Restoration success: secondary forests at the margin of the hydroelectric reservoir (Minas Gerais State, Brazil)

Abstract

Disturbance with removal of the original vegetation and intense erosion during construction of hydroeletric reservoir can destroy the vegetation and the natural environmental. , the present study aimed to characterize the correlations between the inventoried tree communities and soil attributes in order to demonstrate the influence of physical and chemical characteristics of the soil on the tree (DE = Degraded; DI = Disturbed and CON = Preserved). A survey was performed with the allocation of 36 plots of 20 x 20 m, in which trees with DBH ≥ 5 cm were sampled. For the soil analysis, two samples were collected within each plot in order to form a composite sample. Correlations between biotic and edaphic arrays had their significance tested using the Monte Carlo permutation test. Edaphic and biotic variables were compared by unifactorial variance analysis (ANOVA), connected to a posteriori Tukey Test. The ordering showed the separation of the plots into three groups (DE, DI and CON) according to the proportion of disturbance levels. The areas in restoration process presented edaphic and tree community composition heterogeneity. The soils of all studied categories were characterized by its low nutrient availability and acidity ranging from medium (DE) to high (DI and PRE) and varying content of organic matter, which is more highly stored in the forest area. The fertility degree and other soil characteristics partially explain the floristic compositions and changes in the abundance of populations in the tree communities.