Effects of deposition of mining tailings on the colonization of benthic macroinvertebrates in aquatic ecosystems: an experimental study on mesocosmos

Abstract

Mining, although is one of the most important sectors in the national and international economy, is also one of those responsible for several environmental and social impacts. The environmental disaster that occurred in Mariana (MG), with the rupture of the Fundão dam, accurately demonstrates this situation, since it caused approximately 35 million m3 of wastes to be spilled in the water bodies, reaching 40 cities in the states of Minas Gerais and Espírito Santo. This disaster has had a number of socioeconomic consequences (including destruction of rural and urban areas, including the deaths of 19 people, among other effects) and environmental, with loss of species and ecosystem services in terrestrial and aquatic compartments. In view of the need of more information about the impacts caused and your effects on the aquatic biota, the objective of this research is to simulate the disaster conditions from studies in ecosystem models (mesocosmos), evaluating the contribution of the reject and its effects on the structure of benthic macroinvertebrate community. These organisms were chosen because they are good bioindicators of water quality and for their wide application in recolonization studies, since they occupy the primary phase of an ecological succession in a disturbed environment. In this way, complementing with physical and chemical data (such as pH, dissolved oxygen, conductivity, temperature, nutrients, hardness, turbidity, suspended solids and chlorophyll concentration), the objective of this work is to understand the changes caused by the deposition of the reject in the biota, evaluating how the re-colonization process will take place, contributing to the studies that aim to better understand the effects of the greatest socio-environmental disaster of the country in recent years. (AU)