The Cerrado biome has the richest flora among the world's savannas and presents a
high level of endemism. In relation to the state context, the Tocantins is situated in the
geographical transition zone between the Cerrado and the Amazon. The development
of this work aimed to evaluate the floristic and phytosociological composition, as well
as quantify the necromass and lianas in a Cerrado fragment sensu stricto. In an area
of 3.6 hectares, by census, arboreal individuals with chest circumference (CAP)
greater than or equal to 15 cm were identified, which had their height measured, as
well as individuals who presented lianas using as support. In the area, we also
measured the necromass arranged on the soil that was in the area and with diameter
of at least 2 cm, using the methodology of smalian, cubing. In addition, woody lianas
with diameters ≥ 1 cm at 1.30 m were measured. A total of 8,943 individuals belonging
to 75 species were sampled, 69 genera and 33 families of which the families
Vochysiaceae and Fabaceae predominated. The total density of the area and basal
area were, respectively, 2,484 ind.ha-1 and 13,95 m².ha-1. It was verified by the
indexes of Shannon (H '= 3.39) and Pielou (J = 0.79), in comparison with other studies,
the high species diversity and heterogeneity. A total of 1,547 woody pieces were
measured lying on the ground and suspended above the trees with a total density of
430 pieces.ha-1, most of which were composed of twigs. Regarding the lianas, 2,174
individuals (604 ind.ha-1) were sampled, with a mean biomass of 16.81 Mg.ha-1. In
the study area the species that stood out in relation to the phytosociological parameters
were: Myrcia splendens, Byrsonima stipulacea, Qualea parviflora, Machaerium
brasiliense, Qualea multiflora, Magonia pubescens and Astronium fraxinifolium; high
species richness and distribution heterogeneity; few species with the same genera;
and greater abundance of necromasses and lianas in smaller diameters is related to
the structure of the area since most of the woody species is concentrated in small
plants.
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