Composição florística e estrutura da vegetação em área de caatinga e brejo de altitude na Serra da Guia, Poço Redondo, Sergipe, Brasil

• Autor(a) principal: Machado, Wedna de Jesus
• Data de Publicação: 2011
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFS
• Texto Completo: https://ri.ufs.br/handle/riufs/4481
• topic: Semiárido; Mata serrana; Caatinga; Brejo de altitude; Semiarid; Mata serrana; Caatinga; Brejo de altitude; CNPQ::CIENCIAS BIOLOGICAS::ECOLOGIA

The Caatinga, exclusively brazilian biome, stands out by a great diversity of plant species, many of which are endemic, with adaptations to water deficit. In areas of higher altitude inside the biome, can be find enclaves of Atlantic Forest, known as Brejos de altitude or Matas Serranas , who make up core areas of significant importance to the preservation of biodiversity. This study was conducted as to characterize structurally the vegetation of the Serra da Guia, located in Poço Redondo, Sergipe State, Brazil, by means of floristic and phytosociological survey of two areas, one located at the base (Caatinga) and the other at the top of the mountain ( Brejo de Altitude ) with systematic and monthly collection held on track and in 30 permanent quadrats of 400 m2, during the period from october/2009 to september/2010. In total, were sampled 365 species (82 families), being 216 species (58 families) in the area of Caatinga and 257 species (70 families) in the area of Brejo. In the Caatinga, families with highest species richness were Fabaceae (30) and Euphorbiaceae (15), while in the Brejo were Fabaceae (23) and Asteraceae (15). In the sampling of woody stratum, the total richness was 92 species, but the Brejo area had the highest richness that the Caatinga (71 and 47 species, respectively). The most abundant species in the Brejo was Eugenia cf. edulis (n = 655, 18,39%) and in the Caatinga was Pityrocarpa moniliformis (n = 159, 13,86%). The species that presented the highest VI in the Caatinga and in the Brejo were Syagrus coronate and Guapira sp., respectively. The comparison between the dominant species occurring in the Serra da Guia showed that only two (Guapira noxia and Syagrus coronata) of 31 species highlighted are common to the sampled areas, but with significantly different abundances. The values of the index of Shannon-Weaver (H ') and Pielou (J') obtained for the area of Brejo (H = 3,13 nats.ind-1, J '= 0,97) were higher than the area of Caatinga (3,02 nats.ind-1, J '= 0,78). Statistical tests showed significant differences in terms of both diversity index as compared to the richness and floristic composition of the study areas. The value of the Jaccard index (26.9%) indicates that the two areas share less than half of plant species. The Serra da Guia sets in the first Brejo de Altitude described and studied in the State of Sergipe, e the analysis of similarity between plant communities Caatinga and Brejo showed that, although occurring near, these formations have characteristics floristic, physiognomic and structural distinct.