Floristics and horizontal structure of the tree vegetation of a ravine in a florest fragment in the municipality of Viçosa, MG

This study was developed in a section of a Montane Seasonal Semideciduous Forest fragment, in the Bom Sucesso Farm, Viçosa - MG - Brazil. This study aimed at finding out about the floristic composition and the phytosociologic structure of the tree component. Ten transects of 50x10m, subdivided into 5 plots of 10x10m each, totalling 50 plots within 5000m² were established. In the sampling, all the tree individuals with a minimum of 15cm of stem circunference at 130cm above ground were evaluated. A total of 151 species pertaining to 108 genera of 45 botanic families were identified. Within 0.5 ha, 820 alive trees and 32 dead standing up trees were sampled, which means a total density of 1704 individuals/ha. The basal area/ hectare was 38.450m² and the average height was 8.43m. The species Euterpe edulis was prominent in the structure of the studied vegetation, with 314 individuals sampled, resulting in a relative density of 37.38%, absolute frequency of 90%, relative frequency (FR) of 8.91%, relative dominance of 18.79%. The Shannon diversity index was 3.52 and the equability was 0.696. The result of floristic composition and phytosociologic structure showed high richness and medium diversity, although most of the species were represented by few individuals.

Floristic composition; phytosociologic structure and Seasonal Semidecidous Forest