Estudo florístico do componente arbóreo de um fragmento de floresta estacional na região das Missões, Rio Grande do Sul

Abstract

The objective of this work was to evaluate the floristic composition of the arboreal component in a Deciduous Seasonal Forest fragment located in Cerro Largo (28º08’41” S e 54°43’08” O), Rio Grande do Sul state. Data collection was performed using the contiguous plots method, with dimensions of 10 x 10 m (100 m2). Fifty sample units (0.5 hectares) were demarcated, in which were sampled all trees with perimeter (PAP) of the stem at 1.3 m of soil height ≥ 15 cm. It was sampled 748 arboreal individuals representative of 62 species and 53 genders belonging to 28 botanical families. The richest family was Fabaceae (n= 9). The gender with the greatest species richness were Trichilia and Cordia (n= 3), followed by Chrysophyllum, Eugenia, Ilex, Sebastiania and Solanum (n= 2). The species with the bigger number of individuals were Sorocea bon-plandii (Baill.) W.C.Burger, Lanj. & de Boer (n= 141; 18.9%), Actinostemon concolor (Spreng.) Müll.Arg. (n= 86, 11.5%), Inga marginata Willd. (n= 81, 10.8%), Cabralea canjerana (Vell.) Mart. (n= 60, 8.0%), totaling 49.2% (n= 368) of the total of registered individuals. The results obtained in the course of this study suggest that the fragment studied is similar to the other deciduous seasonal forests of Rio Grande do Sul, howev-er, it differs in specific richness and, consequently, in diversity.