RELATIONSHIP BETWEEN SOIL SEED BANK AND CANOPY COVERAGE IN A MINED AREA

• Published in: Revista árvore 2019-01, Vol.43 (4)
• Main Authors: Balestrin, Diego, Martins, Sebastião Venâncio, Fonseca, Wesley, Cosimo, Luiz Henrique Elias
• Format: Article
• Language: English
• Subjects: FORESTRY; Mining; Natural regeneration; Restoration of degraded areas
• ISSN: 0100-6762; 1806-9088; 1806-9088
• DOI: 10.1590/1806-90882019000400003

ABSTRACT The objective of this study was to evaluate and correlate information about soil seed bank and canopy (%Canopy Openness and Leaf area index-LAI) in a mined area in restoration process through natural regeneration. The study area is located in Zona da Mata of Minas Gerais, which presents predominance of Semideciduous Seasonal Forest, and has an area of 0.5 ha in process of natural regeneration after six years of bauxite exploitation (without any intervention). Along the area, ten plots of 45x29cm were allocated and distributed in the best way to represent the whole area in restoration process. Seed bank diversity and canopy characteristics were evaluated in these plots, the last one using a NIKON D40X photographic camera, with fisheye lens of 8mm. As results, 8280 individuals (tree, shrub, herbs, and vines) were found, totaling 51 species and 24 botanical families. The Shannon diversity index (H’) was 2.770, and the equability (J) was 0.705, which demonstrate an average diversity in this area, with a density of 2114.94 germinated seeds m-2. Through the evaluation of the seed bank, the presence of exotic species (23.5%), the dominance of the pioneer species (68.6%), as well as high dispersal by wind (52.9%) were verified in the area. According to canopy characteristics, a significant variation between different points/regions within the study area was found, while patterns of existence of certain herbs as a function of canopy openness (lower vegetal cover/clearings) were also identified, as well as in response to spatial proximity between the allocated plots, confirming the high correlation between these two variables and their importance in the process of forest restoration. RESUMO Os objetivos deste estudo foram avaliar e correlacionar dados do banco de sementes do solo e do dossel (abertura de dossel-% Canopy Openness e índice de área foliar-IAF) em uma área minerada em processo de restauração por regeneração natural. A área de estudo localiza-se na Zona da Mata Mineira, que apresenta predomínio de Florestas Estacionais Semideciduais, e possui área de 0.50 ha em processo de regeneração natural após 6 anos da exploração de bauxita (sem nenhuma intervenção). Foram plotadas 10 parcelas de 45x29cm ao longo da área, distribuídas de forma a representar toda a porção em processo de restauração. Nestas parcelas foram avaliadas a diversidade do banco de sementes e as características de dossel, estas últimas coletadas através de uma câmera fotográfica NIKO