DEGEO - Departamento de Geologia
URI permanente desta comunidadehttp://www.hml.repositorio.ufop.br/handle/123456789/8
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Resultados da Pesquisa
Item Metabarcoding of soil fungal communities in rupestrian grassland areas preserved and degraded by mining : implications for restoration.(2023) Figueiredo, Maurílio Assis; Silva, Thamar Holanda da; Pinto, Otavio Henrique Bezerra; Leite, Mariangela Garcia Praça; Oliveira, Fábio Soares de; Messias, Maria Cristina Teixeira Braga; Rosa, Luiz Henrique; Câmara, Eduardo Aguiar Saraiva; Lopes, Fabyano Alvares Cardoso; Kozovits, Alessandra RodriguesRupestrian grasslands are vegetation complexes of the Cerrado biome (Brazilian savanna), exhibiting simultaneously great biodiversity and important open-pit mining areas. There is a strong demand for the conservation of remaining areas and restoration of degraded. This study evaluated, using next-generation sequencing, the diversity and ecological aspects of soil fungal communities in ferruginous rupestrian grassland areas preserved and degraded by bauxite mining in Brazil. In the preserved and degraded area, respectively, 565 and 478 amplicon sequence variants (ASVs) were detected. Basidiomycota and Ascomycota comprised nearly 72% of the DNA, but Ascomycota showed greater abundance than Basidiomycota in the degraded area (64% and 10%, respectively). In the preserved area, taxa of different hierarchical levels (Agaromycetes, Agaricales, Mortierelaceae, and Mortierella) associated with symbiosis and decomposition were predominant. However, taxa that colonize environments under extreme conditions and pathogens (Dothideomycetes, Pleoporales, Pleosporaceae, and Curvularia) prevailed in the degraded area. The degradation reduced the diversity, and modified the composition of taxa and predominant ecological functions in the community. The lack of fungi that facilitate plant establishment and development in the degraded area suggests the importance of seeking the restoration of this community to ensure the success of the ecological restoration of the environment. The topsoil of preserved area can be a source of inocula of several groups of fungi important for the restoration process but which occur in low abundance or are absent in the degraded area.Item Native grass sod and plug production as an alternative technique to restore neotropical rupestrian grassland after mining.(2023) Figueiredo, Maurílio Assis; Messias, Maria Cristina Teixeira Braga; Leite, Mariangela Garcia Praça; Kozovits, Alessandra RodriguesDespite the importance of grasses in the structure and functioning of tropical grasslands, there is still a lack of efficient and economically viable techniques to produce and introduce grasses in restoration projects. Here, we evaluated the sod and plug-plant production and planting of a native grass from Brazilian rupestrian grasslands, Sporobolus metallicolus, in a post-bauxite mining. To produce the sod, we used post-mining substrate and its mixture with commercial substrate. Then, we sowed 270 seeds of S. metallicolus on a 4-cm layer of substrate in 144-cm2 trays. Eighty days after sowing, we subdivided the contents of each tray (substrate + plant) into 4 × 3–cm plug-plants. Plug-plants were planted in the degraded area with and without the incorporation of litter from an adjacent conserved rupestrian grassland. We also evaluated the cost of production of each plug-plant. The mixture of substrates provided greater plant growth and rooting, obtaining plug-plants with an average of 13 individuals, dry mass of 270 mg, and estimated cost of US$ 0.0045. In the degraded area, the addition of litter increased shoot biomass gain. Plant survival was 100% with and without litter addition and the plants started seed dispersal at 7 months after planting. The production of S. metallicolus plugs with the mixed substrate and the growth of plants in the post-mined area showed promising results and reduced costs, indicating technical and financial feasibility. The presented techniques can be an option for introducing grasses in degraded areas and optimize the use of seeds.Item Seed covering and dry periods in the rainy season interfere with direct seeding success in the restoration of post-mined grasslands.(2021) Figueiredo, Maurílio Assis; Messias, Maria Cristina Teixeira Braga; Leite, Mariangela Garcia Praça; Kozovits, Alessandra RodriguesAmong the limitations for the use of direct seeding in the ecological restoration of severely degraded areas in tropical grasslands, the association between dry periods and an inhospitable substrate stands out. This work evaluated whether covering seed with a soil layer and the addition of a thin topsoil layer to the degraded substrate interferes with native plant establishment in degraded areas. The effect of rainfall variations on direct seeding results was also measured. The establishment of seven native species was evaluated under four different conditions: 1) seeding on degraded substrate, 2) seeding covered by 1 cm degraded substrate layer, 3) seeding on 1cm topsoil layer, and 4) seeding covered by 1 cm topsoil layer. In general, species with smaller seeds showed higher establishment percentages in treatments in which seeds were deposited on the substrate. Legume species, which have larger seeds, achieved better establishment percentage when seeds were covered by the substrate. The addition of topsoil was beneficial for Bulbostylis fimbriata (Cyperaceae), while for the other species, the effect was null or harmful. Data also showed that rainfall amount and distribution affected the establishment rate. Direct seeding is an advantageous alternative for the ecological restoration of tropical grassland degraded by mining. Better knowledge on sowing management and behavior of native species can contribute to improving the efficiency of this technique.Item Direct seeding in the restoration of post-mined campo rupestre : germination and establishment of 14 native species.(2021) Figueiredo, Maurílio Assis; Messias, Maria Cristina Teixeira Braga; Leite, Mariangela Garcia Praça; Kozovits, Alessandra RodriguesDirect seeding in the restoration of degraded areas requires less financial investment and facilitates the use of greater diversity of species from different functional groups than traditional planting of seedlings. However, the application of this technique in the ecological restoration of post-mined areas in grassland environments is still poorly investigated. This study evaluated seed germination under controlled conditions, seedling establishment and associated costs of 14 species native to the Brazilian campos rupestres through direct seeding in a post-mined area. The effects of the incorporation of plant material (litter) to the degraded substrate on plant establishment were also measured. Under controlled conditions, 64% (9 out of 14) of the evaluated species showed germinability between 30 and 77%. Under field conditions, one year after, it was observed that the incorporation of plant litter to the substrate allowed the establishment of 49 individuals m− 2 of nine species, four of which with establishment percentage and cost per seedling of, respectively, 1.4–6.2% and US$ 0.006–0.09. In the other treatments, no significant plant establishment was observed. Despite the low percentage of establishment, direct seeding combined with the incorporation of plant litter to the substrate allowed the revegetation of a post-mined area with viable cost. The use of suitable species for direct seeding combined with techniques that promote improvements in substrate conditions is critical to increase establishment success using direct seeding in the ecological restoration of campos rupestres post-mined areas. Further studies on techniques to improve substrate quality and seed germination of native species of campos rupestres are requiredItem Apoplast-symplast compartmentalization and functional traits of iron and aluminum in promeristematic tissues of nematode induced galls on Miconia spp.(2020) Arriola, Igor Abba; Figueiredo, Maurílio Assis; Souza, Daniela Boanares de; França, Marcel Giovanni Costa; Isaias, Rosy Mary dos SantosThe nutritive tissues of galls induced by Ditylenchus gallaeformans (Nematoda) have promeristematic capacity, which may turn these galls into sinks of Al on their Melastomataceae Al-accumulating hosts. Such a sink of Al may affect gall growth and mineral nutrient intake. Based on the fact that galls are good models for plant developmental studies, we aimed to understand how Al-accumulating host plants in the Cerrado environment deal with Al toxicity in subcellular levels. Here, we used the ICP-OES method to check the variations on mineral nutrients, and the morin, hematoxylin, and Prussian blue stainings for Al and Fe histolocalization in galls induced on four Miconia species of the Brazilian Cerrado. We confirmed the new Al-accumulating feature for two Miconia species of the Cerrado environment. Furthermore, we found that Al accumulates in lesser concentrations in gall tissues than in non-galled tissues of the Miconia hosts. Staining methods indicated that the polyphenols avoid Albinding to the apoplast and the nucleolus of the promeristematic cells, and mediated its binding to parenchyma cell walls. As well, we inferred that Fe3þ is transported by xylem and stored in gall parenchyma, where it is reduced to Fe2þ, being available in gall nutritive cells. Our results demonstrated an Al compartmentalization between the apoplast and symplast of the inner cell layers in galls, as well as indicated the phenolics action against Al-toxicity and toward Fe availability for the diet of Ditylenchus gallaeformans.Item Influence of soil texture on nutrients and potentially hazardous elements in Eremanthus erythropappus.(2015) Figueiredo, Maurílio Assis; Leite, Mariangela Garcia Praça; Kozovits, Alessandra RodriguesUnderstanding the factors that control uptake rates and allocation of chemical elements among plant organs is a fundamental prerequisite to improve phytostabilization techniques of hazardous elements in contaminated areas. The present study shows evidence that different substrate textures (coarse and fine laterite) do not significantly change the partitioning of root and shoot dry biomass and with few exceptions, do not significantly affect the final average concentration of elements in Eremanthus erythropappus, but change the root:shoot allocation of both essential nutrients and elements potentially toxic to biota. Growth on coarse laterite resulted in significant higher K (30%), Mg (34%), P (25%), S (32%), Cu (58%), and Na (43%) concentrations in roots and lower Cd concentration (29%). In shoots, coarse laterite led to reduction in K, Fe, Al, and Cr and increase in Na and Sr concentrations. Changes in element allocation could be, in part, a result of differences in the water availability of substrates. Matric potential in coarse laterite was significantly lower in at least 47% of the days analyzed throughout the year. Changes in element phytoextraction or phytostabilization potential could influence the efficiency of rehabilitation projects in areas degraded by mining activities.Item Efeito de diferentes granulometrias de substrato laterítico nas relações geoquímicas, hídricas e no crescimento de Eremanthus erythropappus em uma área degradada pela mineração.(2014) Figueiredo, Maurílio Assis; Kozovits, Alessandra Rodrigues; Leite, Mariangela Garcia Praça; Dias, Luiz Eduardo; Messias, Maria Cristina Teixeira Braga; Kozovits, Alessandra RodriguesEm todo o mundo, a recuperação de áreas degradadas (RAD) tem sido considerada oportunidade ímpar de se devolver ao ambiente parte da diversidade local de plantas e outros organismos e, com isso, promover o restabelecimento dos serviços ambientais característicos dos ecossistemas nativos. Em áreas pós-mineração de ferro e bauxita, entretanto, a implantação de projetos de RAD que contribuam para o restabelecimento dos serviços ambientais é limitada pelo pouco conhecimento sobre a biologia de espécies nativas de fitofisionomias que ocorrem sobre as jazidas minerais e a carência de metodologias que promovam melhorias nos substratos degradados de forma a facilitar o estabelecimento vegetal. Técnicas como a redução granulométrica de substratos degradados podem melhorar diversas características destes, facilitando assim o estabelecimento vegetal. O presente estudo teve como objetivo avaliar o crescimento e a absorção de elementos químicos por Eremanthus erythropappus, espécie pioneira e nativa dos campos ferruginosos, em diferentes substratos: (1) topsoil retirado da área de referência e laterita, retirada da área degradada, triturada em dois conjuntos granulométricos diferentes (2) laterita grossa e (3) laterita fina. Buscou-se também verificar os efeitos da presença das plantas sobre a disponibilidade de elementos químicos nos substratos. Na área experimental, foram dispostos ao acaso os seis tratamentos que consistiam dos três diferentes substratos com e sem o plantio de mudas de E. erythropappus. Os substratos utilizados foram caracterizados quanto a granulometria, fertilidade e concentração dos diferentes elementos químicos. Também foi determinada a concentração de elementos químicos nos órgãos das plantas, o crescimento relativo dessas, e o potencial mátrico dos substratos. A redução granulométrica das lateritas possibilitou o crescimento das plantas, sendo que não houve diferenças entre as plantas das distintas granulometrias, que por sua vez cresceram menos que as plantas do topsoil. Os substratos com e sem E. erythropappus apresentaram comportamento semelhante, observando-se redução da concentração dos elementos químicos após um ano em condições de campo. A granulometria interferiu na disponibilidade de água nos substratos. A laterita grossa apresentou maior infiltração e menor capacidade de retenção da água da chuva. Eremanthus erythropappus demonstrou capacidade de controlar a absorção dos elementos químicos independentemente da concentração destes nos substratos. Em adição, a espécie mostrou-se tolerante a concentrações elevadas de Al e Fe. Tendo em vista a ausência de diferenças significativas no crescimento das plantas entre as distintas granulometrias das lateritas, conclui-se que a utilização da laterita grossa é melhor, pois a preparação desta demanda menor custo financeiro. Além disso, a textura mais grossa pode contribuir para a redução da erosão hídrica e eólica e aumento da recarga do lençol freático. Eremanthus erythropappus apresentou plasticidade às alterações edáficas e tolerância a substratos distróficos com altas concentrações de alguns elementos tóxicos como o Al e o Fe, indicando ser apta para o uso em projetos de revegetação em áreas degradadas pela mineração de Fe e Al.Item Otimização de metodologia de digestão de folhas de espécie dos Campos Rupestres.(2014) Araújo, Letícia Pereira; Silva, Matheus Albuquerque da; Faria, Efigênia Miranda de; Abreu, Adriana Trópia de; Figueiredo, Maurílio Assis; Leite, Mariangela Garcia Praça; Kozovits, Alessandra RodriguesItem 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