Avaliação estrutural do componente arbóreo-arbustivo em área de preservação permanente degradada em ecossistema ribeirinho intermitente no Cariri Paraibano.

Abstract

This study aimed to evaluate the phytosociological parameters of an adult woody component in a degraded riparian forest in the municipality of Serra Branca, semi-arid region of Paraíba, Brazil. The riparian forest of the “Lagoa da Serra stream” (7°30'04.32'' S and 36°42'13.12'' W; 511 m altitude) was the ecological system selected for this research. Fifty contiguous plots of 10 x 20 m were distributed along the watercourse in the study area. Standing living and dead shrub-tree specimens, with stem diameter at ground level (DNS) ≥ 3 cm and total height ≥ 1 m (inclusion criteria) were sampled. The absolute and relative values of density, frequency, and dominance, as well as vegetation cover and importance values, were calculated. The values of diversity and equability were also determined. The individuals were classified into diameter and height classes. Twenty species, distributed in ten families and sixteen genera, were recorded. Prosopis juliflora (Sw.) DC. had the highest phytosociological parameter values. Regarding the importance value, in decreasing order, P. juliflora, Cereus jamacaru DC., Cynophalla flexuosa (L.) J.Presl, and Jatropha mollissima (Pohl) Baill were the most representative species, as well as the category dead. The sum of the percentages of these species with the category dead represented 76.99% of the total importance value. P. juliflora accounted for 50.71% of the importance value in the analyzed community. The values of diversity and equability were 1.63 nats.ind.-1 and 0.535, respectively. The first three classes of diameter (3–12 cm) and height (1–4 m) represented 69.84 and 72.21% of the total number of sampled specimens, respectively. Therefore, the data presented here are important to guide strategies for the management and recovery of degraded riparian systems in the Caatinga, thus also being a relevant contribution to the management of water resources in the semi-arid region of Brazil. The dissertation aligns with the items 6 and 15 of the 2030 agenda. Item 6 - Potable water and sanitation; Item 15 - Earth life.