RESUMO A presente pesquisa teve como objetivo avaliar a dinâmica da recuperação ambiental de pilhas de estéril de mineração de calcário por meio da análise da composição e estrutura fitossociológica da regeneração natural. O estudo foi conduzido em um empreendimento minerário localizado em Salto de Pirapora (SP), Brasil, com pilhas de estéril abandonadas desde 1994 e 2013, e um fragmento florestal nativo, totalizando três tratamentos. Em cada área, foram alocadas 12 parcelas de 10 × 10 m, onde todos os indivíduos arbustivo-arbóreos com altura acima de 1,30 m foram amostrados, identificados e avaliados quanto à composição e à estrutura fitossociológica. Foi constatada a ocorrência da regeneração natural nas pilhas de estéril com o aumento de indivíduos e espécies ao longo do tempo. Os resultados indicam que a vegetação presente nessas pilhas está em transição de floresta pioneira para um estágio sucessional mais avançado. Contudo, a Leucaena leucocephala estabeleceu-se mais expressivamente que as demais, inibindo o desenvolvimento de outras espécies. Por fim, sugerem-se ações de manejo para que a sucessão ecológica das pilhas de estéril não seja comprometida.

ABSTRACT The present research had as objective to evaluate the dynamics of the environmental recovery of waste dumps in calcary mining by analyzing the composition and phytosociological structure of natural regeneration. The study was carried out in a waste dumo located in Salto de Pirapora, São Paulo, Brazil, with sterile piles abandoned since 1994 and 2013 and a native forest fragment, totaling three treatments. Twelve plots of 10 × 10 m were allocated to each area, where all shrub-tree individuals with height above 1.30 m were sampled, identified and evaluated for their composition and phytosociological structure. The occurrence of natural regeneration in the sterile cells was observed with the increased number of individuals and species over time. The results indicate that the vegetation present in the waste dumps is in transition from pioneer forest to a more advanced successional stage. However, Leucaena leucocephala has established itself more expressively than other species, inhibiting the development of other species. Finally, management actions are suggested so that the ecological succession of the waste dumps is not compromised.

ABSTRACT This study aimed to evaluate the dynamics of the physical and chemical recovery of the substrates of waste dumps of different ages undergoing natural regeneration, in a calcary mining in Salto de Pirapora - SP, Brazil. Characterization of the vegetation, vegetation and physical and chemical cover of the substrates of the abandoned waste dumps since 1994 and 2013 and the soil of a native forest fragment adjacent to the mining was carried out. Twelve plots of 10x10m were allocated in each environment. It was verified that the soil cover rate with herbaceous, grassy, regenerating and litter of the sterile stacks are similar to the native forest fragment. The same was observed for the physical characterization of soil resistance to penetration, soil moisture content and relative light index. For the chemical characteristics, in all areas sampled there is aluminum deficiency which, consequently, presented low potential acidity and alkaline pH. The CEC of the substrates of the waste dumps presented values similar to the CEC of the native forest fragment, with abundance in some essential nutrients, indicating the possibility of vegetation development in the sterile stacks and the contribution of the natural regeneration to the substrates. Thus, the plant-soil relationship via natural regeneration in the sterile piles contributed to the improvement of the edaphic quality of the substrates over time, being a potential form of recovery in calcary mining. Thereby, the Fabaceae predominated on the waste dumps, especially Leucaena leucocephala, which, despite being an exotic species, is relevant for the current recovery stage of the substrates.