Potencial da regeneração natural como método de restauração do entorno de nascente perturbada

Abstract

This work evaluated the potential of natural regeneration in the restoration a disturbed water spring surrouding, after stopping the impacts, on forest and wasted grazing land. It was analyzed the structure of the stratum and natural regeneration under canopy and in open area surrounding a water spring under process of recovery, located in Nazareno, Minas Gerais. The tree stratum was assessed in 4 permanent plots (10 × 50 m), sampling, identifying and measuring height of trees with DBH 5 cm diameter. For assessing the natural regeneration, 16 plots (10 × 2 m) were set. Trees with height> 10 cm and DBH <5 cm were identified and measured. The samples were established at 7 and 51 months after the isolation of the area. Phytosociological parameters of the tree and regenerative strata were calculated for each species, classifying them by the type of dispersal and ecological group. Shannon diversity index and evenness were calculated for each community which were also compared by Sorensen index. The results showed that the areas are dissimilar, with most species found at the regeneration under canopy, showing a intake in the system. The communities had a high proportion of zoochoric species and pattern of higher light demanding climax species and a decrease in the proportion of pioneer species from one inventory to another, indicating progress in natural succession. The density of the individuals regenerating under canopy was much greater, probably due to the dominance of Brachiaria in the open area, showing that use of the regeneration as a unique method of recovery should not be applied.