Composição florística e fitossociologia de duas áreas de caatinga no Parque Nacional do Catimbau, Buíque, Pernambuco, Brasil

Abstract

Despite the existence of floristic-phytosociological studies of savanna vegetation, very little is known about the vegetation types in this biome as a whole. In this sense there is a consensus among various authors about the need to recognize the heterogeneity and floristic his face. Climate and soil, or together, these two factors are considered key in determining this floristic heterogeneity. The aim of this work was to floristic and phytosociological study in two fragments of woody savanna (Trilha do Cânion¹ and Casa do Artesão²), located in the municipality of Buíque - PE, in sedimentary areas (Quartzipsamments Neosol). Through the method of the quadrants, we studied 10 transects parallel and equidistant 30m transects were demarcated in 10 points every 10m, being sampled individuals (trees, saplings, shrubs and succulents), closer to the center of each quadrant, dead or alive (standing still) with the girth ≥ 9 cm from ground level. For each zone were sampled quadrants 100, 400 points, resulting in 400 individuals. In one area, we sampled 16 families, 24 genera and 26 species, as in area 2, the inventory indicated nine families, 20 genera and 27 species. The families with the largest number of species in area 1 were Fabaceae, Cactaceae and Myrtaceae, in area 2 were: Fabaceae, Euphorbiaceae and Verbenaceae. Already the most abundant taxa were Byrsonima gardneriana and Chamaecrista brachystachya (1), followed by Pityrocarpa moniliformis and Amburana cearensis (2). In area 1, and Fabaceae families Cactaceae showed the highest values of sampled individuals, 18,52 and 14.81% spp. In area 2 highlights were Fabaceae (28.57%), Euphorbiaceae (28.57%) and Verbenaceae (10.71%), households with higher (spp%) include those typically found in sedimentary environments. The vegetation structure was evaluated by the usual parameters by making use of the software FITOPAC (Shepherd, 1995), we determined the number of individuals (NInd), relative density (RelDe), relative frequency (RelFr), relative dominance (RelDo), IVI and IVC for Family / species in the two areas surveyed, among other parameters phytosociological. The analysis results showed that the two areas differ both in physiognomy and in vegetation structure and low species richness.