Do variations in the composition and structure of vegetation allow floristic groups to be detected in a subtropical moist forest in southern Brazil?

Abstract

Variations in vegetation based on topographic location have become an interest of researchers. However, few studies have verified floristic associations related to the topographic position of a slope. In this work, we analyzed if variations in vegetation allow floristic groups to be detected in a subtropical moist forest. The vegetation was sampled in 25 plots of 400 m² distributed systematically, where individuals with a DBH ? 5.0 cm were measured. We sampled 1,727 individuals and 144 species. The NMDS ordination segregated three groups based on the topographic position of the slope (Monte Carlo, P ? 0.05; ANOSIM, P < 0.001). Euterpe edulis and Sloanea guianensis were notable in the lower and middle sections of the slope, whereas Ocotea aciphylla and Alchornea triplinervia were notable in the upper section. Some species were indicators of the analyzed sectors, such as Actinostemon concolor and Alsophila setosa in the lower section, Cyathea corcovadensis and Rudgea recurva in the middle section, and Myrcia pulchra and Podocarpus sellowii in the upper section. Our results indicate that the floristic and structural variations observed by Veloso and Klein (1959) and Klein (1980; 1984) for Vale do Itajaí in Santa Catarina are statistically valid today, because we verified the formation of different groups according to the topographic position of the slope.