Banco de sementes do solo de sítios de Caatinga sob influência do Projeto de Integração do Rio São Francisco

Abstract

The study of the seed bank (SB) can be used as an important tool to ponder the conservation status of plant species and their environments. Thus, this study aimed to evaluate the SB Caatinga sites under the influence of the works of the São Francisco River Integration Project with the Watershed of North Northeast (PWNN). The study area located in Sertânia, PE, was divided into three environment: Environment 1 – Caatinga site changed by the works of PWNN; Environment 2 – edge of the Caatinga fragment; Environment 3 – Inside Caatinga fragment. The collection of soil was made in sample units of 20 x 20 cm, totaling 20 samples per environment. The evaluation of the seed bank was performed by emergency method of seedlings. In all, registered 63 species, 17 in Environment 1, 43 in Environment 2 and 44 in Environment 3. Inequalities between environments observed in this study appear to be a direct reflection of existing biophysical differences between the sites. It is concluded that the SB of the studied sites show significant differences among themselves in the abundance and diversity of species, especially given the large number of propagules of invasive alien species.