EM - Escola de Minas
URI permanente desta comunidadehttp://www.hml.repositorio.ufop.br/handle/123456789/6
Notícias
A Escola de Minas de Ouro Preto foi fundada pelo cientista Claude Henri Gorceix e inaugurada em 12 de outubro de 1876.
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4 resultados
Resultados da Pesquisa
Item Traditional ecological knowledge in a ferruginous ecosystem management : lessons for diversifying land use.(2020) Urriago Ospina, Lina Marcela; Jardim, Clarice Morais; Rivera Fernández, Germán Marino; Kozovits, Alessandra Rodrigues; Leite, Mariangela Garcia Praça; Messias, Maria Cristina Teixeira BragaSoils developed on banded iron formations (BIFs) present severe physical and chemical limitations to the establishment and growth of non-native cultivated plants. In Brazil, these areas are extensively exploited by Fe and Al mining, causing impacts that further hamper the growth of plant species for the purpose of ecological restoration or rehabilitation. However, traditional communities have historically managed this type of environment successfully for subsistence crops. An understanding of the methods used for such purpose will help future studies of land-use diversifcation and rehabilitation in these ferruginous soils. The aim of this study was to investigate the traditional ecological knowledge (TEK) of a community with great cultural richness inhabiting areas on BIFs in Ouro Preto, Brazil. Interviewees were selected by the snowball technique. Ethnoecological methods (interviews, free lists and guided visits) were used to record the types of soil management, cultivated species and socioeconomic profle of specialists. Specialists are mainly women over 45 years old, low schooling, born and living in the area for a long period. Trial and error and vertical transmission represent the main forms of TEK acquisition. There was high diversity of praxis in the ecological soil management, as well as of cultivated species (183). The methods used are efcient for the physical and chemical soil improvement, allowing the establishment of species, increasing agrobiodiversity and diversifying land use. The used techniques can provide technologies for the rehabilitation of mined areas, confrming the importance of ethnoecological studies for this purpose.Item Physical stability of iron ore caves : geomechanical studies of a shallow underground cave in SE Brazil.(2019) Brandi, Iuri Viana; Sebastião, Cristiane Silva; Ferreira, Mauri Lopes; Lima, Hernani Mota de; Gama, Maria Filipa Perez daCaves hosted in iron formations are attracting considerable interest due to their scientific and environmental value. Some of these caves are located in or near iron ore mine sites, which represent an important source of income to Brazil. However, the Brazilian legislation requires speleological studies that currently have an impact upon ore reserves and environmental licensing processes. The aim of this study was to apply conventional geotechnical empirical approaches to a cave located within the grounds of an iron ore mine in the Iron Quadrangle and validate it with numerical modelling, to ensure the method's applicability to natural caves under mining activity influence. These studies comprised the mapping of structural, geotechnical and geomechanical features of rocks hosting and surrounding the cave and to propose geotechnical domains. Field data collection covered the geotechnical parameters necessary to calculate the characteristic Mining Rock Mass Rating (MRMR) for each geotechnical domain, and to evaluate the stability conditions using the stability index or hydraulic radius of the cave. These geotechnical parameters were then used to calculate the physical parameters used in two-dimensional numerical simulations to verify the good stability conditions of the cave, corroborating the adequacy of Laubscher's diagram. The results of this study, although comprising only one cave, suggest that Laubscher's diagram is applicable for assessing the geotechnical behavior of iron ore caves.Item Exploring Al, Mn and Fe phytoextraction in 27 ferruginous rockyoutcrops plant species.(2017) Schettini, Antonella Tonidandel; Leite, Mariangela Garcia Praça; Messias, Maria Cristina Teixeira Braga; Gauthier, Arnaud; Li, Haixiao; Kozovits, Alessandra RodriguesWorldwide, substrates naturally rich in Al, Fe and Mn are the subject of mining, generating degradation oflarge areas and producing wastes with high pollution potential for water resources, soil and atmosphere,causing harm to human health and ecosystems. The present study investigated the total and phytoavail-able concentration of these elements in soils and leaves of 27 native plant species from ferruginous rockyoutcrops, finding values above the toxic limits described in literature and environmental legislation.Foliar levels of metals varied widely among species, demonstrating different phytoextraction or exclu-sion potentials, which were not explained by the total concentration of elements or available soil fractions.Although most species are not considered hyperaccumulators, the results indicate the existence of speciesrelated to sites of greater availability of certain metals or that can modify soil quality through their dif-ferent phytoextraction skills, with potential future uses in decontamination, stabilization, phytominingand ecological restoration projects.Item Growing Eremanthus erythropappus in crushed laterite : a promising alternative to topsoil for bauxite-mine revegetation.(2013) Machado, Naiara Amaral de Miranda; Leite, Mariangela Garcia Praça; Figueiredo, Maurílio Assis; Kozovits, Alessandra RodriguesTopsoil is the preferred substrate for areas requiring rehabilitation after bauxite ining. However, topsoil is sometimes lacking and so there is a need to test the suitability of other, locally available substrates. In an abandoned bauxite mine in Southeastern Brazil, small patches of native vegetation spontaneously established in shallow depressions over weathered laterite, suggesting that granulometric reduction may have facilitated the establishment of plants. To test this hypothesis, blocks of laterite collected in the area were crushed to simulate texture observed in the vegetation patches. Topsoil collected in a preserved ferruginous field near to the extraction area was also used as a substrate in which Eremanthus erythropappus seedlings, a native woody species, were grown. Seedlings were cultivated without fertilizers in these two substrates and also directly over the exposed and uncrushed laterite. The species proved to be very promising for the revegetation, showing a high survival rate in all substrates. Higher annual growth rates and higher final biomass values were observed in topsoil, but the granulometric reduction of laterite doubled plant growth rate in comparison to the exposed laterite. This result was likely due to the increased availability of essential nutrients to plants and to the improvement in physical conditions for root growth and functioning. Moreover, seedling allometry was not altered by the type of substrate, suggesting that the species was highly tolerant to the new substrate conditions, a fundamental characteristic for success of revegetation of bauxite extraction degraded areas