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Mining activities cause severe impacts to soil, the restoration of which requires specific management, and proper evaluation and monitoring. In this research, our objectives were to study recovery strategies and integrate indicators for monitoring the reclamation of an agricultural soil after bauxite mining. Distinct fertilizations (nonfertilized control [CT], poultry litter [PL], chemical fertilization [CF], and PL + CF combined) and intercrops (bare soil with no intercrops [NI], grass [G], legume [L], and G + L combined) treatments were used as recovery strategies to restore soil capacity to sustain a coffee plantation. We selected 27 quality indicators to compare the premining condition, postmining (reconfigured topsoil), and 19 months after the application of fertilization/intercrops treatments. We used univariate statistics to select soil quality indicators and multivariate analyses to group the selected indicators into organic, chemical, physical, and microbiological properties. From each group, one representative attribute was selected, and its averaged weight was summarized into a soil quality index (SQI). In postmining, the estimated SQI was approximately 65% lower than in premining. The SQI recalculated 19 months after the application of fertilization (PL or PL + CF) and intercrops (G, L, or G + L) was 23% higher than in postmining and showed strong correlation with coffee bean yield (at 27 months). Coffee bean yield was highest in plots with L or G + L receiving PL or PL + CF. We conclude that organic amendments and intercrops are suitable approaches to recover soil following bauxite mining, and soil indicators can be integrated to properly monitor the land reclamation progress.

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Abstract. The teaching-learning process is influenced by several issues IntroduçãoAprender é uma atividade fundamental e desafiadora para os seres humanos. O contexto institucional exige dedicação dos professores e dos alunos, mas proporciona muita satisfação, principalmente quando os alunos se apropriam do conhecimento e os aplicam em contextos diferentes dos abordados durante o processo de aprendizagem, envolvendose diretamente com as informações recebidas [Svinick e Mckeachie 2012].Alguns alunos têm maior dificuldade do que outros durante a aprendizagem [Freire 1996, Zabala 1998], então a persistência de todos os envolvidos na criação de situações que apoiem o domínio de uma prática ou a compreensão de um assunto são fatores primordiais para que os objetivos sejam alcançados [Wells 1999]. Esta visão está apoiada no conceito de zona de desenvolvimento próximo de Vygotisky, exemplificado na frase: "a distância entre o nível de desenvolvimento atual determinado pela resolução III Congresso Brasileiro de Informática na Educação (CBIE 2014) XXV Simpósio Brasileiro de Informática na Educação (SBIE 2014) _______________________________________________________________________ 476

The reclamation of bauxite‐mined areas can be favored by the application of organic and/or chemical fertilization to restore the vegetation. Otherwise, the impact of fertilizations on soil microbiota or plant–microbe interactions as land reclamation progresses is less understood. To address this issue, we evaluated the impact of organic and chemical fertilization on plants and soil microbial community within the first 36 months of land reclamation in a bauxite‐mined site. The experiment was set up according to a split‐plot design in which the main plots received fertilizations [non‐fertilized control (NF), chemical fertilization (CF; NPK and rock phosphate), organic fertilization (OF; poultry litter), and CF+OF combined], and the subplots received cover crops [no cover crops (NC), grass (B; Brachiaria), legume (S, Stylosanthes), and B+S combined]. Cover crops biomass yield was assessed annually with five field campaigns per year. We used phospholipid fatty acids (PLFAs) to infer the impacts of mining and restoration practices on actinobacteria, Gram‐negative and Gram‐positive bacteria, arbuscular mycorrhizal fungi, and fungi. Accordingly, PLFAs were determined before bauxite mining (pre‐mining), six months after topsoil reconfiguration (post‐mining), and after 14 and 36 months following the application of the fertilizations and cover crops. PLFAs results indicated that in post‐mining, the living microbiota was significantly lower than in pre‐mining. Cover crops biomass yield was highest for B and B+S fertilized with CF+OF at 14 and 36 months. Both parametric and non‐parametric statistics showed a temporal variation in the response of living microbes to the treatments applied. After 14 months, living microbes showed greatest response to OF, while at 36 months their response was strongest in the treatments with highest plant biomass production (B and B+S). These results suggest that in the early stages of land reclamation, living microbial biomass benefit the most from organic fertilizers. As this initial boost decline, living microbes are more likely to thrive in areas undergoing reclamation where they can develop synergistic interactions with plants.

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The expansion of short rotation eucalypt plantations in low soil organic matter (SOM) sandy soils may offer an alternative to improve soil C sequestration. The goal of this study was to estimate the changes in C stocks and emissions in different SOM fractions following conversion of the native Cerrado to pasture and then to eucalypt plantation. Therefore, we studied soils under native Cerrado, planted pasture (cultivated for 34years following the clearing of the Cerrado) and eucalypt plantation (4years). The C and N stocks in particulate organic matter and mineral‐associated organic matter (MAOM) were determined 4years after eucalypt planting. Soil CO2‐C, CH4‐C fluxes and CO2‐C concentrations in soil profile were measured in different seasons over 4years. Variation in the natural abundance of 13C was used to partition the SOM‐C. The soil CO2‐C and CH4‐C fluxes were influenced by soil surface moisture (r= 0.185o and r= 0.430**, respectively), whereas only the soil CH4‐C fluxes correlated with soil surface temperature (r= 0.355**). The highest soil CO2‐C flux in soil under eucalypt occurred after 4years of eucalypt planting (2.5 kg ha−1h−1, approximately 70%). The pasture soil acted as a CH4‐C source to the atmosphere. The pasture MAOM‐C losses in the 0.0–1.0‐m soil layers were not compensated by the new eucalypt C inputs (MAOM‐C lost ~9.6 Mg ha−1). In summary, the recent worldwide expansion of short rotation eucalypt plantations should be carefully considered, particularly under pasture degraded soil sandy soils, because land uses able to increase SOM are priorities.

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