DEGEO - Departamento de Geologia
URI permanente desta comunidadehttp://www.hml.repositorio.ufop.br/handle/123456789/8
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Resultados da Pesquisa
Item Assessing the impacts of mining activities on zooplankton functional diversity.(2016) Moreira, Francisco Wagner Araujo; Leite, Mariangela Garcia Praça; Fujaco, Maria Augusta Gonçalves; Mendonça, Fellipe Pinheiro Chagas; Campos, Larissa Paraguassú; Sant'Anna, Eneida Maria EskinaziMining activities generate countless environmental impacts, including heavy-metal contamination, sorting and increased turbidity. In aquatic ecosystems these impacts can drastically affect the initial links of the food chain, such as zooplankton. Methods: To evaluate how the different mining activities can influence the structure and functional diversity of zooplankton, we investigated the geochemical characteristics of the water and sediment in two small impoundments impacted by different mining activities (kaolin and iron extraction). We also explored zooplankton composition, species diversity and functional diversity (feeding guilds taxa). Results: As expected, the water and the sediment of both of the reservoirs showed high concentrations of trace elements, particularly Al, Ba, Fe, Mg, Mn, Sr and Zn. Zooplankton biomass and diversity were markedly reduced (< 12 μg.DW.L-1 and H’ < 1.5, respectively), and negatively correlated with turbidity and total suspended solids. Small microphages dominated the trophic composition of zooplankton, and an alternation of trophic guilds was not observed, since the dynamics of raptorial organisms was essentially linked to the temporal fluctuation of a single species of rotifer (Polyarthra cf. dolichoptera). Conclusions: In addition to changes in the aquatic habitat and zooplankton composition, the functional niches were also affected by the mining impacts. The use of the functional diversity analysis can emerge as a valuable approach to understand how zooplankton communities respond to drastic environmental changes.Item A Life Cycle Assessment study of iron ore mining.(2015) Ferreira, Hélio; Leite, Mariangela Garcia PraçaThis paper assessed the cradle-to-gate life cycle of an iron ore mining. The study was based on production data from an open pit mine located in the Iron Quadrangle/Brazil. The functional unit was defined as “one tonne of iron ore concentrate produced” and the data used were collected directly from the company's production reports covering the time of one year. The evaluation included the classification and characterization of life cycle impacts, not including normalization and weighting as well as sensitivity analysis of results. The evaluation of impacts used SimaPro-7, Ecoinvent 2.0, Eco indicator'99 and IPCC 2007. The results indicated that the use of grinding media in the processes is the main source of environmental impacts in the iron ore production chain, highlighting its contribution to life cycle impacts on human health and quality of ecosystems. Ore transportation by conveyor belts powered by electricity was more efficient in relation to the generation of impacts on the abiotic resources depletion and on climate changes than ore transportation by diesel trucks because the electricity generation matrix in Brazil has significant participation from hydroelectric plants.