a significant increase in abundance in the Doce River, also displayed a very high increase in abundance in the Abrolhos corals, in some cases dominating the coral microbiome. Additionally, the corals microbiome showed an elevated proportion of microorganisms’ indicators of environmental stress and possible dysbiosis. These results suggest that the microbiome of rivers, lagoons, nearby coastal areas, and Abrolhos corals are impacted by the sediment plume of the Doce River, which was generated by the Fundão dam failure. Furthermore, they indicate the presence of a persistent “microbial bridge” connecting the disaster and the microbiome of Abrolhos corals, even years after the event. Palavras-chave: Bacteria, Archaea, Microbiome, 16S rRNA, Millepora alcicornis and Mussismilia har Agência de fomento:Fundação Renova e FEST | |||||