Florística do banco de sementes no solo em diferentes estágios de regeneração natural de Caatinga.

The present study aimed to evaluate the floristic composition of the seed bank in the soil and litterfall at different stages of natural regeneration in areas of Caatinga. The study was conducted at Farm Cachoeira of São Porfírio, in the municipality of Várzea, PB, where four were select areas, one with native pasture and three in different stages of natural regeneration. For sampling the seed bank were randomly collected 144 samples, and the methodology used to determine the floristic species composition of the seed bank was of seedling emergence and recognition in herbarium. To assess the floristic diversity were estimated index of diversity Shannon-Weaver (H'), the index Pielou evenness (J'), and similarity of Jaccard (Sj). The floristic composition of the seed bank of the study area is represented by 94 species belonging to 71 genera, distributed in 29 botanical families. The seed bank of the four study areas consists predominantly of species of herbaceous habit and floristic composition varies according to the stage of natural regeneration, being higher in more advanced stages. [ABSTRACT FROM AUTHOR]