Navegando por Autor "Gomes, Paula Cristine Silva"
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Item Data set on the bioprecipitation of sulfate and trivalent arsenic by acidophilic non-traditional sulfur reducing bacteria.(2018) Matos, Letícia Paiva de; Costa, Patrícia Freitas; Moreira, Mariana; Gomes, Paula Cristine Silva; Silva, Silvana de Queiroz; Gurgel, Leandro Vinícius Alves; Teixeira, Mônica CristinaData presented here are related to the original paper “Simultaneous removal of sulfate and arsenic using immobilized non-traditional sulfate reducing bacteria (SRB) mixed culture and alternative low-cost carbon sources ”published by same authors (Matos et al., 2018) [1]. The data set here presented aims to facilitate this paper comprehension by giving readers some additional information. Data set includes a brief description of experimental conditions and the results obtained during both batch and semi-continuous reactors experiments. Data confirmed arsenic and sulfate were simultaneously removed under acidic pH by using a biological treatment based on the activity of a non-traditional sulfur reducing bacteria consortium. This microbial consortium was able to utilize glycerol, powdered chicken feathers as carbon donors, and proved to be resistant to arsenite up to 8.0 mg L−1. Data related to sulfate and arsenic removal efficiencies, residual arsenite and sulfate contents, pH and Eh measurements obtained under different experimental conditions were depicted in graphical format.Item Impacts of exposure to mine tailings on zooplankton hatching from a resting egg bank.(2021) Santos, Gleice de Souza; Silva, Edissa Emi Cortez; Balmant, Florinda Moreira; Gomes, Paula Cristine Silva; Sant'Anna, Eneida Maria EskinaziIn the last five years, two colossal envi- ronmental disasters involving iron-enriched mine tailings have occurred in Brazil, affecting many aquatic ecosystems over the short, medium and long- terms. This study investigated whether these iron- enriched mine tailings affect the main biotic strategy to restore zooplankton populations affected by severe stress, i.e., hatching of dormant stages. A 30 day hatching experiment was conducted, using a resting egg bank from a natural lake, exposed to 3 concen- trations of mine tailings: control (0 g), T25 (25 g) and T50 (50 g). A total of 22, 15 and 16 species hatched in the control, T25 and T50, respectively. Conochilussp., Filinia terminalis, Hexartha mira, Bosmina longirostris and Ceriodaphnia silvestrii hatched only in the control, which suggests that these species are sensitive to any concentration of mine tailings. A gradual decrease in richness and hatchling abundance was recorded, from the control (8.0 ± 1.0 SE species and 1597 ± 73.9 hatchlings) to T25 (4.6 ± 1.2 species and 1279 ± 136.5 hatchlings) and then to T50 (2.3 ± 1.2 species and 603.3 ± 61.9 hatchlings). Our results suggest that exposure of zooplankton resting eggs to iron-enriched mine tailings may negatively impact these egg banks in natural ecosys- tems, with potential impacts on the restoration of zooplankton communities after even short-term exposures.Item Incorporação de poluentes em compartimentos bióticos e abióticos de ecossistemas aquáticos do Quadrilátero Ferrífero (MG, Brasil).(2019) Gomes, Paula Cristine Silva; Sant'Anna, Eneida Maria Eskinazi; Costa, Fernanda Vieira da; Costa, Fernanda Vieira da; Pires, Maria Rita Silvério; Barbosa, Paulina Maria MaiaO Quadrilátero Ferrífero (MG) tem sido intensamente explorado desde o século XVII em decorrência das riquezas minerais da região. A intensa produção mineral tem acarretado alterações geomorfológicas e geoquímicas dos ecossistemas naturais, principalmente em lagoas, que recebem poluentes através de escoamento superficial terrestre ou via atmosférica. O presente estudo objetivou avaliar a influência da atividade minerária sob ecossistemas lacustres rasos, analisando a incorporação de poluentes (metais e semimetais), em compartimentos abióticos e bióticos de lagoas montanas permanentes e temporárias. Esse estudo foi realizado em seis lagoas do QF localizadas em um gradiente de baixa, média e alta influência do histórico da atividade minerária e em distintas proximidades do impacto. Foram realizadas análises da concentração de metais e semimetais em amostras de sedimento, água, seston e zooplâncton. Encontramos elevadas concentrações de Al, Fe, Mn, Mg, Cr, e Pb no sedimento, água, seston e zooplâncton. As lagoas mais próximas à mineração apresentaram as maiores concentrações de poluentes. Os compartimentos bióticos foram os maiores responsáveis pela retenção e acumulação de metais e semimetais. Esses elementos tendem a associar-se ao material particulado em suspensão, acumulando-se no seston, a partir do qual podem ser transferidos para a cadeia trófica aquática até o zooplâncton, através das conexões tróficas. Nossos resultados indicaram também que o hidroperíodo exerceu forte influência na dinâmica de poluentes, com o acúmulo potencializado em lagoas permanentes. Nossos resultados sugerem que poluentes oriundos da atividade minerária podem ser incorporados em compartimentos dos ecossistemas aquáticos mesmo naqueles localizados sob relativa distância das fontes emissoras, que o hidroperíodo é um fator relevante na dinâmica desses elementos, e que os componentes bióticos podem constituir marcadores robustos do histórico de contaminação de lagoas.Item Simultaneous removal of sulfate and arsenic using immobilized nontraditional SRB mixed culture and alternative low-cost carbon sources.(2017) Matos, Letícia Paiva de; Costa, Patrícia Freitas; More, Mariana; Gomes, Paula Cristine Silva; Silva, Silvana de Queiroz; Gurgel, Leandro Vinícius Alves; Teixeira, Mônica CristinaThis study was designed to obtain simultaneous sulfate (SO4 2−) and As(III) ions removal by non-traditional sulfate-reducing bacteria (SRB) growing in the presence of a protein biomass (PCF), a solid residual material produced by the poultry industry. Microbial cells and PCF were immobilized into calcium alginate beads to reduce mass losses. Microbial consortium efficiency was tested under different operational conditions: sodium lactate, glycerol and PCF as carbon sources; increasing As(III) content; acidic pH (5.0). Microbial diversity was evaluated by PCR-DGGE. Pantoea agglomerans, Enterobacter sp., Citrobacter sp., Cupriavidus metallidurans, Ralstonia sp. and Burkholderia cepacia were found. With the aim to obtain SO4 2− and As(III) simultaneous removal, three semi-continuous up-flow reactors were constructed and operated for more than 100 days to prove their feasibility and reliability. Both SO4 2− and As(III) ions were removed with 74.8% and 80% efficiency, respectively. Solid products were characterized by SEM-EDX, confirming PCF and non-traditional SRB roles during arsenic immobilization. Arsenic/sulfur compounds (possibly As/sulfides) were produced by reaction between As(III) and biogenic sulfide. Microbial consortium proved its ability of growing in an acidic environment without losing its sulfate reductive capacity by using glycerol and PCF as alternative carbon sources and tap water as micronutrients source. The non-traditional SRB culture removed both SO4 2− and As(III) ions simultaneously, with no prior step needed to guarantee As(III) oxidation to As(V). Two different mechanisms could be involved: (i) precipitation as arsenic sulfide or, (ii) adsorption onto PCF/cells calcium alginate beads.