Regenera??o natural do estrato arbustivo-arbóreo em área de Caatinga na Esta??o Ecológica do Seridó – RN, Brasil

摘要

http://dx.doi.org/10.5007/2175-7925.2016v29n2p17 The objective of this study was to evaluate the composition and floristic similarity, regeneration origin and the influence of silviculture systems on the diversity and absolute density of regeneration of the shrub-tree stratum in two areas of Caatinga. The first area is in the Seridó Ecological Station and the second is on Pedro Candido Farm, in the city of Serra Negra do Norte, in the Seridó region of RN, Brazil. In each area, 16 subplots of 25m 2 were delimited and individuals with a base circumference ≤ 6 cm and a height & 0.5 m were included in the study. The plants were classified according to origin of regeneration (seeds or budding). The following parameters were calculated: frequency, density, Shannon’s diversity index, Pielou’s evenness index and Jaccard’s index. The sample included 2112 individuals belonging to 13 species, 11 genera and seven families. Considering the two areas, the values for density, Shannon’s index and Pielou’s index diverged in both years of the study. Regeneration by seeds was predominant in the two locations. After 22 to 24 years of silvicultural intervention, it was found that the treatments had no influence on density and floristic diversity.