Analysis of the structure and spatial distribution of Pilosocereus pachycladus subsp. pernambucoensis in vegetation of Caatinga and brejo de altitude

ABSTRACT

Knowing the distribution and spatial pattern of species within a plant community is essential for planning conservation strategies and establishing sustainable management measures in forest formations, especially in Caatinga areas. In this sense, the aim of the study was to analyze the structure and spatial distribution of Pilosocereus pachycladus F. Ritter subsp. pernambucoensis (F. Ritter) in natural populations in areas of Caatinga and Brejo vegetation in the semi-arid region of Paraíba, in the municipalities of Bananeiras and Arara, respectively. In the study areas, 25 plots of 20 m x 20 m were demarcated, totaling a sample area of 10,000 m² (1 ha). Within the plots, all individuals were labeled and the total height and circumference were measured at the base of the stem using a measuring tape. The spatial structure of the populations was obtained by collecting the geographic coordinate of each individual in each area and expressed through maps of spatial distribution. 61 specimens were sampled in the Caatinga of Bananeiras, with an absolute density of 61 ind.ha^-1 and absolute frequency (FA) of 52%. 64 specimens were sampled in the Caatinga of Arara, with an absolute density of 64 ind.ha^-1 and absolute frequency (FA) of 56%. The two populations were arranged in a cluster pattern (Pi = 3.74 and 3.47, respectively). P. pachycladus subsp. pernambucoensis of the two areas have a habit of aggregate growth and population structure with few regenerating individuals. Regional conservation actions for Cactaceae species in their habitat need to take these findings into account to ensure the survival of these species.

Keywords
Cactaceae; Conservation; Population ecology; Facheiro