Banco de sementes do solo em ecossistema sucessional na Amazônia Oriental, Brasil.

Abstract

The seed bank is an important indicator for the evaluation of restored areas. It’s a response to the dynamic succession process, representing part of the potential stock of stakeholders within the ecosystem. Thus, the objective of the present study, was to evaluate forest structure and composition of the seed bank in a successional area 32 years after multiple cycles with plots subjected to different treatments. The 120 samples distributed in three treatments, were obtained with sampler in square format with an area of 0.0625m² in the evaluation period of eight months. A total of 1810 seeds were identified, distributed in 32 species and 26 families with a total density of 692 ind./m². The speeds and the mean time of emergencies of the treatments varied from 2.5 to 6.13 seeds emerged per day, and on mean from 60 to 54 days. The density and number of emerged seeds the highest occurred in the Control, followed by the Irrigation treatment and the lowest value for the Removal treatment, with significant differences (p <0.01) for the density variable. The estimated degree of equability (J ') closest to one was that of the Controls plots (0.78) which differed significantly from the other parcel (p <0.05). And Shannon the values indicated better seed bank homogeneity in the plots of Removal that presented lower value (p <0.05). Which means that few species at the collection site are responsible for the highest proportion of seeds in the soil. The species present in the seed bank were classified according to dispersion; habit of life and; ecological group. They stood out zoochoric dispersion; shrub form; and pioneer individuals respectively. This study provides important information that characterizes the seed bank in forest ecosystems regeneration process, indicating that pioneer tree and shrub individuals are responsible for the post-disturbance process.