Após o rompimento da barragem de Fundão em Mariana-MG, da mineradora Samarco em novembro de 2015, as atenções se voltaram para a necessidade de um melhor conhecimento e controle das demais barragens de rejeito de mineração. Uma das formas de se investigar eventuais irregularidades dessas estruturas, que se localizam em vales de bacias hidrográficas, é verificar se os volumes declarados pelas mineradoras para as suas bacias de rejeito realmente correspondem às informações prestadas nos respectivos processos de licenciamento ambiental. Em função dos acidentes já ocorridos no Estado de Minas Gerais referentes ao rompimento de barragens de mineração e do potencial de dano ambiental e social resultantes, essa pesquisa teve como objetivo propor uma metodologia para o cálculo independente do volume de rejeitos na barragem Maravilhas II, localizada no município de Itabirito-MG, por meio de análise espaço-temporal, utilizando ferramentas de geoprocessamento e análise geomorfológica. Para isso, foi calculado o volume de rejeito da barragem Maravilhas II através de subtração do MDT de 1977 (antes da construção da barragem) e do MDT atual (2017). O método de cálculo baseado na Grade Regular Retangular, foi considerado mais preciso e, como resultado, obteve-se uma estimativa de 74.366.813 m³ de volume de rejeito inserido na Barragem Maravilhas II. Este resultado mostra que a barragem se encontra em conformidade com a legislação ambiental, que prevê um volume máximo de 76.000.000m³. Concluiu-se que a metodologia pode ser utilizada para estudos semelhantes para o caso de outras barragens, visando maior controle dos volumes de rejeitos das barragens e contribuir para o monitoramento destas, minimizando ou evitando possíveis impactos ambientais, sociais e econômicos causados pela atividade mineradora.

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The study area was surrounding Córrego do Feijão Mine, located in the city of Brumadinho/MG, Brazil. From this proposal, we present the analysis of the effect of disruption of one of the tailings dams of the Córrego do Feijão Mine, which took place in January 2019, under the responsibility of Vale S.A. The rupture culminated in mud flow. A study and characterization of the area was made, to understand the flow of the waters, and consequently, the mud. In addition, it was possible to obtain information on the land use of the area before and after the break using remote sensing (Sentinel-2A) supervised image classification. Through a spatial and temporal analysis, it was estimated that the mud reached a total of 2.48 km 2 , being the class of robust vegetation the most affected by the disaster in numerical terms. The typology of anthropic areas, despite being the smallest area hit by mud, was the one that suffered the greatest impact. The importance of an analysis of the elements that belong in the area of study and how they behave, in order to avoid and mitigate situations of vulnerability is considered very important. Finally, it is emphasized the relevance of a spatial planning studies that considers the integrated planning between the juxtaposition of human activities, social and spatial relations and their various impacts on the landscape.

This article had the main objective to identify Landscape Unities corresponding to the vegetation in the Quadrilátero Ferrífero area, in Minas Gerais. The study looks to contribute with the identification of homogeneous areas in the shape of territorial unities, for the composition of methods about the territorial strategic planning. For this, nuclear area landscape metrics were used, shape index and fractal connectivity, identified as the main metrics which depict quality and vegetation fractal embrittlement condition. Afterward, a Multicriterial Analysis by Evidence Weight according to the priority level for each metric, for integration of the analysis and identification of the greater values fractal bearing in mind the three aspects. As a result, two main unities were obtained: notable vegetation landscape; and vegetation with a higher vulnerability to transformation. Was observed a concentration of notable landscapes of vegetation on the central and southeast Quadrilatero’s areas, mainly at the Serra do Gandarela, Serra da Moeda and Serra do Caraça. In counterpart, the areas corresponding to the south and north of the Quadrilatero, besides being closer to the urban centers, has shown to be more likely to be transformed due to the isolation of the fragments. Stem from this analysis, the importance of the Conservation Units maintenance is bolstered, which are fundamental to the natural resource’s protection. The landscape metrics is rated as an important tool of landscape analysis through pattern identification and the understanding of the dynamics of a geographic region. At last, the multicriteria analysis is understood as an important tool for supporting the decision making, being able to evaluate different variables to obtain interest rankings, in agreement with the demanded objectives.