Florística e fitossociologia dos estratos arbustivo e arbóreo de um remanescente de cerrad?o em uma Unidade de Conserva??o do Estado de S?o Paulo

摘要

In this work were allocated 25 permanent plots of 10 m × 25 m and measured the vegetation with diameter of at least one cm at the base. In an area of 0.625 ha were sampled 8,454 ind.ha-1, 121 species, 74 genera and 42 families. The species with higher IVI were Ocotea corymbosa (Meissn.) Mez, Pterodon pubescens Benth., and Xylopia aromatica (Lam.) Mart. The high values of PSoR and IVIA reveal that O. corymbosa e P. pubescens are stand in the entire three community strata, although these species are more common on the superior stratum. The Shannon's index show high floristic diversity (H' = 3.47 nat.ind.-1) and the equitability index (J' = 0.40) show dominance of P. pubescens and O. corymbosa in the area. The diameter and height distributions reveal the abundance in the natural regeneration component due the great stock of young plants that compose the inferior stratum of the community. In the 114 species considerate in the phytosociological analysis, 20 could be considerate rare due the few density of individuals per hectare. The floristic survey characterized the phytophisiognomy of the area like a "cerrad?o". The basis of vertical phytosociological parameters permitted give value to the species with PSoR and IVIA, associating the horizontal phytosociological structure with the heterogeneity and irregularity of the stratum of this "cerrad?o" area.